In 1937, Frankford Arsenal loaded Cal .30 Palma Match ammunition consisting of the 172 grain M1 Type (smooth) bullet in cases headstamped FA 37 P. With an average velocity of 2840 fps, 1000 yard accuracy was measured at 5.89" mean radius, slightly better than typical Palma ammunition of the period.
At the same time, comparison tests were conducted with several similar loads. Both regular and high pressure test cases were loaded with plain and stannic stained M1 Type bullets, and regular cases with plain and stannic stained M2 bullets. It was noted that the velocity and chamber pressure were nearly always higher than normal with the stannic stained bullets.
These “comparison” cartridges are not often seen in collections, because they are relatively uncommon, and because they are often overlooked due to their similarity to the conventional Palma Match, M1, and M2 cartridges. Shown below is a standard load and one of the comparison loads with the M1 Type Stannic Stained bullet.
Frankford Arsenal must have anticipated selling the excess M1 Type Stannic Stained bullets because they were boxed in 100 count cartons, labeled as PALMA MATCH - STANNIC STAINED. However, because the comparison tests resulted in high chamber pressures, it must have been decided to withdraw them from circulation, de-tin them, roll a crimping cannelure, and re-box them as conventional M1 bullets. The original labels were re-used, with the reference to Palma Match and Stannic Stained covered with a piece of black tape. One such carton, without the tape, is shown below.
If anyone has one of the original cartons of bullets, I’d really like to hear from them.