Yesterday saw me doing accuracy and chrono work for the Girsan 1911SC. Protocol was to chrono 10 consecutive shots from three separate batches/brands of ammunition with different bullet weights. Each of those loads was then tested for accuracy for three consecutive 5-shot groups at 15 yards from a rest.
For the test, I used Winchester White Box 124gr FMJ, PMC Bronze 115gr JHP, and Federal Premium HST 147gr JHP.
- Winchester White Box 124gr FMJ, advertised velocity 1200 fps.
- Average velocity: 1095.8
- Low: 1070
- High: 1109
- PMC Bronze 115gr JHP, advertised velocity 1160 fps.
- Average velocity: 1038
- Low: 1024
- High: 1054
- Federal Premium HST 147gr JHP, advertised velocity 1000 fps
- Average velocity: 939.3
- Low: 922
- High: 964
Interestingly, the PMC Bronze was the most consistent performer of the three, with only a 30 fps spread between lowest and highest velocity. The Federal Premium HST was the least consistent of the three, with a spread of 42 fps between lowest and highest velocity.
All loads chronographed lower than advertised through the MC1911SC’s 3.4″ barrel. WWB was 104.2 fps slower, PMC Bronze was 122 fps slower, and the Federal Premium HST dropped off the least, at only 60.7 fps slower.
Groups averaged 4.0″ with WWB, 3.25″ for PMC Bronze, and 3.75″ for Federal Premium HST. I was pleasantly surprised at the performance of the PMC Bronze ammo. It might be worth testing terminal ballistics on this load on some gelatin, to see how in performs in FBI barrier tests.
As always, a big thanks to Lucky Gunner for the ammo to conduct these tests.
Overall, 300 rounds were fired, with three failures to lock back on the last round of magazine #6 (WWB, round 45), magazine #8 (twice, PMC Bronze, rounds 110 and 140). There were no other malfunctions to report.
For those of you keeping score at home, that’s 770 rounds fired, with three failures to eject and two failures to fire, all within the first 250 rounds. 1,230 rounds to go.