Sr1911 10mm question.

Delta elite mags are very different from standard colt mags. 10mm is longer and narrower than .45acp, so I seriously doubt it would work at all, let alone work well enough to use.

Ruger magazines are a different configuration externally and use a round follower. Haven't tried it but I suspect 10 mm ammo in a 45 mag 1st round might feed and fire but recoil will cause the rest of the rounds to pop/ bounce out of the magazine.

I have two 10mm 1911's and both feed perfectly with Wilson Combat 47D 8 round magazines. I own a dozen of them, plus a half dozen Tripp Cobra 9 round 10mm mags.

I load nine rounds in each type. I suspect the higher feed angle from .45 ACP mags even improves feeding.

The Ruger 10mm mags look similar to 9mm or 38 super mags with a rib running the full length of the body. Now this is Ruger mags don't know about Tripp,Wilson and others.

I won't say they CAN'T work but I wouldn't trust them. 10mm mags by every manufacturer I've seen look completely different from their .45 offerings.

http://joes1911magmania.net

Picked up some mags for my SR 1911 10mm from this outfit and they are well built and work flawlessly.
Good price, too.