Take this with a grain of salt, since I'm using a compact large frame.
I ordered the 13rd. small frame compact magazine and add 1/8" plywood shim to the back exterior of the magazine (Hey, I was lazy and used epoxy, I'll do something fancy later). The magazine's I got from CDNN are exactly the same width & height, just not deep enough without the shim. This works with both ball and hollow point, loaded long or short (UMC Remington ball feeds, and S&B hollow points feed).
The alternative solution I tried was using a modified STI type internal spacer at the back of the compact large frame magazine with a small frame follower. This works also, but will still nose dive with some of the hollow points.
Before the doing the modded magazines I could not load/feed more than 10 rounds through my magazines, and hollow points were a disaster. Ammo I'm using is all new/non-reloaded (S&B ball, UMC ball, S&B hp, Gold Dot hp, Winchester white box ball, Federal ball).
Again that's my experience with the compact large frame.
This post has been edited by mwalls: 09 February 2010 - 02:52 PM