May 2012 Cover Page


   
May 2012
  
The Rifleman's Journal
A Collection of Articles Dealing with Rifle Accuracy Topics


This Month:
Hap Rocketto - Hap's Corner
Germán Salazar - Lapua Rimfire Service Center
Germán Salazar - Nammo Tactical Ammunition .338LM
Germán Salazar - Accuracy Secrets of the .30-06



15 Cents 


Cartridges: Accuracy Secrets of the .30-06 - Part 3


Accuracy Secrets of the .30-06 - Part 3
by Germán A. Salazar

Having discussed barrel and chamber reamer choices in Part 1 and a few specific accuracy loads in Part 2, we now move into the final installment of this short series and we'll discuss some reloading tools and techniques for accurate loading of the .30-06. Obviously, good reloading practices are applicable to any cartridge and it isn't my intention to make this an article on how to reload; the purpose of this is to highlight things that are either unique to the .30-06 or of particular importance on the .30-06. I will assume that the reader has a solid knowledge of reloading generally and accuracy reloading specifically, and accordingly, will skip or gloss over many of the basic items that are common to all cartridges.

Brass
One of the great virtues of the .30-06 is the huge variety of brass available for it. One of the real curses of the .30-06 is the huge variety of brass available for it! Huh? Well, it's kind of fun to see all the different headstamps and to try new types of brass, but it can absolutely drive you mad trying to maintain a consistent level of performance. I have .30-06 cases that weigh 176 gr. and I have others that weigh over 200 gr. - and plenty that are in between. Clearly, the load has to be adjusted as you switch from one type of brass to another. Then there's neck thickness; it varies as much as case weight and can also cause problems.
1. Brand Selection. The first recommendation regarding brass is to standardize on one brand, or at most two brands, of brass. There will still be some lot to lot variance, but it won't be too much. If I were going to the store tomorrow to buy all new .30-06 brass, it would be Lapua or Norma if the budget allowed it and Winchester as a great alternative. Those choices are based on my observations of brass quality as discussed in item 3 below. However, if you love another brand, or have it already, that's fine and you'll develop your loads around that type.

2. Neck Turning. Because of all the variability in brass, I turn all case necks to the same dimension: 0.0125" thickness. That means I take a lot off of a Lapua case and a little off of a Winchester and kind of in between for a Lake City. But, and this is the critical point, doing so allows me to use the same sizing die setup and obtain the same neck tension on the bullet with any brand of case. Click here for earlier neck turning article.



NECO Audette case tool
3. Case Indexing. The .30-06 case is fairly long, which means that it will more easily develop a thick side and a thin side during the drawing process by which the case is made. The more draws the manufacturer uses in forming the case from the brass cup, the more uniform it will be, but the higher the manufacturing cost will be. Any significant variance in case wall thickness will definitely cause a degradation of accuracy and will make it difficult to get a truly concentric alignment of case and bullet because the case will quickly develop a banana shape. I use the NECO made version of the Creighton Audette tool to check the cases, mark them on the thin side and then insert them into the chamber with the index mark always in the same orientation. Since I began doing this with the .30-06, I've seen a distinct increase in my X count and maybe a couple of points in the aggregate. The effect was not as noticeable with short cases like the 6BR which aren't stretched as much during manufacturing and thus maintain more even wall thickness. To learn more about the process, read this earlier article.
I think if you do those three things, you've addressed the main concerns with .30-06 brass. Any other form of brass sorting or preparation that you believe to be worthwhile is fine, although I've never been one to weight-sort brass or deburr flash holes. If it makes you feel good, do it, if it doesn't, that's OK as long as you took care of the three big items.

Resizing
1. Sizing Die. I have six or seven .30-06 sizing dies including bushing dies, body dies, neck dies, and conventional full-length dies. However, almost 100% of the time, I use a standard Redding full-length sizing die that I bought used for $5 from a fellow shooter at the range; I even got a seater for that price. Why? Simply because it is a great match for my chamber. Once I saw how well it sized, I adjusted my neck turning dimension so that this die would give me the neck tension I want without oversizing. When you can just barely feel the expander ball gliding over the inside of the case neck, you've got it right.
The great body fit with the standard Redding die is nice, but the Redding bushing dies also have a great body fit and you can adjust the neck to any tension, right? Yes, but there's one more reason to use a standard die over a bushing die: concentricity. A once-piece die that doesn't overwork the neck will almost always give you better concentricity than a bushing die because the bushing has to have some radial clearance for ease of insertion and that thousandth or two of clearance will degrade concentricity. Allowing the bushing to float a tiny bit by not clamping the top down tightly (just back it off a tiny little bit) helps, but a one-piece die is still better.


2. Headspace. The longer a case is, and the more tapered it is, the more it will grow each time you resize it; and the more it grows, the sooner you will run into a case head separation. With modern case designs such as the .308 or the 6BR both of which have moderately sharp shoulder angles and straight bodies, you need to set the shoulder back 0.002" or so in order to ensure easy bolt operation and to avoid galling the locking lugs and seats. The .30-06, however, with its mild shoulder angle of 17.5 degrees and it's long, tapered body, works just fine with a 0.000" setback. This isn't the same as neck sizing, because you're still sizing the whole body. However, if you work carefully, you can set your die for 0.000" to 0.001" setback, extend case life a little (I get 11 to 13 firings from most of my brass) and maintain reliable functioning.








Tooling
We've covered all of the basics and there isn't really any tool that's unique to the .30-06, but some take on extra importance with this cartridge.

Forster Headspace Gauge
A good headspace gauge that you can use quickly and easily is essential. I have two that I rely on: a Mo's thimble type gauge ((203) 775-1013) and a Forster case gauge (the Wilson is virtually identical). They do the same thing: give me a shoulder setback reading and allow me to check trim length.













Mo's Headspace Gauge























The NECO Audette tool is critical to me. Without it, I know that my scores would be a little lower and I don't have any room to give up points or X's. I get a lot of peace of mind from checking and indexing my brass with the NECO tool.

Giraud Case Trimmer






















The case trimmer is another big item. With a 6BR you might trim every seven or eight firings because that short, straight case seems to never grow - that isn't so with a .30-06! I use a Giraud case trimmer and trim the cases on every firing. These cases grow quite a bit and I don't take any chances with safety. A manual trimmer takes a long time and I would be tempted to skip this step now and then without the Giraud, so this is a convenience item, but really a safety item.


Conclusion
Our objective is to create ammunition capable of consistent high scores at distances from 300 to 1000 yards under match conditions. That means it might be 40 degrees, or 110 degrees; it might be a calm day or a windy day, it might be raining, it might be blowing dust - in any of these conditions, if the ammunition causes rifle functioning problems, the match is already lost. Careful attention to the tips in this series should allow you to load .30-06 ammunition fully capable of winning matches at any distance against competitors of skill similar to your own.


Cartridges: .30 Caliber Magnum Improved AMU

This month we have a letter from our old friend Dan who inquires about a little known cartridge. We've asked Ray Meketa, who has an encyclopedic knowledge of target cartridges to illuminate the darkness for us and, notwithstanding his characteristic modesty, he came through with a lot of information. - GAS -

Cartridges: .30 Caliber Magnum Improved AMU
by Ray Meketa

Germán, Dan again. I was hoping that you might be able to add to my collection of out-dated and archaic knowledge of Long-Range cartridge development. I recently ran across a can of .30 AMU-Improved Brass that is in white paper boxes. The internet is not exactly full of information. Is there any articles that cover the genisis of the .30 magnums as a Long-Range cartridge? Where would I find a good resource to track the development of .30 magnums from 300 H&H in the 1930's to their peak before the current sub-caliber craze; and maybe even their recent re-emergence in F-Class (at least in the 7mm variety)?


.300 Magnum Improved-AMU two different headstamps

I have 5 boxes of "Improved AMU" brass. The bullet type listed is "200 GRAIN T.H. MATCH" and the ink-stamped lot number is "RA-5003". I have also observed that one of the boxes of casings bears the R-P headstamp, and not the REM-UMC headstamp. As a footnote, I think that the past owner canabilized the powder and bullets for his own personal use in another big 300, or possibly the AMU itself.

Dan


 

*********************************************************


Dan,
All that I know about the big magnums is mostly common knowledge.  I have a very few in my collection that I can show you but that is it.  Anyone interested in the AMU aspect should contact some of the old timers who were directly involved back in the early days.  From a competition standpoint, someone like Randolph Constantine can cite chapter and verse.  I believe Randolph wrote an article for COTW (Cartridges Of The World) back around the turn of the century that covered the long-range cartridges.

Anyway, everyone knows the story of Ben Comfort and the 1935 Wimbledon that kicked off the .300 Magnum craze.  World War II soon put a virtual halt to most competition but it wasn't long after the war that things picked up where they left off.  In 1947, Frankford Arsenal reported that a small quantity of .300 H&H cartridges were manufactured for the USMC for International competition, but not much is known about them.  They supposedly had a Winchester 180 gr. bullet, loaded with HiVel #2 to 2825 fps.  It's not even clear if they were loaded by Frankford or by Winchester.  Since there are several known boxes of Winchester 300 H&H Match ammunition from that time period, my guess is that it was W-W and not FA that loaded it.


.300 Ackley Magnum WCC 60

When Army Marksmanship Unit (AMU) was established in 1956, much of their early ammunition was loaded by W-W and Remington but they also did a lot of handloading on their own using components purchased or, in some cases, bullets that they made themselves.  I have a carton of .300 Ackley Magnum loaded by W-W that has a WCC 60 headstamp.  








.300 H&H Magnum (left) .300 Magnum Improved-AMU (right)
A later loading by RA (Remington Arms)  was called the .300 MAGNUM IMPROVED-AMU.  It wasn't a lot different than the W-W .300 Ackley Magnum.  Remington used a bunter that had the H&H ground off, giving the brass a unique headstamp. 



The R-P headstamp you mentioned would date the brass after 1960.  The 200 gr. boattail bullet is probably the same one that they used for the 7.62mm NATO Match ammunition for the AMU.  I've never chronographed the 7.62mm cartridges but I'd guess they are low velocity for International or Olympic shooting.

Later still, most of the magnum ammunition consisted of the plain vanilla .300 Winchester Magnum specially loaded with match type bullets.  One recent loading is the Mk 248 loaded with the 220 gr. Sierra Match King at 2850 fps - a pretty hot load.
And that's pretty much all that I know.  Here's a few photos from my files showing the cartridges that I have.


Ray



Remington 7.62 Match - headstamp is RA (+) 59. Bullet was an FMJ Boat Tail 200 gr.


Western .308 Match - headstamp is WCC 60. Note blunt shape and long bearing surface of the 197 gr. bullet.





Cartridges: Accuracy Secrets of the .30-06 - Part 2

Accuracy Secrets of the .30-06 - Part 2
by Germán A. Salazar

In Part 1 of this series we discussed the foundation of an accurate .30-06; that is selecting the right barrel blank and chambering it for best accuracy. In Part 2 we'll detail some specific match proven loads for the only cartridge you really need.

The truest "secret" of great accuracy in the .30-06 is to keep the load close to, but under SAAMI's maximum pressure standard. The loads I've set out for you in this article do just that. As a result, they are accurate, safe, and won't put undue wear on your action or barrel. The .30-06 has plenty of case capacity and will give very good muzzle velocity without exceeding safe pressures. Remember, it isn't a magnum; but it's a lot better than a .308. If you can live in that happy medium ground of .30 caliber ballistic performance, then you'll get a lot of satisfaction from the .30-06.

There are three loads that I shoot regularly in the .30-06 with readily available components. I don't really spend a lot of time working with new powders or bullets because for NRA Highpower Prone shooting, these loads do just about everything I want. I am, however, working on one new load and I'll tell you about that as well; so you'll get three proven loads and one experiment.

I've covered some of these loads previously in our .30-06 Update article, but there are a few refinements, a few more details, and another year of shooting them has shown that they're still good loads. In each case, I'll give you the exact components I use and some acceptable substitutes where applicable.



The Mild Mid-Range Load
One of the fun things about the .30-06 is that you can load it down quite a bit and still retain all of its inherent accuracy. In fact, that's nothing new, as the Frankford Arsenal and Lake City Match and National Match ammo were loaded like this in order to function properly in the M1 Garand without damaging the Garand's somewhat delicate op-rod. This load is really just a duplicate of those old match loads and is extremely accurate. It shouldn't be thought of as a reduced load because the arsenals cranked out millions of rounds just like this and it is a full pressure load, but it's pretty mild in recoil. This is the only load in this article that is suitable for the M1 Garand, or the 1903 Springfield type rifles.

Brass: Lapua (Lake City or Winchester are acceptable substitutes)
Primer: Federal 210M (PMC, CCI BR2 or Winchester WLR are acceptable substitutes)
Powder: H4895, 47.0 gr. (IMR 4895 and IMR 4064 are acceptable substitutes with minor charge adjustment)
Bullet: Sierra 168 gr. Match King moly (all Sierra or Berger 155 gr. are acceptable substitutes) cut the powder charge 1.0 gr. for bare bullets. Seat the bullet for 0.020" jump to the lands.
Muzzle Velocity: Approximately 2720 fps from a 28" barrel.

This load is extremely accurate despite having a lot of air space in the case and the bullet jump which I normally avoid in my loads. You'll feel slightly less recoil that with a typical .308 Palma load, but don't raise that powder charge; these are fast burning powders and although mild in recoil, you're close to maximum pressure.



The All Purpose Load
On any given weekend here in Phoenix, we might have a match at 300, 500, 600 or 1000 yards. Sometimes I get a bit caught up with daily life and reloading for Saturday gets neglected; that's when this all-purpose load saves the day. I always have a full box (72 rounds) of this on hand and it has allowed me to shoot a match rather than stay home more than once. Of course, if the load weren't accurate at each of those distances, I might as well stay home. Thankfully, it is very accurate and the best example of the .30-06's all-purpose nature that I can think of.


Brass: Lapua (Norma or Winchester are acceptable substitutes)
Primer: PMC (Russian) (F210M or CCI BR2 are acceptable substitutes)
Powder: H4350, 53.5 gr.
Bullet: Sierra 190 gr. Match King moly (Berger 190 gr. VLD is an acceptable substitute) cut the powder charge 1.0 gr. for bare bullets. Seat either bullet for 0.020" jam into the lands.
Muzzle Velocity: 2800 fps from a 28" barrel.

This load is very close to maximum pressure with my lot of H4350 and you should absolutely work up to it because your lot won't be the same; even a change of primers can add 3,000 psi instantly. That goes double if you're using bare bullets because although the indicated 1.0 gr. reduction is a good rule of thumb, being careful and really checking things out is the only prudent approach.



The Long-Range Load
I've been working on this load for some time and am satisfied that I've got just what I need now. This isn't exactly a set of commonly available components, but it isn't too exotic either. Basically, the load was a result of trying to work with H4831sc for long-range because I've always seen excellent accuracy from that powder. However, because of it's slow burn rate and low density, the case is full a few grains below what it takes to match the muzzle velocity from H4350. That kept me from trying it at long-range for a while. However, when I brought the super thin Norma brass and the Cauterucio 200 gr. VLD into the picture, it came together perfectly and it's been very good at 1000 yards so far.

Brass: Norma 
Primer: PMC Russian (Federal 210M is an acceptable substitute)
Powder: H4831sc, 57.5 gr. 
Bullet: Cauterucio 200 gr. VLD moly (Berger 190 gr. VLD and Sierra 200 gr. Match King are acceptable substitutes). Seat all bullets for 0.020" jam into the lands.
Muzzle Velocity: 2675 fps estimated from a 28" barrel. I haven't chronographed this load, the MV is based on other loads with the same powder. It's a reasonable estimate, but I'll update this when I get a chance to chronograph the actual load.

This load cannot be safely used with other brass. Norma is much lighter than any other brand and allows the safe use of this load. I've shot a few 1000 yard matches with this load and the scores have been in the mid to high 190's with a high stage score of 199-10X. All matches were shot with iron sights from the CSS tubegun with a Hart 1:11" twist barrel, PTG Serengeti chamber as described in Part 1 of this series.



The Experimental Long-Range Load
I really like my current long-range load, but I have a small supply of the 200 gr. VLD Cauterucio and I haven't tried getting any lately so I don't know how hard or easy it might be. In the meantime, I have a good supply of Berger 185 gr. BTLR and they are a great long-range bullet in my Palma and F-TR rifles, so I am confident that they'll also work great in the .30-06. I haven't done any testing at all with this yet, but I have a solid idea of which components I'll use. During the summer I'll do an initial work-up at 500 yards and then once we get back to 1000 yard shooting in the fall (or maybe in California during the summer) I'll report back on my results.

Brass: Lapua (Norma or Winchester are acceptable substitutes).
Primer: PMC Russian (Federal 210M is an acceptable substitute)
Powder: H4350, no charge weight at this time.
Bullet: Berger 185 gr. BTLR moly (Berger 185 gr. Hybrid is an acceptable alternative).
Muzzle Velocity: unknown at this time




Coming Next
In Part 3 we'll discuss some tools and techniques that I use to maximize accuracy when loading the .30-06 for competition.



Cartridges: Accuracy Secrets of the .30-06 - Part 1

Accuracy Secrets of the .30-06 - Part 1
by Germán A. Salazar

"The .30-06 just can't beat a .308."
"The .30-06 recoils too much."
"The .30-06 case is too long for real accuracy."
"Everyone knows the military switched from .30-06 to .308 because the .308 is more accurate."
"Snipers use a .308, not a .30-06, that should tell you something."
"The .30-06 is old, out of date, an antique - you can't win matches with it."

I love  hearing statements like those, it lets me know that whoever is uttering them is going to be easy pickings in a match because he underestimates the competition and won't be working as hard as he should. The .30-06 vs. .308 debate has been going on since the day the .308 was introduced to the public and probably won't die anytime soon. We've covered the .30-06 vs. .308 debate before (click here for article) with extensive data from over 6,000 rounds fired in actual rifle matches, not keyboard pounding, so we won't do that again. What we're going to discuss is how to put together a .30-06 for NRA prone, F-Class, tactical or other recreational matches that will be competitive, reliable, long-lasting and moderate in cost.

Amazingly, the .30-06, a cartridge with well over a century of unmitigated success on the range and in the field is rarely seen on the Highpower range these days and is poorly understood by a generation of shooters raised on plastic rifles firing cartridges nearly suitable for rodent control. The .30-06 conquered the 1000 yard ranges from Camp Perry to Quantico, from Camp Pendleton to Fort Benning and all points in between - not to mention the battlefields of Europe in two World Wars where the average firing distance was long and the stakes immeasurable. Yes, history matters, in real life as well as in competitive shooting and the .30-06 is most certainly not a dusty relic of history; it is an accurate, powerful cartridge, capable of exceeding it's many offspring in any measure of ballistic performance. Beating the baby cartridges with the .30-06 doesn't take any voodoo or exotic components, just attention to details and the careful application of a century of accumulated wisdom.

Barrels
There's no getting around this basic fact: you need a top quality barrel to get top quality accuracy. The barrel is the heart of the system and no mass-produced barrel is going to perform on a par with a Krieger, Bartlein, Hart, or other performance barrels made specifically for accuracy. If you're working with a factory or arsenal barrel, the end results will be somewhat limited, but you can still outshoot the ,308 and others with similar factory barrels; we'll cover that in a bit more detail further on, for now, let's look at new barrels.

Makers - I use barrels from Krieger, Bartlein and Hart in my rifles with no particular preference, although I find Kriegers usually easier to get as Bruno's keeps the profiles I like in stock (he has Hart and Shilen also). Krieger and Bartlein are made by the cut-rifling process whereas Hart barrels are button-rifled. I have a slight preference for the cut-rifled barrels because I believe the process is more likely to result in perfectly consistent twist rate, but my two main .30-06 rifles have Hart barrels, so this really isn't a big issue. The four items in barrel choice that genuinely matter are internal dimensions, rate of twist, length and weight; let's take a look at each.

Bore & Groove - Although it would barely seem to be worth mentioning, the bore and groove dimensions should be 0.300" x 0.308". Krieger, Bartlein and perhaps other makers offer barrels with slightly smaller internal dimensions, these are intended for chambering in .308 for international Palma shooting where issued ammunition often has bullets slightly smaller than .308" diameter. This is not a concern for the US shooter using match grade bullets and in any event not an issue at all for the .30-06. More importantly, those reduced dimensions may cause excessive pressure with some of the long, heavy bullets we prefer for the .30-06. Stick to the standard 0.300" x 0.308" dimension for your .30-06, that's what it takes.

Twist Rate - The standard rate of twist for factory and arsenal barrels chambered in .30-06 is 1:10". This was established in 1903 with the .30-03 cartridge that used the Krag's 220 gr. round-nose bullet at a very modest muzzle velocity. As the cartridge evolved into the .30-06 with a 150 gr. spitzer bullet, the original rifles had their barrels set back and  rechambered with the new short-throat chamber for the lighter bullet, but naturally the rate of twist remained the same. That's ancient history and we don't need to repeat it; what we need is the optimal rate of twist for modern match bullets, and that is the 1:11" twist.  This will properly stabilize bullets up to 210 gr. with no concerns and that's as heavy as we're going to consider in this series.

As a fundamental rule, the slower you spin a bullet the more accurate it can be. The reason is simply that bullet jackets aren't perfectly uniform in thickness and a slower rate of spin keeps those tiny variances from altering the bullet's flight. Think of a car tire with a slight imbalance, the faster you go, the more you feel that thumping. The bullet is the same except that because it isn't held by an axle like the tire is, the imbalance will make it wander slightly from its original path. The limitation we face on rate of twist, is that although we want it to be slow for accuracy, we need a certain amount of twist for stability. The 1:11" twist will stabilize all useful match bullets, whereas a 1:12" twist is marginal with some 190 gr. bullets and all of those that are heavier. Accordingly, we can rule out the 1:10" twist as unnecessarily fast, the 1:12" as potentially too slow, and settle on the 1:11" as being just right. Accuracy won't necessarily suffer much with a 1:10", so if you have one, that's fine, if a touch less than optimal. I would avoid the 1:12", however, because it will limit your bullet choices.

Length & Contour - Long and heavy is the rule of thumb for a .30-06 barrel. Let's start with length; I consider 28" to be the ideal length for a 30-06 barrel. This is long enough to take full advantage of the powder charge you're burning. Although a 30" barrel will give slightly higher muzzle velocity (about 25 fps) given the heavy contours that are called for, I prefer to keep the length at 28" to reduce fatigue during a string. If you're shooting F-Class or another form of supported shooting, then a 30" barrel can be worth considering, but nothing longer than that for reasons we'll discuss in a Part 2.

There is no reason to use a short (under 28") barrel on a .30-06 when you have the choice; of course, if you're working with an existing barrel that's a different matter, but you won't get quite the performance level of the right-size barrel. When you burn 53 to 60 grains of relatively slow burning powder, you generate a lot of hot gas ready, willing, and able to push the bullet to a high muzzle velocity, you need to give it room to work and that's what happens as the gas pushes the bullet up the length of the barrel. A .30-06 would see increasing muzzle velocity from a barrel as long as 45"; while that's not practical for a host of reasons, don't cheat yourself of a real ballistic advantage by cutting the barrel off too short - they don't grow back.

When picking a barrel contour, weight is your friend. Yes, the .30-06 generates more recoil than a .308, that's just basic physics; shoot the same bullet at a higher MV with more powder and you get more recoil. If you shoot a heavier bullet, as you should, then you get even more recoil. Now, this additional recoil isn't objectionable, even a tired old desk jockey with a bum shoulder (yours truly) can handle it, but a heavy barrel is one of the ways to make it reasonably comfortable. Normally I use the MTU/AMU profile that all the makers offer (Krieger #9), although I have a couple of heavy Palma barrels (Krieger #14) that work out well also - 6.5 lb. of barrel weight is your friend.

Chambering
You might think that after 106 years there wouldn't be much to say about chambering a .30-06; actually, that's not entirely true, there are some fine points to consider. The first question to ask your gunsmith is whether he has a print for his .30-06 reamer; you really don't want to build a match rifle around an old  hunting style .30-06 chamber of unknown dimensions. Even a lot of the old "match .30-06" reamers aren't a good idea because many of them had a 3 degree leade angle which will hurt accuracy compared to the 1.5 degree leade angle used today. Your best bet is definitely to buy a reamer for your project and take good care of it. If you think that 200 gr. is the heaviest bullet you're likely to shoot on a regular basis, then the Pacific Tool & Gauge Serengeti reamer, print no. 9685 is really a great choice. PTG makes great reamers, and this design works very well with bullets from 155 gr. to 200 gr. thanks to the freebore length as well as the case's long neck that gives a lot of flexibility in bullet seating depth. It is also a very good match to Redding sizing dies, another a worthwhile consideration.

If your preference is for heavier bullets like the 210 gr. and 215 gr. models now offered by Berger and Sierra, then I would suggest asking PTG for 0.070" longer freebore. That will still allow you to use medium weight bullets as well as the heavier ones. At this point, you might as well get a 1:10" twist barrel just for a slight margin of safety with respect to bullet stability in cold temperatures. I think once you go past the 200 gr. bullets, you're out of the "normal zone" with the .30-06 and it becomes a specialized chambering as opposed to an "all-around" shooter which is the .30-06's great strength.

If you want to shoot 230 gr. or 240 gr. bullets, the best bet is to throat the barrel after chambering to place those bullets exactly where you want them in the case neck. That's a more specialized operation, of course, but you'll really be building a single bullet rifle with a very fast twist rate that's beyond our discussion today.

Neck diameter is standardized at 0.340" for the .30-06 and it's a good dimension for an accuracy rifle. Although I turn my case necks to 0.0125" thick, for a loaded round neck diameter of 0.333", I don't consider that to be excessive clearance. Due to their length and taper, .30-06 cases will only last about 11 full-length sizings before you begin to see signs of head separation; therefore, I'm not worried about the 0.007" neck clearance accelerating case neck cracking (which would take at least 20 loadings), and it doesn't hurt accuracy. If you're sure you'll be turning necks, you can go smaller; but consider that unturned Lapua brass will yield a loaded round with a  neck diameter between 0.337" and 0.338". That's as tight a clearance as I'm comfortable seeing on unturned brass; the 0.340" chamber neck is an all-around good choice.

Coming Next
In Part 2 we'll discuss brass, bullets and powder for .30-06 match loads. If there's room we'll talk about some tools and tidbits, if not then there will be a Part 3.


Pacific Tool & Gauge .30-06 Serengeti Reamer



Good Stuff: Lipski Rear Sight Base

Good Stuff: Lipski Rear Sight Base
by Germán A. Salazar


"How do I mount the rear sight on a spacegun or tubegun?" That's one of the most frequent questions I get from new shooters building a rifle for NRA Highpower shooting. The simple answer is that you use a Lipski base. Al Lipski has been making these for a long time (he makes other goodies too) and they simply work. The Lipski base is as rugged as an anvil and not much more complex, that's what I like in Highpower equipment - rugged durability and clean design.

Obviously, the problem to overcome in mounting a rear sight on a spacegun or tubegun compared to a conventional bolt-action rifle is that you can't just bolt a side plate to the action because the receiver is too big in diameter and in any event, the sight needs to be much higher than the receiver due to the high comb  position. However, you have that nice looking scope rail sitting there just begging to be used since I know you aren't even thinking about using a scope - right?

Al's base clamps right to the rail with a good old American 1/2" hex nut. You won't be fishing around your toolbox for Torx or Allen or metric components, this is blacksmith solid, but made with a high level of precision on modern machinery. Snug it up tight, but don't act as though you're torquing lug nuts on your truck!








Once you clamp the sight base to the rail you just mount the sight to it. You can make coarse elevation adjustments on the base itself to line up the front and rear sights properly or to set up the rear sight to your preferred head position (high or low) by screwing the side plate to the base portion in any of the three height settings provided. Use Loctite Blue on the screws when you find the final setting.

OK, you need an Allen wrench for this, but it's in inch sizes! Believe me, Al is not a guy to go for exotic stuff, simple rugged and well crafted is his style. Did I mention he's an acclaimed chainsaw tree trunk sculptor? You get the idea...



I have five Lipski bases in use on everything from 6BR, .308 and .30-06 and have never had on come loose or give me any sort of trouble. I noticed on a recent picture of Carl Bernosky at Camp Perry that he uses the Lipski base on his spacegun - good stuff.








You can order the Lipski base from Brownells.com, White Oak Precision, OK Weber, Creedmoor Sports and Fulton Armory.

When you order you'll see that there is a "Weaver" model and an "AR15" model, they are the same unit, the side plate just comes assembled in different directions on them, so get either one, you'll be moving the side plate around anyway.





Hap's Corner: Ammunition Is Not a Matter of Life and Death...


Ammunition Is Not a Matter of Life and Death…
by Hap Rocketto

There is an old saying among smallbore shooters that there are two things that are not long for this world: dogs who chase cars and smallbore shooters who can’t get hold of a good lot of ammunition. Such is not the case for the highpower shooter.  The fodder that is fed into the chamber of the rifle is the main difference between smallbore and centerfire, a situation that might be best illustrated by having both shooters head to Camp Perry by air and along the way have their shooting kit disappear, without a trace, into the friendly skies, a not unlikely occurrence.

Full of disappointment, but with Commercial Row and unlimited funds at their disposal, each can re-equip himself with the best of everything from the ground up, shooting mat to rifle to shooting hat.  More importantly, the high power shooter can buy a reloading press, dies, scale, and components to manufacture a cartridge that will shoot just as well as the ammunition that went missing.  Right out of the reloading manual he can pick a number of loads that have been tried and proved true.  The old standby .308/7.62mm load of a 168 grain hollow point boat tailed bullet ahead of 41.5 grains of IMR 4895 powder comes immediately to mind. 

The smallbore rifleman, on the other hand, can buy the finest, most expensive, rimfire ammunition on the shelf and not be sure of its performance.  Such is the fickle nature of the ammunition/barrel relationship for the smallbore community.  Smallbore rifles are sensitive to ammunition.  One man’s knot lot is barely fit to pot rats at the dump to another.  It is not uncommon to hear that some prone shooters budget as much as $1,000 per year for just the test lots that they use in their nearly Obsessive Compulsive Disorder ammunition testing methodology. To a rimfire rifleman ammunition is not a matter of life or death, it is far more important; as illustrated by this little anecdote.

A prone smallbore shooter of independent means and questionable character had led a hedonistic life composed mainly of drinking, gambling, smoking, chasing women, and shooting, not necessarily in that order. At long last his dissolute ways caught up with him and in his last conscious moments he wondered what awaited him in the hereafter, not a pleasant thought when he considered his misspent days.

When he at last arrived at his final destination he was quite surprised to find that his particular corner of eternity contained a billiard-table-flat, well manicured and lush, greensward of a rifle range.  The skies were blue, the breezes gentle, and the firing line covered.  There was a match every day, no entry fees, and a rich prize schedule.  He found ample parking behind his assigned firing point next to the club house with its five star restaurant.  Shops maintained by several well respected shooting supply houses occupied a street behind the statistical office.  Just outside of the gate of the range was a well landscaped shooters’ subdivision of very fine homes each with pool, patio, and a two car garage occupied by a sports car and a SUV suitable for the paraphernalia required of the shooting sports.

He took all of this in with a smug satisfaction of entitlement secure in the belief that he had beaten the odds and arrived in Heaven.  After a gourmet meal in the club house dining room he sauntered into the first shop, cognac snifter in one hand and a hand rolled Cuban cigar with an inch of ash in the other.  He was delighted, as would any parsimonious belly shooter be, to see a posted sign which read, “Help Yourself!  All Equipment is Free!” 

“I guess my licentious life style managed to slip under the radar” he thought to himself with undue pleasure.  He then went about selecting a fine European target rifle with sights and a scope, a new mat, was measured for a shooting coat and custom ear plugs, grabbed an equipment bag and filled it with a sling, glove, hat, shooting sweater, windmill, loading block, scope and stand, timer, some small hand tools, and a few other items of interest.

With his swag in hand he made his way out to the firing line.  Spreading out his new mat, he set up the scope, arranged the loading block and timer, slipped on his new  sweater, donned his shooting coat, adjusted the sling, snapped it to the fore end block, squiggled into position and dry fired a few shots at the target hung down range.  Satisfied with everything he lifted the top of the loading block.  His hand recoiled from picking up a round when he noticed an unknown headstamp.  Cautiously plucking the cartridge from the block to examine it he found, much to his disgust, that it was a high velocity 22 caliber Long with a 36 grain hollow point copper washed bullet.

With an exasperated sigh, things had been so prefect up to this moment; he undid his gear and got up to head back to the club house for some selected lots of his favorite ammunition.  Turning away from the firing line he noticed, for the first time, a smiling man dressed all in red leaning on a pitchfork by the range tower.

“Don’t mind me,” called over the man in red, his grin growing both wicked and wider, “And don’t bother going back for different ammunition, all we have is what is in your loading block.  We get it in bulk and it is always the same lot. I guess that is the hell of it.”

For the smallbore shooter, success is often in the minute details of ammunition selection and we all know that the Devil is in the details.  As the man in red said, “That is the Hell of it.”

Cartridges: .338 Lapua Magnum - Loading and Testing

.338 Lapua Magnum - Loading and Testing at Nammo Tactical Ammunition
by Germán A. Salazar

Bruce Webb, Vice-President, Nammo Tactical Ammunition
Everything about the .338 Lapua Magnum is big when you compare it to a normal cartridge like the .308 or the .30-06. In fact, the .338 LM is positively gigantic if you compare it to today's popular cartridges like the .223 and the 6BR. But as impressive as the enormous cartridge might be, I was even more impressed by the enormity of the effort expended by Lapua and its sibling company Nammo Tactical Ammunition to make the most perfect .338 LM ammunition possible for their various government clients. 

Our hosts at Nammo were: Pete Sioma, President of Nammo, Inc.; Scott Selle, President of Nammo Talley; and Bruce Webb, Vice-President of Nammo Tactical Ammunition who gave us a very complete tour of the .338 LM loading facility. We came away from our visit with a greater understanding and appreciation for the resources devoted by Nammo and Lapua to ensuring that their ammunition is a world leader in precision and performance. This isn't Lake City where billions of rounds of generic ball ammo spew from massive assembly lines each year; this is a medium scale, high-precision assembly plant for ammunition that will meet the expectations of the world's most demanding marksmen. 

Bruce Webb with priming machine
in background
As competitive target shooters, we are thankfully far removed from the world's hot spots where most of this ammunition is used and our loading efforts are focused solely on precision. However, a great deal of what we saw at the Nammo facility in Arizona is very much like the precision reloading we do for long-range competition, albeit on a larger scale and with a few high-tech twists that we'd all love to have as part of our loading capability.

The .338 LM brass and 250 gr. Lapua Scenar bullets are brought to the US from Lapua's manufacturing facilities in Finland while powder and primers are sourced in the US. All of the components come together at the Nammo plant in Arizona. Cases are primed in a purpose-built machine that seats the primer and checks optically to ensure that the primer is seated to the proper depth below the case head. Small batches of primed cases are then transferred from the priming area to the charging and seating area.

Primed cases are charged with powder and the bullet is seated, all on a fairly small machine by industrial standards. Although automated, the process is somewhat like a very large scale progressive loading press. Nammo prefers to keep many details of this part of the process from public view, so no photographs of the machinery were permitted. As each round comes off the loading machinery, it rolls past an inspector who checks for any visual defects and packs it into a custom-made 20 round box. These boxes are then packed into M2A1 ammo cans and pairs of cans are packed in a wooden crate for shipping. On the afternoon we visited, there were several pallets of crated ammo cans fresh from the machines and ready for shipment to the end user.

At regular intervals, finished rounds are pulled from the packing area for detailed inspection and testing. The first step of the process is pulling a few rounds apart for verification of the powder charge weight and primer seating depth. Following that procedure, a complete dimensional check of complete cartridges is performed by a General Inspection LaserLab scanner. This device is invaluable for not only verifying that the cartridges meet the specifications, but for creating the data file in an archivable format for future reference and comparison.

The LaserLab measures lengths, diameters, tapers, radii, headspace, mouth diameter, perpendicularity, straightness, concentricity, primer pocket diameter, extractor groove diameter and more. Nammo holds bullet to case concentricity levels to the same standards as quality handloads: under 0.003".  Just in case you're interested in one of these, we were told it costs somewhere in the range of US$ 50,000. As impressive as that was, it was the next phase of quality assurance that really captured my imagination.

Sample rounds are regularly taken to the on-site 300 meter test tunnel; a facility similar to the 100 meter tunnel at the Lapua Rimfire Service Center, but on a much larger scale. This facility is run by Lane Ponich an accuracy industry veteran who is familiar to many of our readers. Lane brings a great deal of loading and testing experience to the operation and the results show it.


The tunnel has equipment for pressure testing as well as accuracy testing with two machine rests mounted in parallel. Pressure testing is conducted using a piezoelectric transducer connected to an Oehler System 85. This is a more accurate and reliable system than consumer level systems that use a strain gauge on the barrel such as the Oehler System 43 that I use. Although the System 43 is perfectly adequate for hobby level reloading, commercial loading to certify compliance with SAAMI and CIP standards relies on the additional accuracy of direct measurement by the piezo method.

Temperature conditioning unit for test ammunition

The piezoelectric transducer measures pressure directly from the cartridge by way of a hole drilled in the case which is aligned with a hole in the chamber that vents into the collar holding the transducer. Prior to firing, the test cartridges are brought to the desired temperature in an on-site oven/freezer unit that can bring the ammunition to any desired test temperature. Although SAAMI pressure testing standards call for ammunition to be conditioned to a temperature between 60F and 80F, Nammo tactical ammunition is additionally tested between -40F to +140F (-40C to 60C) to ensure safety and performance under the extreme conditions that the end-user may encounter.


Once pressure testing is completed, accuracy testing begins. The Oehler System 85 has electronic targeting capability, eliminating the need for optical aiming which can be difficult in any tunnel due to temperature variance within the tunnel and the resulting mirage. Although the exact accuracy standard to which the ammunition is held was not disclosed, we noted 300 meter test groups well under one minute of angle as the norm and none that exceeded that traditional measure of accuracy. In fact, a significant portion of the ammo lots being tested were coming in under 1/2 MOA. I found the level of accuracy being consistently generated from a cartridge with nearly 100 gr. of powder and a 250 gr. bullet to be very impressive - to say the least.

1000 meter penetration test on 2mm steel plate

Twin machine rests, accuracy (left) and pressure (right).
Note the overhead fans to regulate barrel temperature.
Rate of fire is carefully controlled and barrels are cleaned frequently.
If I had these resources at my disposal for testing my own handloads, I'd spend endless hours trying out different combinations in search of maximum precision. As we mentioned at the beginning of this article, we aren't very different from the Nammo staff and they're doing just that. It isn't the simple curiosity of the reloader that drives their efforts, however, it is the need to meet varying customer requirements.


Rifles chambered for .338 Lapua Magnum are not all alike; barrel contour, twist rate and length vary among makers and in some cases are custom ordered by the end user. In order to deliver the best possible ammunition to each customer, loads are adjusted to maximize precision and performance in the barrel type specified by the customer. Nammo maintains a large inventory of Sako actions fitted with test barrels matching each customer's requirements. Each type of barrel is duplicated, one for pressure testing and one for accuracy testing, and barrels are replaced regularly in order to maintain consistent data, unaffected by throat erosion. In this regard, the Nammo operation is more like a giant handloading shop than a typical arsenal loading operation.

I left the Nammo facility with a new appreciation for the capability of the .338 Lapua Magnum cartridge as well as the comforting feeling that those whose "target ranges" are somewhat more hazardous than those on which I spend my Saturdays are getting the very best ammunition possible. Nammo Tactical Ammunition might not be a household name in the reloading community, but it's one you should know.


Detail of pressure transducer mounted to barrel.
  

Did I forget to mention the .50 BMG? With Lapua ammo... Well, we have to leave something for another day...


McMillan .50 BMG action on test rifle.



 

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