Home Forums Hunting & Shooting Handguns 10mm Auto and AA#9, I think I have a winner here, intersting chrono results

It sounds like Safariman is working up carefully, so I don't see any problems with what he is doing. If I decided to hunt deer or pigs with a 10mm I'd likely take a similar approach. Echoing what Doc said, small changes in components can change pressures in a hurry with small high pressure cartridges.

Caveats I'd include would be:

1. AA powders were at one time notorious for lot to lot variation, so changing powder lots means starting over with load development. They are now said to be better, but I'd still be likely to buy a keg at a time.

2. in a safe place, cycle loaded rounds through the action, to confirm that bullets are not setting back in feeding, which can greatly raise pressures. I use an expander plug that is only .392" diameter, so basically it only bells the case mouth, allowing tightest possible bullet fit.

3. The unlocking of a 1911 is highly influenced by the radius on the firing pin stop. For adventurous loads I'd probably order a stop with a small radius, which delays unlocking.

4. The older Hornady manual was pretty warm on 10mm loads.



the load above was 13 gr of AA#7 (Hornady's max was 13.7), under a 155 Sierra, and ran 1425 fps. I notice now they have cut the max load by a full grain.

4. Although I probably wouldn't use it for defensive use, the ramped barrel on a Kimber gives more case support.

*****

I personally was happy with 155's at 1325 fps, which beats most modern factory .357's.