Cramming 18th round in a 17?

[fitz19d]

Noticed today after qual that I managed to stuff an 18th into one of my magazines. Was kinda wondering, as long as they fit, will they actually run just as reliably or will it degrade the magazine quickly or not feed right?

I remember back in the day bunch of times some brands 9mm would be 18 rounds when practically speaking they were really 17's or whatever. Just not sure how it works in reverse where I can cram more than advertised.

[hurley842002]

How hard or easy was it to seat the mag into the pistol with 18 in there? I noticed yesterday that a G27 mag with Pearce + extension was a pain with 10 in the mag, to the point the slide was difficult to cycle manually.

[fitz19d]

Just due to where I was at, at the time and trying to get out of there I didn't monkey with trying to load it. Just noticed on my 3rd mag I was short the 52nd round. It went in with some effort but not a ton with a maglula. Maybe I'll monkey with it, but just probably don't have any range time free anytime super soon to experiment.

For me the old px4 magazines and somewhat the TP9's were like that less than a couple mm clearance and trying to strip the top round into the gun was really hard so making them say 16+1 instead of true 17's or 18's. I want to say the 18th round I had would be loose enough to strip off given how easy it came out when I downloaded it and I wouldnt have crammed it in, in the first place if it had been as tight as those old beretta mags I experienced.

[Great-Kazoo]

getting the extra round can cause it to pop up in to the slide and not chamber when charging the slide. it can also prevent the mag from being seated correctly. So first round chambers second doesn't as mag is sitting low. YMMV. IF it's made to take 17 put 17 in.

[Wulf202]

That space is for inserting on a closed bolt or slide. Some guns may work fine but I don't run mine past capacity unless as a range toy

[Shooter45]

As others have said, that extra space is to ensure a magazine will fully seat on a closed slide (or bolt in regard to an AR). It may fit on certain pistols or rifles, but don't count on it working in all situations. Load the magazines to capacity, chamber a round, the top the magazine up to the best condition possible. Not worth risking a malfunction.