Can't remember if it was this thread or a different one that I promised to post results from 8mm ammo testing, but I've now got the data so here it is.
Bullet: Hornady Interlock Spire Point, .323" 150gr
Brass: Remington 8mm Mauser
Primer: CCI 200 Lrg. Rifle, Lot F16C
Powder: 52.0gr AA 2520 Lot 18497
OAL: 3.003"
Rifle: T38 Turkish Mauser (mfg. 1941), 8x57JS
Barrel Length: 29.5"
Tested at: Desert Trails rifle range, Tucson AZ
Elevation: ~2500 MSL
Date Tested: May 23, 2004
Temp: 95F
windy but clear
Chronograph Distance: 10'
Shot No. Velocity (fps)
1 3,027
2 3,003
3 3,015
4 2,990
5 2,998
Average: 3007 fps
Std. Dev: 14.6 fps
Extreme Spread: 37 fps
As a comparison to the mil-surp Turk ammo that I've got, here the chrono data from the rounds we did on Saturday. Same location, same rifle. Temp during testing was 98.6F, again windy but clear. Chrono was again at 10'.
Bullet: 154gr FMJ spitzer
Brass: Turk military
Primer: Berdan style, corrosive
Powder: ??
OAL: Not measured
Shot No. Velocity
1 2,992
2 3,003
3 2,999
4 3,036
5 3,002
6 2,980
7 2,963
8 2,968
9 3,017
10 2,983
Average: 2994 fps
Std. Dev: 22.2 fps
Extreme Spread: 73 fps
An observation: The Turk ammo must be one of: Much higher pressure, or much softer brass, or some combination of the two. The rounds loaded by my FFL had no extraction issues, and the primers were barely flattened, with no sign of cratering. The Turk ammo began having extraction issues after just a couple rounds (hard to get the bolt all the way up) and had significant cratering in the primers.
The Turk ammo seems surprisingly consistant based on standard deviation. I would like to chrono a bunch more rounds and get a large sample (30 or 40 rounds) to get a better idea of the real quality. It would also be interesting to see how the group sizes compare to the loads from my FFL. Once I get either Mojo sights or a pistol scope on the rifle, I'll have to do that experiment.