1927 National Match Ammo

[Cosine26]

These pages are copied from the American Rifleman for October 1927. It indicates that the 1925 Nation Match Ammo was used for the 1927 match. What surprises me is that the cleaning instructions indicate that bore deposits require special cleaning. I thought that the gilding-metal biullet eliminated the bore fouling.

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[raymeketa]

The article indicates that the problem was with uneven tin fouling from the powder. That's interesting because the powder used in the 1925 NM ammunition was IMR 1147 and it did not contain tin, as far as I know. But, after the "tin can ammo" fiasco of 1921 maybe F.A. added tin to the powder?

Ray

[mhb]

that the tin fouling comment applied to the 1925 ammunition at all - there is no apparent continuity between the separate pages shown in the photos (no page numbers, etc.), while the text specifically says that there should be little or no lumpy metal fouling experienced with the GM jacketed M1 or NM bullets, and the cleaning instructions do not address difficult metal fouling..
The only NM ammunition known to have given the lumpy tin fouling was the 1921 NM, with tin-plated bullet. Tin-incorporated powders were made, but I do not know of any use of them in NM or ball ammunition - these were the '-1/2' series of MR powders - 1147 did not include any tin in its composition.
It seems most likely that the tin fouling comment was in regard to the 1921 ammunition.

mhb - Mike

[Cosine26]

The entire article occupies about eight pages and I did not want to post all of them. I excerpted the paragraphs pertaining to ammunition used at the 1927 Nationals. Picture no 2 which begins with "Getting back to the equipment..." is a follow on to the picture to no 1 and really refers to the finish of the rifles and then goes into metal fouling of the bore. I believe that the author is referring to the older M1906 bullets or match ammo of the pre war years, but he does not make that clear. His later cleaning instructions for the NM1925 ammo does not indicate any fouling problems other than the corrosive priming. At that time I do not believe that the corrosive ammo problem had been solved. I believe that time came about 1928. The early 1930 NM ammo had a non-corrosive Berdan primer which developed pressure problems during the initial firing trials . Corrosively prime ammo was subsumed for the 1930 matches. I do not believe that the 1921 NM ammo left metal fouling in the barrel even with the tin plated bullet. I believe that the tin plating was designed to eliminate the metal fouling. The big problem with the 1921 NM ammo was use of MobilLube.
I just wondered if I was missing something. I think that the problem is the lack of clarity of the paragraph in picture no 2.
FWIW

[mhb]

including match types, the corrosive priming issue was not finally resolved until the 1950s, the 1930 experiment having proved unsatisfactory. Even some of the first batches of match ammunition in 7.62mm were corrosive primed, I believe.
I am aware that the 1921 match bullets were tin-plated to prevent CN fouling, but believe that tin fouling contributed to the continued use of Mobillubricant, in spite of very specific instructions given at the matches not to do so.
Lumpy tin fouling was definitely a problem with the original issues of the tin-incorporated powders - enough so that the percentage of tin was drastically reduced, and, with the passing of the CN-jacketed bullets, such powders were no longer useful, and were discontinued.
In any case, the adoption of GM for jackets eliminated the metal fouling problems experienced with CN jackets, and the use of tin and/or grease on the bullet soon passed away with them.

mhb - Mike

[raymeketa]

The 1930 non-corrosive primer experiment by F.A. failed only in the sense that someone in authority made a hasty and unwise decision, and blamed it on the weather. There was absolutely nothing wrong with the ammunition. By 1930 the major commercial manufacturers were using non-corrosive primers and the Berdan primer with non-corrosive mixture was being used in many parts of the world that experienced far greater temperature extremes than at Camp Perry. That bad decision set the non-corrosive primer in U.S. military ammunition back 20 years.

Only the first two lots of the 7.62mm Match T275 ammunition were primed with the old corrosive primer. That was another unwise decision by someone who must have believed the myth that corrosive primers gave better accuracy. The error was soon corrected and that was end of both the myth and the corrosive primer.

Ray