Winchester Super Target (WST) shot-to-shot variation

rg1911

Gunny Sergeant
Full Member
Minuteman
Oct 24, 2012
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Laramie, Wyoming
I was working up some new loads for a new cast bullet for my .45 1911. The loads all used prepped WW brass, WW large pistol primers, and weighed charges of WST. The temperature at the range yesterday was 90 degrees F.

Over my Oehler chronograph, I was seeing shot-to-shot variations of up to 112 fps.

This seemed a little extreme for individually-weighed charges. Is WST known to be erratic?

Thank you,
Richard
 
I can't find my initial work-up data for WST in 45 ACP, but I really like this powder for pistol.

I wouldn't worry too much unless you intend to use the loads for Bullseye.

Likely to be a combination of chrono error plus just normal variation in the rounds.
 
You should be able to keep pistol SDs in the teens, even with mixed brass and dropped charges.

Even with meticulous preparation, velocity spreads will open up if the powder just isn't happy in the pressure range you're trying to operate it in. Slow powders may not be able to generate enough pressure in 45 acp to really work consistently because the maximum pressure is only 21 ksi. Target loads and light bullets in that caliber are even more of a problem. It's a great caliber, but it's a little different than most other common pistol rounds.

Bullseye is a relatively slow powder for full power 45 acp loads, and it's fast for just about everything else. Not sure where WST fits in the burn rate chart.

I'd get SDs in the 12-14 range with 45 acp mass produced for IDPA. Not great, but not bad enough to fool with much more. My 40 and 9 loads were single digit.
 
Sounds like the burn rate is about right for mid range 45 loads.

It might still give trouble at the top and bottom of the recommended load range. If you're at the bottom of the load range, maybe bump it up 0.2 grains to see if it settles down. If you're at the top, go the other way.

What was the charge and what velocity did it give?

After that, maybe a different primer.
 
I have loaded thousands of round using WST. .45, 9mm and .38 special. Never had the deviation you are describing. my go .45 load was 4.6 grains of WST with 200 grain swc. 1.250 OAL. using WLPP.