XDM Slide did not lock back

[titanxdm]

Today I bought a box of 100 Walmart Winchester 165gr FMJ.

Went to the range and let her rip.

For Christmas, Santa brought me a lasermax guide rod. This replaces the guide rod spring. I did put 65 rnds through it after Christmas to test the rod and spring with no problems.

Today though, after about 80 or so rounds, the slide did not lock back after the mag was empty. This happened twice in a row. Then I loaded up the remaining bullets and counted down watching the slide and it locked back.

I have shot this gun many times, and never had this happen. Could the spring have an affect on this. I think it is supposed to be the same weight as the OEM spring (not sure).

My other goal was to see if the laser still hit the target after a bunch of rounds, without wiping the lens...It still looked good after 100.

Thoughts on the slide not locking back?

[harold63]

Put an empty mag in it and see if will lock back when you hand rack it a few times. If it locks back everytime, it may be that it isn't being blown all the way to the rear when shooting. If it doesn't lock back everytime you hand rack it, you may need to trim the edges of the mag follower (trim as in scrape the edges just a tiny bit so the follower will come all the way to the top). The plastic followers can swell a little if you get solvents on them and don't wipe them off, causing the edges to drag.

[titanxdm]

Thanks, I will check the follower.

I suppose it could have been dirty (used the same mag the whole time) and that could cause it to drag?

I cleaned her good and she locks back. But I did not touch the mag, and normally don't.

I think I am starting to see where my problem might be.

[harold63]

Thanks, I will check the follower.

I suppose it could have been dirty (used the same mag the whole time) and that could cause it to drag?

I cleaned her good and she locks back. But I did not touch the mag, and normally don't.

I think I am starting to see where my problem might be.

When the slide won't lock back on the last round, it is where I start. Some burnt gunpowder could be in there, sure, but mags will work dirty in most cases. Still, good idea to keep the mags clean, as well as the pistol.

A lot of mag followers have molding flaps at the bottom of the follower (where the spring goes in). These little "flaps or burrs" do not need to be there. When hit with a solvent, these burrs expand and will not let the follower come all the way to the top and manipulate the slide stop. Any residue in there will make the problem worse. A fingernail file just on the bottom edges of the follower or lightly scrape the edges with a utility knife or razor blade, but try cleaning before trimming. It may be all that is wrong.

Edit: if that fails, make sure the slide is lubed well where it mates with the frame. Try shooting with a stiffer wrist and grip on the last round. If the ammo you use is fairly soft, it may not push the slide all the way to the rear, but it can still eject the empty case. A stiff wrist will help with this until the new spring comes in some.

[RXM]

Make sure that your grip is not causing the issue. On the XDM, the slide release/catch is right near where I place my right thumb and I've had issues with the slide not locking to the rear on the last round.

[harold63]

Make sure that your grip is not causing the issue. On the XDM, the slide release/catch is right near where I place my right thumb and I've had issues with the slide not locking to the rear on the last round.

Definitely this, as well.

[Ranger P229]

Is this your first time shooting winchester white box with that firearm?

My Sig 229 won't lock back with Win. cheap ammo. I have to switch my recoil spring from the factory 16lb, to a 13lb spring to get my gun to stay out of battery with that particular ammo.

That being said, it didn't happen after X ammount of rounds, it just happens anytime I feel like shooting that ammo.

[swack]

I had a similar issue with my XDM but it only happened when using steel cased ammo. Switched back to brass and it disappeared.

[rwb1500]

Do you have more than one mag? Try them all, it will help you isolate your problem.