A few yearts ago I was looking for extra magazines for my Astra Constable .32. The only place I could get them was TrippleK and I had to wait 120 days until they made a manufacturing run. No problem but when the new mags arrived, while they fit fine unloaded, on the range they would not lock in properly. After the first shot the mag would drop in the grip.

Turned out that the mag release catch hole in the mag was slightly misplaced. Half an hour with srewdriver to remove the grips to diagnose the issue and neelde files on the mags and the problem disspaeared.

Fast forward a few years. Three months ago I was burgled and a whole lot of mags stolen, including all my 9mm 1911 mags and three for my mid 90's Tanfoglio CZalike.

A few weeks ago I found someone in Kiwiland with 10 round 9mm 1911 mags for sale (they are very hard to come by here at present). Unfortunately they looked like some I bought a few years ago advertised as 10 round but only holding 9. The same seller also had 17 round Tanfoglio CZ75 mags.

Having leanrt my lesson earlier I ordered only 2 1911 mags and a single CZ75 to try out. All three arrived yesterday.
Now the good news is that all were Mec-Gar mags and the CZ one went right in like it should do (I even loaded in 17 empty cses to test fit it in my pistol.

When it came to the 1911 mags in hy Kimber Stainless Target II it was a different story. Even empty they were hard to seat properly. Loaded with empty cases I had to really slam them in. And when they did go home the mag catch was abominable. I could barely release it again.

10 minutes on each mag with needle files, exending the mag catch cutout upwards, fixed the problem. But how ofen do factory manufacured mags need such hand fitting? I had 10 mags for the Kimber stolen. One original 9 rounds, 6 Wilson Combat 10 round and the three previously mentioned ones. None required any filing to work out of the packet. Same with all of my .45 1911 round mags, both 7 and 8 rounders.

The three Browning Buckmark mags I imported here a while ago all worked as advertised as do all my rifle mags. Is having to hand fit normal for Mec-Gar mags or did I just strike two bad apples?

PS. I would have bought new Wilson Combat mags but they are not available here and permits to import are not being issued right now.

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View from down under

Hard to say. My layman's guess is it might be an instance of tolerance stacking. Normally it would work if one or the other component was at the edge of tolerance, but if both are at the edge of their tolerances, you end up with an incompatibility issue.

I have seen that issue in my 1911s. I have 3 types of welded-base 7-rounders for them, Colt factory, Metalform, and King's Gun Works. I have one mag, I think it's one of the Metalforms, that will insert in one, but not the other unless the mag catch is pressed at the same time. The 1911 with the issue has a hard chromed frame, so sometimes I wonder if the refinishing caused just enough of an increase in dimensions that it doesn't work so well with that one mag.

Just a thought from a non-gunsmith.