Strangely, I had never before loaded 147-gr bullets in 9x19mm. Decided to change that.
Got some 147-gr X-Treme CPRN bullets to load. Chose W-231 powder at 3.4/3.7/4.0-gr rungs on the ladder. Used both CCI-400 SRP and WSP(m) for primers. Took data about 10' from muzzle and used 10 shot strings each. All rounds fired from a S&W M&P EZ 9. Overall length right around 1.145".
Meteorological data = 74 F, 63% RH, 29.80" Hg
9x19mm Luger 147-gr X-Treme CPRN@1.145" COAL
S&W M&P EZ 9 with 3.7" barrel
W-231 Pistol Powder & CCI-400SRP:
3.4-gr - AVERAGE = 803 fps - ES = 31.8 - SD = 9.7
3.7-gr - AVERAGE = 860 fps - ES = 26.1 - SD = 7.6
4.0-gr - AVERAGE = 874 fps - ES = 23.6 - SD = 7.1
W-231 Pistol Powder & WSP(m):
3.4-gr - AVERAGE = 795 fps - ES = 58.8 - SD = 19.3
3.7-gr - AVERAGE = 822 fps - ES = 47.8 - SD = 12.9
4.0-gr - AVERAGE = 889 fps - ES = 34.1 - SD = 10.5
Thoughts - I find it interesting that in this head-to-head comparison the SD was always tighter with the CCI-400SRP than with the WSP(m). Not that the WSP(m) SD was bad, mind you, just not quite as good as the other.
At the end of the day I am looking for a load that will still be subsonic out of a 16" carbine barrel. I suppose my next stop on this train will be to load more of those 4.0-gr selections and chrono them through my carbine. I just wanted to first make sure that they all ran fine in a compact gun and they all did.