[Grouse Chaser]

Alex, I’m posting the below two trials in-line on your Alliant Sport Pistol thread. Slightly lighter loads by a gradient of 0.1gr and 0.2 gr.

*Although load variables are slightly different; and your CZ at 4.6″ probably has a much tighter chamber/shorter throat than my Beretta 4.9″ loose chamber/very long throat, it’s interesting to see the results compared. Fairly predictable velocity as pressures ramp to published max.

*Yours at 4.4gr/1.100″ — 1091 fps
Mine: 4.3gr / 1.110″ — 1032 fps
and 4.2gr / 1.110″ — 993 fps

Observations: 4.2gr felt good but unsurprisingly, the ramp to 4.3 felt only slightly snappier but benefited by notably improved SD/ES, and slightly improved groups–a pattern I’ve seen before with Alliant SP. (general forum precaution note: Alliant’s published data shows 4.4gr max / generic 124 JHP @ 1.120″)

Description: 9x19mm RMR Matchwinner Jacketed FP 124gr
Notes 1: Alliant Sport Pistol 4.3gr / COL 1.110″ /WSP/ Herters (These were Cabela’s S&B produced era brass) once fired cases
Notes 2: Beretta 92 (stock – early 90’s production)
Bullet Weight (gr): 124.000
Temp: 57F
Shots: sample size: 10 rounds

Average: 1031.70
StdDev: 15.09
Min: 1001
Max: 1048
PF: 128
___________________________________________

Description: 9x19mm RMR Matchwinner Jacketed FP 124gr
Notes 1: Alliant Sport Pistol 4.2gr / COL 1.110″ /WSP/ Win Cases
Notes 2: Beretta 92 (stock – early 90’s production)
Bullet Weight (gr): 124.000
Temp: 57F
Shots: sample size: 10 rounds

Average: 992.56
StdDev: 24.60
Min: 935
Max: 1018
PF: 123

[Grouse Chaser]

Below is a medium-heavy load with the MPR JHP 124gr in 9×19; (I’ve also run a few trials with RMR’s TCFP 124 Matchwinners which I’ll post to that thread).

If helpful:
–I ran these @1.109″ (knowingly long for this bullet’s profile). I have some ready-to-test @ 1.0875″ / down-loaded to 5.0 gr BE-86.
–Just my experience, but with PISTOL loads I find more accuracy contribution from low SDs (which is often easier to achieve with moderately shorter COLs) than I do with fretting about the jump gap to rifling.
–Below shot at 7 yards rested on a towel. Not really a meaningful distance to measure accuracy…but all 10 shots were just about covered with a half-dollar.

Description: RMR MPR JHP 124gr
Notes 1: Alliant BE-86 5.3gr / COL 1.109″ / WSP/ Herters (These were Cabela’s S&B produced era brass) once fired cases
Notes 2: Beretta 92 (stock – early 90’s production)
Distance to Chrono (FT): 10.00
Bullet Weight (gr): 124.000
Temp: 57F
Shots
# FPS FT-LBS PF
10 1104 335.64 136.90
9 1109 338.69 137.52
8 1103 335.03 136.77
7 1084 323.59 134.42
6 1070 315.29 132.68
5 1075 318.24 133.30
4 1083 322.99 134.29
3 1105 336.25 137.02
2 1091 327.78 135.28
1 1087 325.38 134.79

Average: 1091.10
StdDev: 13.58
Min: 1070
Max: 1109
Spread: 39
True MV: 1092.34

• This reply was modified 3 years, 4 months ago by Grouse Chaser. Reason: added relevant info

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