Slide Releases When Mag Inserted

[George757]

With the slide locked open, if I insert a (Nighthawk Custom) mag and hit the base pad hard, the slide will release (and chamber a round). My wilson mag doesn't do this. What's up?

[Spindly61]

Does this happen with a loaded magazine? Do you have an extended slide stop installed?
Inertia from slapping a magazine in hard can lead to this happening. The angle of the magazine in the pistol is angled towards the muzzle. With a hard magazine insertion, the mass of the slide allows it to stay where it is with the frame moving up and forward. This sudden movement takes pressure off the slide stop due to recoil spring compression. I would imagine this is what is happening to you.
If this hard of an insertion is needed, I would look into making the seating of a magazine easier. Smoothing out and polishing the underside of the magazine catch is one area I would look at. Brownells also makes a reduced power spring for the magazine catch/release.Hope this helps.

[George757]

This happens during a 'reload', and it's an extended slide stop. I was wondering if it was a magazine issue, or gun issue. The gun itself has about 1200 rds thru it, using the same mags (Nighthawk/Wilson), and this hadn't occurred previously.
Thanks.

[Spindly61]

If you have an original slide stop I would try putting it back on the pistol and trying that.
Heavier mass on the extended slide stop. That would narrow it down some.

[John]

First of all, make sure that when you lock the slide back manually the slide stop goes all the way up in its cut in the slide. Second, check that the slide stop goes all the way up when the slide is stopped after firing the last round. Most probably the slide stop is not allowed to go all the way up in both cases. Let us know.

[George757]

John,
When manually locking the slide back on an empty mag, the slide stop is fully engaged into the slide. I won't have a chance to get to the range for a few days, but I'll check the 'last round' engagement asap. Thanks.

[John]

So if you insert an empty mag and rack the slide, the slide stop goes all the way up, right? Then the most probably culprit is the heavy, extended slide stop. If you have the original slide stop that came with the pistol, give it a shot.