Well, I did it finally! Found the place where I need to step back a little. Fired a round today and thoroughly smacked the 1200 fps barrier and had a couple rounds that cracked 1300 fps. The downside is that I will not revisit these loads again due to a number of issues I will explain in the following text.

Loads today were fired with RCC brass, Federal small pistol primers and the bullets lubed with NASA lube. There were 4 test loads of 3 shots each and detailed data follows:

Fouler rounds: 5 shots CCI SV Avg 1080, ES 42; Sd 16
Load #1: 1.2 grains of Bullseye; 1309, 1294, 1269 fps Avg 1290 fps; ES 40; Sd 20
Load #2: 1.1 grains of 700X; 1219, 1230, 1241 fps Avg 1230 fps; ES 22; Sd 11 - One case lost due to expanded primer pocket
Load #3: 1.3 grains of WW231: 1289, 1267, 1304 fps Avg 1286; ES 37; Sd 18
Load #4: 1.1 grains of Red Dot: 1269, 1266, 1243 fps Avg 1259; ES 26; Sd 14 - One case lost due to expanded primer pocket
5 rounds followup with CCI SV: Avg 1063, ES 30, Sd 12

In the image that follows it is apparent the primers were flattened and is some cases there was gas leakage around the primers. The cases are organized L-R in the order referenced above.

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All case diameters immediately forward of the rim expanded .001-.002". All primer pockets expanded to some degree though most are still usable. The charge increase was only .1 grains from the previous exercise (8-9% charge increase) and it appears there was a corresponding velocity increase though not necessarily linear. Extraction ranged from slight to moderately stiff.

One likely candidate for why this happened is the matter of case volume. The .22 GTC cases have a volume of approximately .012 cubic inches from web to bullet base, whereas industry RF ammo is about 40% greater, at .017 cubic inches. Load densities for the loads above ranged from 95-98%+ to approximately 102% (WAG) for the Red Dot load. It is reasonable to assume there is a correlation between this and running head long into the pressure wall. A possible co-conspirator is the crimp put in place after annealing the brass, but I'm somewhat skeptical about that influence. It is fair to say the previous round was not tightly crimped at all, but this one was reasonably firm. About .002" of taper crimp for the record.

The rounds were sure 'nuff crackin' each time I pulled the trigger though. laugh In fact they were having so much fun they seemed to have forgotten the road map.

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I will step back and load the previous round's charges with the crimp and see what the results of that are....mebbe even fall back to the CCI primers for giggles.

That is all for the time being. I've got to tear down the log backstop and put up something a bit more rot resistant. I'm guessing it will be 3 weeks or so before that is finished.

I am..........disturbed.

Concerning the difference between man and the jackass: some observers hold that there isn't any. But this wrongs the jackass. -Twain