I've tested 200gr +P ProLoad Tactical Grade, 185gr Winchester Silvertip, 165gr Federal Personal Defense HydraShok, 185gr +P Georgia Arms and 185gr +P Remington Golden Saber with a .45 ACP Glock 30 and found that all of these bullets (except Remington Golden Saber) exhibit inconsistent or nonexistent expansion performance when fired through four layers of heavy denim cloth and into standard ordnance gelatin. Of all the loads I've tested so far I'd rate the 185gr +P Remington Golden Saber to be the best "all season" cartridge for this pistol because penetration and expansion performance are pretty consistent in both bare and denim covered gelatin. It ain't perfect (all bullets I tested expanded after passing through denim cloth, but a few shed their jacket and the lead core penetrated 18+ inches), although it's the best I've tested so far, in my opinion. The drawback is recoil and muzzle flip. ProLoad 200gr +P is a superb "summer-only load" where light clothing is anticipated. Georgia Arms 185gr +P is a good "winter-only load." Both the Silvertip and Personal Defense loads failed to expand after passing through denim cloth and all the bullets I tested penetrated 18+ inches.
Given the performance I've observed, I suggest you consider the .40 S&W G27 over the .45 ACP G30, if you want to go big bore. As for .357 SIG, the last performance data I reviewed showed the 125gr JHPs to penetrate very deeply after passing through heavy clothing, more deeply than 9mm 147gr subsonic. All the bullets expanded, but they didn't expand to a large enough diameter to quickly slow and stop the bullet.
If you're concerned about overpenetration, I believe .40 S&W is the best choice (at this point in time) when considering which mini-Glock to choose. It has a wide range of bullet weights that are driven at sufficient velocity to ensure more reliable expansion performance than .45 ACP and more optimal penetration than both .45 ACP and .357 SIG. This is bound to change in the future as .357 SIG ammo is refined.
I've not researched the ability to safely and successfully convert the G27 to .357 SIG or the ability to convert the G33 to .40 S&W. This might be something else to consider.
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/s/ Shawn Dodson
Firearms Tactical Institute
http://www.firearmstactical.com
[This message has been edited by Shawn Dodson (edited December 09, 1999).]
[This message has been edited by Shawn Dodson (edited December 09, 1999).]