Here is a problem that one of them asked me to help fix.

Gun: Springfield Armory 1911A1
Mags: Shooting Star 8 round
Malfunction: When using Shooting Star 8 round  or Metalform 7 round mags, the final round somehows feeds into a straight up position and gets jammed in between the slide and breech. It is like a stovepipe but with a loaded round. Does not occur with factory 8 round SA or Wilson mags.

I have no idea what could cause that.

New one on me, I've been shooting 1911's for about 25 years now and I've never seen that.

I have a Springfield as well.

I had the same problem with some mags, the cause was a weak spring.

I have both Metalform and one Shooting Star. The shooting star works fine now but wouldn't activate the slide catch.

Both type of mags would cause the problem you described. I fixed the shooting star mag and trashed the metalform mags since they are a dime a dozen.

I like the metal form mags for the range, they are around $7 or 8 from Bushmaster for the stainless ones.

I had that exact problem last week at the range testing out my new Springfield PX9109L, but only with one of the stock mags. The other mag was fine and the two Wilson 47Ds I tested were also fine.

BTW, the thing fed Fiocchi 230gr. ball, Fed XM1911, and PMC Starfire 230gr. perfectly, but I had multiple problems with Speer 185gr. Gold Dot. They didn't seem to feed well. Perhaps the recoil spring is too light?