History: National Match Ammunition

A Short History of National Match Rifle Ammunition
By Hap Rocketto

A rifle can be no more accurate than the ammunition with which it is loaded; therefore the search for the best ammunition is a life long pursuit for any shooter. Until recently serious service rifle shooters were more limited in choice because ammunition for the most important matches of the year, regional Excellence-In-Competition (EIC) Matches and the various team and individual matches that make up The National Matches, was issued on the line.

Any shooter who was seriously pursuing the Distinguished Rifleman Badge or Presidents Hundred Brassard would try to obtain and shoot as much of the government manufactured ammunition as possible to firm up zeros for 'Leg Day'. Until the advent of the 7.62mm M852 Match ammunition, which uses a 168 grain hollow point boat tailed bullet, the 173 grain solid point boat tailed bullets used in the 30 Caliber Match M72 and the 7.62mm M118 ammunition were hard to come by and this made handloading a National Match equivalent cartridge virtually impossible.

In 1975 the National Trophy Individual (NTI) Match at Perry cost just $7.00, and that also covered one night's lodging in a hut and three meals at the Mess Hall. The actual entry fee of the match was but $2.00 if you were not billeted on post. In 1990 the cost of the NTI was still low; only $9.00. By 1993, just three short years later, the NTI entry fee had risen almost 400% to $38.00. The rise reflected a charge for the 50 rounds of ammunition needed to fire the National Match Course. No longer a subsidized item, ammunition for the NTI costs now run $20.00 (40 cents per round) for 30 caliber and $25 (50 cents per round) for 7.62mm cartridges.

In 1995 changes in public law reorganized the National Board for the Promotion of Rifle Practice and the Office of the DCM. Now, no longer a part of the Department of The Army, but a public corporation, much like the Postal Service, the DCM has had to adjust. The change had its good and bad sides. On the positive side, the funding for the DCM is no longer a political football. However, the DCM has had to become a self-supporting agency and, to that end, prices for DCM services and commodities, such as ammunition, have risen accordingly.

Several factors have changed the complexion of the ammunition issue to some degree. The first is that the expense and difficulties involved in shipping ammunition to regional EIC matches caused the Director of Civilian Marksmanship (DCM) to modify match regulations to allow competitors to provided their own ammunition, either handloads, commercial loads, or National Match, at their own discretion. Secondly, the M-16, for which there is no National Match cartridge available, has become increasing popular in EIC competition because a rule revision that allows the M-16 shooter to 'roll their own' ammunition has made an accurate cartridge a reality. Finally, 7.62mm National Match M852 ammunition is now loaded with commercially available 168-grain hollow point boat tailed bullets. This makes it feasible to handload a cartridge that is both superior and cheaper than National Match ammunition. This chain of events makes it appear that National Match ammunition may become less important to a shooter chasing Distinguished in the future than it has been in the past.

Since 1907, when Section 4312 of Title 10 of The United States Code established the National Matches, there has been an ongoing search for quality service rifle ammunition. Frankford Arsenal produced the first National Match ammunition in 1908. The bullet was the 1906 uncannelured 150-grain flat-based spitzer. This bullet would be the standard for ammunition loaded through 1919.

Match ammunition for the National Matches was selected competitively from groups fired with samples sent to the government. Winchester Repeating Arms Corporation, United States Cartridge Corporation, and Frankford Arsenal were the suppliers during these years. The intent of the Army, through this process, was to both acquire an accurate cartridge while educating the manufacturers in the intricacies of mass production as they were taught how to navigate the government's paperwork labyrinth.

There were both intrinsic and economic reasons for the munitions manufacturers to attempt to vie for the contract. Along with the prestige of winning the competition for the most accurate ammunition went the award of a contract for several million rounds of ammunition. This insured continued employment for the workers and, in the case of the commercial firms, fatter dividend checks for the stockholders. During the early years there was no attempt to specially mark this ammunition. The best lot was designated for match use and shipped to the National Match site. The remaining ammunition was placed in the supply system for the use of troops in the field.

The method used to determine the quality of National Match ammunition is that of mean radius. Ten shot groups are fired from machine rested heavy barrels and the center of impact of the group is determined. From that point of reference the distance of each bullet hole is measured and then averaged. The resulting number bears no exact relationship to group diameter since that is a function of shape. However, a rule of thumb states that the group size at 600 yards will be slightly larger than the product of the mean radius and three.

For an example, in 1966 7.62mm samples had a mean radius of 1.76 inches indicating a group size of about six inches at 600 yards. This is just equal to the X ring on the present 600-yard MR target series and five inches smaller than the V ring on the old five-ring target. Each year, during the late fifties and sixties, service rifle shooters eagerly awaited The American Rifleman to read 'The Dope Bag' column containing the specifications of that year's National Match. Of great interest was the 270 round facsimile composite target that always accompanied the article and gave an excellent graphical portrayal of the ammunition's capability. In 1966 the facsimile target for the 7.62mm cartridge of lot LC12065 showed all 270 shots well within the ten ring with 242 of them in the X ring, which subtends just one minute of angle, bearing out the rule of thumb.

Changes to the ammunition began in 1919 when the Frankford Arsenal FA 70 priming compound was first used in the FA Number 26 primer. 1920 saw a change of bullet when a 170-grain flat based jacketed bullet was introduced in an attempt to reduce metal fouling the barrel of the rifle. This experimentation showed some promise so it was continued into the next year's production. This action resulted in the notorious 'Tin Can" bullet in 1921.

Townsend Whelen commanded the facility at Frankford and had developed a tinned cupro-nickel jacket that was thought to reduce metal fouling. Up to this time shooters were required to treat rifle barrels with a solution mixed from Ammonia Persulphate, Ammonia Carbonate, 28% Stronger Ammonia Water, and water. Officially it was Ordnance Department Metal Fouling Solution but more commonly it was known as "Ammonia Dope". Using it was a nasty and time consuming process that, when improperly done, would ruin a rifle barrel in just a few minutes. In an effort to reduce the metal fouling and avoid a disagreeable cleaning task, most shooters carried a small container of grease with which they coated the bullet prior to shooting. This was all well and good as the grease accomplished its purpose. For many years shooters in Great Britain have successfully used a parsimonious application of grease on the old .303 military cartridges to prevent metal fouling. Today that process has become so refined that some shooters, on both sides of the Atlantic, use just a carefully applied, prudently small, smudge of lubricant on the juncture of the neck and bullet.

Whelen's plated bullets and the cartridge cases were dissimilar metals. This resulted, over time, in the two components becoming cold soldered together. This binding increased the normal force needed to pull a bullet from 50 or 60, pounds to over 300 pounds, with some instances recorded as high as 600 pounds. Unless used sparingly and with care, the sticky grease could easily pick up debris and carry it into the rifle's chamber. Residue was inevitably left in the chamber and excessive grease build up may have been a contributing factor in causing the normal chamber pressure of about 51,000 pounds per square inch (PSI) to rise to alarming and dangerous levels of 75,000 PSI. With a clean chamber the neck of the case had enough room to expand and the bullet could be released. If the interior of the chamber were coated, and the diameter decreased, the space available for expansion was reduced allowing the pressure to build up to a level more than the rifle could handle. There are reports of bullets being found down range with parts of the neck of the case still attached.

Once the cold soldering problem was discovered warnings were published to advise competitors not to grease the bullets for fear of exacerbating the situation. However, these pleas fell on many deaf ears, probably caused by old habits and not the primitive ear protection of the day. Shooters who used the cartridges dry found that they were accurate and caused no damage. Some competitors that did not heed the warning, and used grease in excessive amounts or contaminated with grass or dirt, often found themselves with poor scores or, worse yet, an occasional wrecked rifle.

The possible danger of the high power community's use of incorrectly greased bullets caused the authorities to withdraw, and scrap, the remaining ammunition out of concern for the safety of the shooter. This was not the first time that greased bullets were considered dangerous and withdrawn from service. In 1857 Seypoy troops of the Old Indian Army mutinied when given bullets that they believed were lubricated with animal fat, the use of which would have caused them to break dietary laws or lose caste. Seventy-five years later the jury is still out as the controversy simmers about just what part, if any, grease may have played in the National Match ammunition woes of 1921.

In 1922 Frankford began loading ammunition with another new bullet. Continuing attempts to reduce metal fouling resulted in a 170 grain 6 degree boat tailed bullet that was jacketed with gilding metal to reduce metal fouling. Guilding metal is a hard alloy containing about 90% copper and 10% zinc. Its introduction solved both the metal fouling problem and served to help the boat tailed bullet maintain its stability in the bore. The switch to a boat tailed shaped projectile was a result of studies which indicated that the design was ballistically superior to a flat tailed bullet. The boat tail design allows the bullet to retain velocity longer, have less bullet drop, and deliver greater energy at long range than the flat based design. In addition the flat-based bullet required greater precision in manufacture to have a consistent concentric base-bearing surface. A concentric base-bearing surface is essential to stabilize a bullet. The boat-tailed design negated this manufacturing requirement while still providing the required concentricity. This attempt proved successful and has been continued in following years.

1924 would mark the last year that Hercules HiVel powder was used. Dupont's Improved Military Rifle (IMR) powders proved superior to the old standby and became the powder of choice. The bullet still was jacketed but the boat tail was changed to 9 degrees. The ammunition produced that year proved to be the most accurate of the .30-06 shipped by Frankford until 1962. The 1924 ammunition was also the first to bear the NM headstamp, FA NM-24.

The 1925 National Match ammunition was excellent. It marked the adoption of the M1 bullet, with a nominal weight of 172 grains and a 9-degree boat tailed shape, which is still used in M118 Special Ball. Dupont IMR 1147 powder filled the cases with the venerable FA Number 26 primer providing the spark to launch the bullet. There would be no matches held in 1926 as money was not appropriated and 1925 National Match ammunition would be used in 1927. In 1928 and 1929, ammunition would be produced, and be successful, in much the same manner.

In keeping with the concept that National Match production was to be a testing and development process for ammunition the 1930 production lot was used to test a new noncorrosive-priming compound. The insidious effects of the potassium chlorate in the reliable FA 70 priming compound meant that rifle barrels had to be scrubbed with boiling water after each shooting session or face almost immediate rusting. The staff at Frankford developed a noncorrosive primer that was to be field tested in 1931. However, in order to use it, the cartridge cases had to be Berdan primed, as opposed to the traditional boxer priming used with the FA 26 primer.

The two types of percussion primers, Boxer and Berdan, are very similar in concept but different in execution as both rely on the priming compound being placed between the firing pin and a metal anvil. When the firing pin strikes the metal shell of the primer, it pinches the priming compound between the shell and a metal anvil. The resulting friction detonates the highly volatile priming compound setting off the powder charge.

The Boxer primer, developed in the 1860s by Major Edward M. Boxer of the British Army, is manufactured as a separate unit and inserted into the cartridge case. It contains both a metal anvil and the priming compound that explodes and allows flame to pass through a single vent hole to the powder charge. This method is viewed as much safer and simpler because, as a separate component, it does not require excessive accuracy in manufacture, as does the Berdan primer.


The Berdan primer was developed in 1870 by Colonel Hiram Berdan, a United States Army Ordnance Officer. The primer that bears his name is an integral part of the cartridge case because a boss in the primer pocket of the case serves as the anvil. Two vent holes allow the flame to ignite the powder charge. Because the Berdan primer does not need an anvil it is capable of holding more priming compound that suited the needs of the new bulky noncorrosive compound.

For reasons unknown, the Berdan primer, developed in the United States, enjoyed a greater popularity in Europe and it is still used extensively there to this day while the British designed Boxer primer is the primer of choice in the United States.

The ammunition worked quite well and was even more accurate than the 1924 production run. It was subjected to a summer long test by the service teams and this proved to be fortunate. During summer training it was noticed that cases were showing evidence of excessive pressures and blown primers. The reason was believed to be the effect upon the priming compound of the unusually high temperatures at Camp Perry that year. As a result the ammunition was more carefully examined and then withdrawn from service. An alternate lot, prepared with the FA 26 primer and the headstamp FA 30, was quickly shipped to Camp Perry.

This unfortunate development delayed the general introduction a noncorrosive primer because there was hesitation to risk arming combat troops with a cartridge that could be rendered unfit by climatic conditions. Although there were some small production runs of noncorrosive ammunition for automatic weapons during World War II, it would not be until 1949 that noncorrosive primers would begin to be introduced on a regular basis. Beginning in 1953 all GI ammunition, with the exception of some lots of armor piercing and FA Match, would be noncorrosive. The last use of the corrosive FA Number 26 primer was in the FA Match of 1957.

The remainder of the pre war National Matches and regionals, held from 1931 to 1940, were fired with specially selected M1 bullets and cases, headstamped NM, using the standard powder load. National Match ammunition was ordered for 1941, using the M2 bullet, however the work was stopped within weeks of startup because production lines were needed to produce ball ammunition for more urgent military needs. For all intents and purposes production of National Match ammunition ceased after 1940 because of the United States involvement in both World War II and the Korean War and it was not resumed until 1957 when it was again produced and designated as T291.

Prior to World War II the ammunition was packaged 20 rounds to a box in four five round stripper clips. When production resumed the traditional 20 rounds of ammunition were packaged in the now familiar partitioned pasteboard box. In 1958, 30 Caliber National Match was designated as M72 and manufactured at Frankford until 1961. From 1962, until the production of National Match .30-06 ceased, the ammunition was fabricated at the Lake City Army Ammunition Plant.

The M1 Garand had been introduced to shooters at Camp Perry, in 1939, so it was with the M14 rifle’s debut. This new selective fire rifle, bearing a strong family resemblance to its predecessor, is chambered for the 7.62mm NATO cartridge and was adopted by the Army in 1957. It would soon be seen on the line at the National Matches and the production lines at Lake City would soon be churning out National Match ammunition to feed the new kid on the block.

The 7.62mm Match M118 cartridge was first approved for production in August of 1964 with the earliest runs produced at Frankford Arsenal. Since Frankford's closing Lake City has taken over all production, giving the ammunition its nickname of 'Elsie'. No relation to the Borden Company's 'contented cow', this homophonic simply refers to the cartridges’ head stamp, 'LC'.

Lake City Army Ammunition Plant, located 17 miles east of Kansas City, Missouri, was opened in 1941. It was one of the first government owned but contractor operated, ammunition plants to come into existence as the United States prepared for World War II. It presently covers almost 4,000 acres of land with all of the necessary buildings, ranges, and infrastructure required to produce small arms ammunition from 5.56mm to 20mm. It was briefly shut down in 1945. It was soon reopened and it has produced billions of rounds of ammunition for combat, competition, and training during its 55-year history.

Match cartridges have carried two headstamp notations in addition to the year of manufacture and the location. Some are marked 'NM' and others 'Match'. While all ammunition is manufactured to the same specifications, from time to time it was the practice to exercise additional care in the manufacture of the ammunition specifically earmarked for Camp Perry and the National Trophy Matches. These cases carry the 'NM' headstamp and are often packed in boxes that indicate that they are for use at Camp Perry. That ammunition was shipped to Camp Perry for issue on the line. The remaining stocks, head stamped 'Match', were delivered to the various military services and the DCM for use in training, service championships, other specific military needs, and EIC matches. More recently this practice has stopped and all ammunition carries a 'MATCH' headstamp.

The 1957 run of match ammunition at Frankford was boxed in a buff colored cardboard container with a red white, and blue printed label affixed to it. The label was the first use of the eagle logo superimposed upon the word match in red hollow block letters. The year and Frankford Arsenal also appear on this side. The top of the label carries the familiar "DISPOSAL OF EMPTIED CARTRIDGE CASES MUST BE MADE AS PRESCRIBED BY ARMY REGULATIONS". The obverse states that there are 20 cartridges of "CALIBER .30 MATCH” The lot number bullet weight and velocity are also noted. This box style would continue until 1962 when the now familiar white cardboard box appeared when production moved to Lake City.

The introduction of 7.62mm was heralded by a 1964 production run at Frankford using the familiar buff box design. The cartridge was designated as XM118 with a velocity of 2550 feet per second. The next year Frankford produced the ammunition with the buff box design and the cartridge's new designation of M118 while Lake City's 1965 white box design interestingly enough indicated that the contents were XM118.

M118 Match began rolling off of the production in white boxes. The year of production was noted by either having the year printed in red over the eagle logo or having the lot number, which first two numbers usually mirrored the last two of the year, stamped on the front just below M118. While this ammunition was a fine cartridge, it was impossible to stop shooters from tinkering with it to improve accuracy. As the military had the most ample supply of the ammunition the search for an extra edge started with them. For some time it was popular to take a pliers type reloading device and break the bituminous seal between the neck and the bullet in the belief that this would make the force needed to separate the bullet from the case more uniform. This was, of course, against the rules when the ammunition was being fired in an EIC or National Match.

Another tack taken by shooters was to pull the 173-grain bullet and replace it with a 168-grain hollow point boat tailed bullet. This modified ammunition proved better than the factory product and became very popular for use by military shooters in NRA matches. Like breaking the seal, replacing the bullet violated section 4-19 of the 'Rules and Regulations for National matches and Other Excellence-in-Competition (EIC) Matches' which forbids the alteration of the issued ammunition in any way. For reason lost to history this reworked ammunition became known as 'Mexican Match." This particular innovation was to influence a dramatic change in National Match ammunition.

In late 1979 and early 1980 rumors were ricocheting through the service rifle community about a new match cartridge to be issued that was a duplicate of the Mexican Match. There was a buzz of excitement at the ammunition issue points during the 1980 National Matches when the green metal cans were broken open and shooters were issued, for the first time, pasteboard boxes containing "20 CARTRIDGES 7.62 MM, PXR-6308 LOT LC-80F300S111 1980 NATIONAL MATCH BULLET 168 GRAINS VELOCITY 2550 FPS". A buff colored printed label covered the traditional white LC box. The top carried the usual disposal directions while the back side told that the contents were "SPECIAL MATCH CARTRIDGES FOR USE IN COMPETITIVE MATCH SHOOTING NOT TO BE USED IN COMBAT” The hollow pointed bullet, so accurate in competition, is forbidden, by the Geneva Convention, for combat use. To further identify the cartridge there was a cannelure that ran around the circumference of the case a short distance up from the base. There was much concern among the civilians that the shallow grooves would weaken the case and make it useless for reloading. The concern was not great enough to stop them from snatching up the gleaming bottleneck cylinders, almost before they stopped bouncing and steaming, from the dew dampened grass.

The ammunition proved very popular and was produced in 1981 as 7.62mm Match XM852. The LC boxes were still covered with a paper label but this one was in the traditional colors of red, white, and blue. However the familiar eagle had been dislodged from his perch and the word 'MATCH' was found in large hollow block letters on the back. The warning had been changed to "ATTENTION-THESE CARTRIDGES ARE FOR MARKSMAN AND COMPETITIVE SHOOTING-NOT FOR COMBAT USE-". In 1982 the ammunition was designated as M852 but still issued in a box with a paper label. By 1984 the new ammunition was packaged in its own Lake City box. The outline of a center fire cartridge, with an anachronistic round nosed bullet, faces nose down on each end flap. By 1991 the white box, American Eagle logo, and the case disposal message had passed into history, replaced by a plain brown box that carried a simple black frame on its front that enclosed the words, "20 CRTG. 7.62MM MATCH M852 NOT FOR COMBAT USE", on three lines, and a stamped lot number while the end flaps retained the round nosed cartridge motif.

In the mean time the M118 had not been forgotten. In 1983, when the M852 came out in its own LC white box M118 was relegated to a 20 round white box with a pasted over label. A black border surrounded the "7.62 MM NATO SPECIAL BALL M118" printed on the face while at the label bottom was the manufacturer, Lake City Army Ammunition Plant. A year later it could be found nestled in a new brown box. No longer the darling of the competitive shooter, it is still in the military supply system for training and combat use. The old match ammunition had served both competitive shooters and military snipers well. Still a good cartridge, it has found its niche and is destined to be around a long time.

Folk tradition holds that the buffalo was American Plains Indian's equivalent of the modern day shopping center. From the great woolly beast they took all the supplies that they needed to conduct their daily life. It is said that they used every part of the animal from nose to tail. Shooters have much the same relationship with National Match ammunition. The bullet and powder provide holes in the target as close to the center as the shooter can hold, the expended brass is reloaded, the empty wooden crates are reassembled and used to hold collected brass, put into use as makeshift stools, and serve as waste baskets on the line and in the huts. The wooden end panels are pressed into service as field expedient writing desks to hold scorebooks or scorecards.

Wise competitors save a few empty boxes in the shooting stool for a discarded box placed in the bottom of a shooting jacket pocket keeps a full box placed on top readily available so that while shooting off hand the ammunition is conveniently at your finger tips, rather than hiding deep in the pocket. On a rainy day a carton, with an end cut off, serves to protect the front sight blacking until it is time to shoot. When the targets come out of the pits a quick flick of the wrist discards the empty box as the shooter slides into position. About the only thing that might be recycled, and isn't, is the used primer but you can rest assured that there must have been at least one part of the buffalo that the Indians couldn't, or wouldn't, use also.

National Match ammunition has been a part of the shooting scene for the better part of this century. For those seeking to earn the Distinguished Rifleman Badge or a Presidents Hundred brassard National Match ammunition is like the Maltese Falcon in Dashiel Hammet's famous short story of the same name, it is "the stuff of which dreams are made". Economic and political circumstances have effected its production and distribution over the years and while its primer, bullet, and powder have changed the National Match cartridge remains the standard by which competitive ammunition is measured

Related Articles:
National Match Ammunition, by Ray Meketa
Lake City M118 Special Ball Ammunition, by Ray Meketa

Reloading: Audette Case Checking Method

Checking Case Wall Concentricity
by Germán A. Salazar

Original Creighton Audette Case Checker #46 - Owned by John Lowther

Introduction
It's been fifteen years since Creighton Audette left this earth, but his work still resonates among serious students of accuracy. Audette wrote many articles for this magazine and others, all of which I value very highly and have bound into a now well worn book. Several articles about the cartridge case's effect on accuracy led to this article and accuracy project. Those articles appeared in Precision Shooting and in the American Rifleman and described the importance of cartridge case wall concentricity and case head squareness (Cartridge Cases and Accuracy, Creighton Audette, American Rifleman, June 1981, p. 27 and January 1982, p. 30; Overlooked Aspects of the Cartridge Case, Creighton Audette, Precision Shooting, Dec. 1981. p. 21; Highpower Target Rifle Shooting, Creighton Audette, Precision Shooting, September 1986, p. 4).


Audette’s tests showed that cases with measurable variance in case wall thickness could, depending on their orientation in the chamber, produce shots significantly out of the group to the right or left. He then designed a tool to check case body wall runout, case head squareness and more. A version of case checking tool was patented by Roger Johnston of NECO (U.S Patent No. 5,301,436) and remains in production today. Another version of the tool, somewhat closer to Audette’s original design, is made by Tom Titcomb of CCG Firearms. Each tool has interesting features; however, we will work with the NECO tool for this article, focusing on its use in checking case body wall runout. Either tool will do a perfectly adequate job on these tests.


The CCG Firearms case checking tool.

Technical Background and Case Checking Procedures
The following paragraph from the NECO description of their gauge is a useful summary of Audette's findings, although I recommend that you obtain copies of the original articles for a thorough understanding of the subject:


"Normal manufacturing tolerances cause brass cartridge cases to vary in wall thickness around the circumference of their bodies. Under the stress of firing, a case with such variation stretches more readily along its thin side, transferring more pressure to the bolt face at that point and introducing an unbalanced force which contributes to bolt whip and vibration of the barreled action in its bedding. This whip and vibration varies from one shot to the next as cartridges are fired with their thin sides randomly oriented at different angles, causing reduced accuracy. The problem is made even worse if the brass is too hard or springy to completely fireform to the shape of the chamber, in which event the greater stretching of the case's thin side will cause it to develop a curve along the length of its body. These banana-shaped cases cannot hold a bullet aligned with and centered in the bore, undercutting the effectiveness of the handloader's careful case preparation."

The irregularity in thickness can be traced all the way back to the initial forming of the brass cups from which the case is drawn. Many factors, such as slight variations in the thickness and hardness of the brass sheet used to make the cups can result in this variance. Regardless of the care used in drawing the case from the cup, the variance in the case walls will never be less than the variance in the cup walls. Accordingly, manufacturers carefully monitor and limit cup thickness variance; Frankford Arsenal set its limit at 0.003", for instance. (See: Cartridge Manufacture, Douglas T. Hamilton, The Industrial Press, New York, 1916 at p. 61; Match Ammunition Manufacture at Frankford Arsenal, Walter Howe and E.H. Harrison, American Rifleman, December 1959, p. 15).


Audette tested different orientations of the thin side and concluded that orienting it vertically was the least problematic because the bolt lugs in a typical two-lug Mauser type action (Remington, Winchester, Springfield, etc.) are oriented vertically when closed and will be in a better position to counter the whip caused by the uneven case expansion. The 3:00 and 9:00 portions of the case head bear against the part of the bolt face that is not directly supported by the lugs. Orienting the thin spot in those directions will, as Audette demonstrated, result in wide shots to the respective side.

In my effort to learn from Audette's work, I began my work with the NECO-Audette tool; checking brass and conducting firing tests of ammunition with the sorted brass. Along the way, I learned a few things about the proper use of the tool which I hope will be of value to our readers.




Photo 1 shows the tool set up for case checking. The two support V-blocks on the right are just holding up that end of the tool, they serve no other functional purpose for this process (although they are essential for other applications of the tool). This view doesn't show the little L-shaped bar, the chord anvil, which comes out of the left side. The chord anvil rests on the inside of the case and the indicator tip is positioned "against" it on the outside of the case.


Photo 2 and 2A show a little more detail of the tool. You can see how the chord anvil comes out; you slide the case onto it and apply upward pressure so that the leg of the chord anvil bears against the inside of the case. The indicator is then rotated into contact with the exterior of the case directly opposite the chord anvil (they would touch if the case wasn't in between them). That leaves you with a setup that measures case wall thickness between the chord anvil and the indicator as you slowly rotate the case.


Photo 3 shows how I perform the case thickness checking process. You might find another way to hold things, but this is one way and it gives me very consistent results. It's important not to touch the rod holding the dial indicator as it is very sensitive. With the chord anvil pointing down and the indicator at the bottom of the case, you must maintain slight upward and leftward pressure on the case with the right hand - note that my index finger and thumb are forming a little V-block of their own.

One thing I learned early on is that this process works smoothly (literally) with new brass, but fired brass which has some carbon residue inside is a bit less smooth. The answer is to give the brass a few turns against the chord anvil before bringing the indicator to bear, that seems to scrape carbon off the inside of the case enough to allow the process to work better.

The other tip is that this is a SLOW process. You aren't going to twirl the case and see results. Work slowly - 5 or 6 moves to the revolution - as you make several revolutions, you begin to see the range settle down, you then determine the thin spot and mark it. I take about 2 minutes per case when doing a long run.




Photo 4. This is a Lake City 62 Match case that is the worst one I've run into so far; it has 0.009" runout at the base. Most LC 62 Match brass is very good, this one is the real exception to that. At this point, the case is just resting on the V-blocks for convenience; this position is not part of the gauging process. I mark the head with a line at the thin spot and write the amount of runout on the side. I don't expect the side mark to last, that's just for while I'm checking. When you run your thumbnail over the case where the solid web ends (where the pointer is indicating) you will feel a pregnant lump on the thin side of any piece of brass.  The bulge is always at the thin spot and is not dependent on the orientation of the case in the chamber when it was last fired.  On this case, the bulge is especially prominent as you will see below. Bear in mind that this case is full-length sized at the moment, not in "as-fired" condition so the bulge survives the sizing operation.






Photo 5. Dropping the case into a Forster case gauge, the 0.009" runout case will not go all the way in, even with moderate pressure (I didn't try to bang it in). What's interesting is that fired brass will slide in and out of this gauge easily, so it is certainly not smaller than my chamber. This piece of brass has been fired 4 times so far in my match rifle. I was obviously forcing the case into the chamber using the bolt as a lever. I don't remember having an especially hard closing case, but in the heat of a match some things go unnoticed. In any event, this case is clearly not one we can count on to perform to perfection.


Photo 6. This is a case with 0.003" runout; I have found that a case with runout as large as 0.007" will slide right into the gauge so this isn't an effective substitute for checking the case in the tool. Audette found that as little as 0.002" case wall runout had a measurable effect on accuracy and that 0.003" was the maximum that could be reasonably used. He also mentioned that Lake City brass showed more variance and a greater range than the commercial brass he checked with just over half of the Lake City showing runout of 0.003" or less. Based on those findings, I set my maximum allowable runout at 0.003".

Checking Brass and Testing
Using the method described above, I checked two sets of my match brass. A set, in my book, is 70 cases, which is just enough to get through a 60 shot prone match with 6 sighters and a few extra pieces. The first set was Lake City 62 Match and the second set was commercial Winchester of recent manufacture. When Lake City geared up to take over production of Match ammunition from Frankford Arsenal in 1962, they worked diligently to make that ammo the best 30-06 that had ever been produced and based on the accuracy they obtained in comparison to previous years, they succeeded. Case wall runout was one of the items Lake City's engineers focused on, and in order to minimize runout, the cases were made with four draws instead of the usual three draws or even the two draw method which Frankford Arsenal pioneered (National Match Ammunition, E.H. Harrison, American Rifleman, August 1962, p. 22; Match Ammunition Manufacture at Frankford Arsenal, Walter Howe and E.H. Harrison, American Rifleman, December 1959, p. 15). Despite their efforts, I found that 12 of the 70 pieces in the set I was using had runout of 0.004" or greater with the largest being the case with 0.009" runout mentioned earlier. Of those twelve cases, eight were just at 0.004", however. This is a quite a bit better than Audette found in his sample of LC 64 Match 7.62 brass, but as you will see, not quite as good as modern commercial brass.

The second set of brass was commercial Winchester; however, it was not exactly fresh from the bag. These cases were picked up at the range over a period of time and came from many different manufacturing lots. It is a true testament to Winchester's quality control that of those 70 cases, made over several years, only four were rejected for excessive runout and those four cases were at 0.004" runout, just over our acceptance level.

In the three months preceding this project, I shot those two sets of brass in three matches each, most at 500 yards, one at 600 yards, all prone, iron sights. The loads used were not always identical from match to match, but were similar with various Sierra and Lapua bullets in the 180 to 190 gr. weight range and H4350 powder. Scores with the Lake City brass were 595-29X, 596-37X and 595-38X for an average of 595-35X. With the Winchester brass, the scores were 598-30X, 594-32X and 596-32X for an average of 596-31X. Overall, the scores were fairly consistent; my notes indicate that the low score with the Winchester brass was fired on a day that was especially windy, even by Phoenix standards. My plan was to fire the sorted Lake City brass over the next three weeks to see if the scores showed any improvement.

July 5, 2009 - 500 Yard Test
The first test was a prone, iron sight, match at 500 yards at the Phoenix Rod & Gun Club. The rifle fired was the Remington 700 based Competition Shooting Stuff RT10 in 30-06 which I described in the Gun of the Week 91 article in Accurate Shooter. The rifle has just under 1000 rounds fired through it's 1:11" twist barrel; the load was Lake City 62 Match brass, PMC (Russian) large rifle primers, H4350 and Sierra 180 gr. Match King bullets which were moly-coated using the NECO process and pointed using the Whidden pointing tool.


Under somewhat difficult conditions - 110 degrees and a gusty wind at 5 to 12 mph - I shot a 598-36X (199-12, 199-13, 200-11) with no mystery shots whatsoever. This is the best score I've fired with this brass in this rifle and a satisfying payoff for the effort expended. After finishing the first string, I fired the case with 0.009" runout, orienting the thin spot to 9:00 in the chamber to maximize the effect. The shot was a wide 10 at 8:00, so it wasn't as horrible as I feared it might be, but following on two centered X's just before, it was definitely out of the expected area of impact.


July 12, 2009 - 500 Yard Test
Unfortunately, Part 2 of the test didn't go as well as I might have hoped. With the temperature in Phoenix at 115 degrees and the wind blowing fairly strongly, this was not an ideal day to explore the potential of a subtle change in ammunition. Our club has a section that operates as a public range and that was closed due to an extreme heat advisory. Highpower shooters being somewhat hard-headed, we donned our shooting coats and pressed on with the match. I had a fair number of vertical shots and some cases were giving hard extraction; these were likely symptoms of heat induced pressure. To make matters worse, several cases separated near the base, this brass has been fired twelve times and it finally gave out. Due to the head separations, I scrapped this set of brass and will have to start over with some fresh LC 62 Match.

Scores for the match were 198-7X, 199-8X and 198-9X for a 595-24X which is a respectable enough score, but certainly not up to the potential we've seen from this rifle and ammunition. Despite the disappointment, the average score for the two matches with the sorted cases was 1.5 points higher for the aggregate than the average with unsorted cases and a bit higher than with the Winchester brass which showed very good runout. While I would have liked to shoot three matches with the sorted cases, 120 record shots is still a reasonable number with which to see a trend developing.

I believe this test indicates that the case sorting and indexing has value and since it is a one-time operation for each set of brass, I'll continue to do it. Some procedures are of immediately apparent value, others, perhaps including this one, show their value over time with a small increase in scores or X count and at a certain level, small increases are all we can look for.

Concluding Thoughts
The process of measuring runout was relatively simple and took about two hours per set of 70 cases. It was satisfying to find those cases with excessive runout and cull them, knowing it would be beneficial to future scores - at least mentally. What I found hardest, predictably, was orienting the thin side straight up as Audette recommended, when loading the ammo into the rifle. I would take the case out of the box, spin it so that the thin spot was as 12:00 and then insert it in the rifle. This is the point at which I lost track of the orientation since I can't see into the loading port with the rifle in my shoulder (I don't remove it to load). Nonetheless, I think that most of the cases were between 1:00 and 11:00. Previously I performed a test that showed me that the cases don't rotate on closing the bolt, so I'm reasonably confident that they went into the chamber in the orientation in which I placed them in the loading port, which was somewhat imperfect, but close.

One may wonder whether the effort expended on this 47 year old brass, however successful, is warranted when new commercial brass is much better. That is a question each of us must answer for himself, and for many the answer is a resounding yes. Not all precision shooting is done with a 6PPC at 100 and 200 yards; many of us shoot longer distances with larger cases. Those larger cases need more care and attention because the longer a case is, the more difficult it becomes for the manufacturer to maintain uniformity of case wall thickness. Further, for some of us, there is an added pleasure in shooting high scores with old brass and bullets, shiny and new isn't always the most satisfying approach. There is a craft to precision reloading and precision shooting and knowing how to get the most out of the components at hand is part of that craft.

Creighton Audette was fond of asking "What do you know, for sure, today?" That can be a tough question to answer for an analytical person; but I know, for sure, today, that my interest in cartridge cases and particularly case thickness now extends to the regions below the neck which I previously ignored.

Related Article:
Indexing Cases

Suppliers:

NECO
http://www.neconos.com/
108 Ardmore Way
Benicia, CA 94510
1-800-451-3550

CCG Firearms
Tom Titcomb
5217 E. Belknap St.
Haltom City, TX 76117
http://www.ccgfirearms.com/
1-817-834-9554
1-800-819-7464


 

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