Sport Pistol powder in 45acp.

[Jim Watson]

I went around similarly with Titegroup when it was new on the market. It was less position sensitive than W231 but more than 700X.

I was "working down" .45 ACP loads to minor power factor to spare my arthritis and flinch. Bullseye was the most consistent at very light loads. Or maybe the least inconsistent, 650 fps is not a common regime.

 

[LiveLife]

Sport Pistol RMR 115 RN Plated, Winchester small pistol primers, seated to 1.145”. Shot from Witness Elite 4.75” barrel

4.7gn, 1154fps, 14.0sd, 46.3es
4.8gn, 1177fps, 9.2sd, 22.5es.

It looks like Sport Pistol is much happier at the higher pressure.

Try 4.8 gr load with shorter 1.135" OAL and see if SD and group size decreases. If group size decreases, consider testing 1.130" and even 1.125" (I went all the way down to 1.110")

Disclaimer: Following load was developed referencing Alliant +P load data. Use at your own risk - https://www.alliantpowder.com/reloaders/powderlist.aspx?type=1&powderid=42&cartridge=189

• 9mm 115 gr FMJ Sport Pistol COL 1.120" Max 4.8 gr 1,151 fps

• 9mm 115 gr Speer TMJ RN Sport Pistol COL 1.135 Max 4.8 gr 1,164 fps

• 9mm 115 gr Speer CPRN Sport Pistol COL 1.135" Max 5.0 gr 1,171 fps

• 9mm +P 115 gr FMJ Sport Pistol COL 1.150" Max 5.1 gr 1200 fps

• 9mm +P 115 gr Speer TMJ RN Sport Pistol COL 1.135" Max 5.2 gr 1,229 fps

• 9mm +P 115 gr Speer CPRN Sport Pistol COL 1.135" Max 5.4 gr 1,225 fps

For my Sport Pistol testing, 4.8 gr at 1.110" OAL showed promise for greater accuracy - https://www.thehighroad.org/index.php?threads/new-alliant-sport-pistol.816514/page-5#post-10598431

 

[Toprudder]

I was "working down" .45 ACP loads to minor power factor to spare my arthritis and flinch. Bullseye was the most consistent at very light loads. Or maybe the least inconsistent, 650 fps is not a common regime.

700 fps is about as slow as I like to go, I have one gun Witness steel frame) that seems to be most accurate at 700fps, regardless of which combo of powder and bullet I use.

Try 4.8 gr load with shorter 1.135" OAL and see if SD and group size decreases. If group size decreases, consider testing 1.130" and even 1.125" (I went all the way down to 1.110")

For those bullets (RMR plated 115 RN) they feed most reliably, for me, at that COL. I may try slightly shorter OAL and see how they do. I also need to check for group size, I was not able to check for accuracy this go around.

 

[DanK3Pos]

I was able to make it to the range to do some more testing with Sport Pistol.

I made up some 45acp test rounds, all using 6.2gn powder, 200gn plated bullets, and WLP primers. I used my Chargemaster to dispense the powder, so the loads were reasonably uniform. I shot 10 rounds, the first 5 were “powder forward”, I held the gun barrel-down before shooting. The last 5 were powder rear.

The overall stats for all 10 shots were 828.9 avg, 74.0sd, 204.8es.

The first 5, powder forward: 761.6 avg, 23.8sd, 63.0es.

The last 5, powder rear: 895.8 avg, 22.9sd, 59.0es.

Difference between forward/rear = 134.2 fps.

If not for the case-position sensitivity, the stats are acceptable, but overall they are not, IMHO.

I also made some test loads in 357 mag, were I saw an average of about 85 fps difference between forward/rear. I’ve seen a lot worse powders. I suspect the heavy roll crimp helped mitigate the position sensitivity.

You've seen worse, but have you seen better? I guess the take away is you are better off with a full case so that forward/rear doesn't matter so much.