This article detailing the preparation of the 1923 National Match rifles comes to us from the Army Ordnance journal, presenting a true insider's view of the production of these highly coveted rifles. - GAS -
Special Features of National Match Rifles
by, S. H. MacGregor
It has been contended, for a long period, that in the spring various fancies turn in various peculiar ways. The first robins arrive with a reveille call for hibernating hobbies. Enthusiastic riflemen commence to figure on the probable date of the National Matches and there is a stir of action towards collecting an array of time tables, summer resort guides and kindred publications.
Naturally enough the wise man, whose business it is to prepare time tables and resort guides, has anticipated this perennial return of hope and has prepared his wares in advance. In a similar manner the results of the past year at Camp Perry have been studied and plans laid in advance for the production of the rifles which are to comfort the hearts of those who will compete this year.
And when these things happen the marksman is often prone to lay the blame on the gun. An examination of the sights, a careful scrutiny of the base and sides of the offending cartridge case often indicate that the wild shot must be laid to some unknown cause, some sudden fancy of the elements - a lapse in the wind and, sometimes, perhaps, too often, to some idiosyncracy of the rifle. Too-seldom it is the admitted fault of the rifleman.
And perhaps for the very reason that our human weakness causes us to look about for an external cause, we have from time to time examined into possible causes in the rifle. Thus we have gradually worked out dimensions and characteristics which are such as to minimize errors of material. Having arrived through many experiences and many years of investigation, at ideal requirements, and having measured these against fundamental requirements pertaining to weight, balance and form of military weapons, we have arrived at the specifications for National Match rifles which represent the present authorized military arm of our service in its most accurate and refined state.
The National Match rifle is the service caliber .30, Model of 1903, manufactured under special conditions of care and workmanship. The important dimensions are as specified for the service rifle except as to tolerances which are closer. Some changes are made in the trigger mechanism and the trigger pulls are made lighter.
Accuracy will depend largely upon the barrel construction and it is with barrels that the greatest care is exercised. Specially selected stock is used and boring and reaming is held to a minimum in order that the rifling operation will not exceed limits. The last reaming produces a barrel between .2999 and .3000 inch and the rifling operation brings the dimensions to, bore .3000 to .3005, and grooves .3080 to .3085. In any barrel the variation in dimensions must not exceed .0001 inch.
|Figure 1. Gauging a Barrel During rifling|
In figure 1 is a rifler carefully gauging a barrel which has been in the rifling machine long enough to have approached very near to the finished dimension. This machine, equipped with a double scrape cutter, rifles a barrel in about one-half hour. So fine are the chips or scrapings that, as they are collected in the end of the machine, they resemble oil-soaked waste. The metal is in such a finely divided form and so soaked with oil that care must be taken to remove the cuttings frequently in a covered receptacle to prevent spontaneous combustion.
|Figure 2. A Rifle Machine Operator |
Examines His Work
Between riflings, the scrape cutters are examined under a glass and carefully stoned to the proper curve and to a keen edge. This stone is almost as smooth as a baby's cheek, yet so much care is exercised in this operation that only one or two strokes of the stone are taken before an examination of the edge is made with a magnifying glass. How many riflemen who cling to the old straight razor would take this much care with the edge of the instrument which is to scrape their faces?
The result of this careful stoning is a very smooth barrel and one that is accurate. Figure 3 shows a sample target fired at 200 yards from a muzzle rest. The dispersion is 1 1/2 inches vertical and 1 1/4 inches horizontal. A sample star gauge sheet shows the diameter of lands .3000" and of the grooves .3082" without variation throughout.
|Figure 3. A Target used to Target a National|
Match Rifle at 200 Yards
At Right: A SampleStar Gauge Tag
Chambers are as near minimum as possible and headspace must be from 1.940" to under 1.944". A headspace of 1.944" is cause for rejection. This headspace requirement must be fulfilled after proof and function firing, because a slight setting of parts will cause headspace to be greater after function firing takes place than before.
Cocking pieces are given a case-hardening that will produce a case of about .012 inch. This case is made heavier in order to allow the nose to be stoned to individual taste without getting through into the softer material. Some difficulty has been encountered in previous years because inaccurate stoning often produced a soft wearing surface and consequently an easily worn-out component. With an increased case it is expected that a greater amount of stoning will be possible without undesirable results.
|Figure 4. Testing Front and Rear Sight Bases |
In figure 4 an inspector is checking up the sight bases. His fixture holds the barrel by two plugs, one in the muzzle and one in the breech. A straightedge is brought down on the front stud and the barrel rotated to bring the surface of the stud horizontal. The surface of the fixed or rear sight base is then tested with the straightedge fixture seen at the right end for height and for distortion with reference to the front stud. This is a very delicate adjustment and ensures that the sight bases are parallel and at the proper height above the line of the bore.
|Figure 5. Inspecting National Match Barrels|
Figure 6 shows how National Match rifles are targeted. Expert shots are used for this work and one man is able to shoot about 15 or 20 rifles per day. More than this number per day for a long period would produce undesirable physical strains which would tell on the quality of the work.
Having followed the specifications for National Match rifles very closely, there is produced a weapon which has a barrel as accurate as it seems possible to make it, a bolt which is polished for smooth action in a polished receiver and therefore quickly and easily operated, the minimum headspace to eliminate inaccuracies from that cause, a carefully gauged mainspring to insure quick ignition after releasing the firing pin, a smooth, fairly light trigger to eliminate pulling off the target and other less important features which in combination represent the ideas of good shots. At the same time the rifle is essentially the service rifle, the manufacture of which is being improved each year as greater ease is attained in the manufacture of National Match rifles.
|Figure 6. Targetting National Match Rifles|
It is interesting to note that the workmen who combine to produce these rifles take so keen an interest in the work that they feel a personal responsibility in the performance of their product at the Matches. These men, many of them approaching 30 years of Armory service, are expert at their vocations. Their entire lives have been spent in working up to their present expertness and their workmanship is typical of the master craftsman. To them the failure of a rifle to make a good record is an indication of failure on their part and for this reason they jealously guard their work against any possibility of inaccurate or incomplete inspection.
With a spirit like this it is safe to assume that National Match rifles will improve each year.