USP not returning to battery

[bottlerocket]

So this is a middle-aged USP and I've been having issues with it. I reload my ammo and sporadically I have an issue with the pistol not returning to battery and the cartridge not going into the chamber all the way. I cannot figure out why. I even tried some factory (I think, unless I forgot to take the sticker off the box...) loads and had a similar issue so I'm starting to think its related to the firearm. Its not the magazine because I tried a brand new one and its still having the issue. Its not any specific round either, like near the beginning or end. Sometimes its the first, sometimes its somewhere in the middle. Its also not the same physical round ever time. Each time I have one fail to feed I dot it with a sharpie. Sometimes its the same, but other times its different.

I am using various brass (Federal, Remington, Winchester, Speer) with CCI primers, IMR800X and Barnes plated bullets. I don't want to completely rule out it being an issue with my handloads quite yet either. Any suggestions on what to look for? I had an issue with my extractor getting gunked up a couple years back but I checked it and its clean. I maintain this thing meticulously and have not seen any indication of mechanical failure. I'm not exactly sure of the round count on it. I know I've put at least 500 rounds through it and no telling how many the previous owner fired, but the gun looks brand new minus some holster wear.

Any help is greatly appreciated. Here is a pic of what its doing...

[bottlerocket]

Ok I just tried it with some Speed Gold Dot (I know for a fact those are not reloads) and it did it on the second round. Its not the reloads it seems...

[bulldog896]

I'd change out the recoil spring you might also look at the feed ramp and the chamber make sure there are no burrs or "dark spots" friction is usually somewhere to blame with a ftf might try giving th pistol a good douching with oil and try it without the gun in my hand it's harder to diagnose

[bottlerocket]

It gets oil plenty, not too much and not too little. After close inspection of the feed ramp I may have found the issue. Lets see if this pic comes out...

[bottlerocket]

The part by the red arrow might be the culprit. The blue arrow is just pointing to some dust

[Venix]

Should have bought a Glock.







































J/k I hope you get it fixed, Also love the keyboard

[bottlerocket]

Should have bought a Glock.

J/k I hope you get it fixed

I was waiting for that lol. I don't care so much that its broken, I am just glad I ruled out my reloads causing the problem. It was driving me crazy messing with the dies...

[CJ]

I've fixed a few USP's with this problem. I suggest you polish the ramp, and remove the knife from the ramp lip - a very slightly chamfer on the ramp/face transition and a smooth proper polish on the ramp itself should help remedy this problem. Do not make it transition to a sharp point though, you do need that flat portion on the ramp, just make the transition softer. Before you finish up, put a small piece of towel on the end of your power drill with some metal polish and polish the chamber well. Also, like mentioned before you might also want to look into a new main spring if the problem persists. Also, do a slight kiss crimp on your reloads in case you have excessive bell.

Also, in your first pic you have a case experiencing a partial chamber, what happens when you push your side by hand into battery?

[bottlerocket]

I've fixed a few USP's with this problem. I suggest you polish the ramp, and remove the knife from the ramp lip - a very slightly chamfer on the ramp/face transition and a smooth proper polish on the ramp itself should help remedy this problem. Do not make it transition to a sharp point though, you do need that flat portion on the ramp, just make the transition softer. Before you finish up, put a small piece of towel on the end of your power drill with some metal polish and polish the chamber well. Also, like mentioned before you might also want to look into a new main spring if the problem persists. Also, do a slight kiss crimp on your reloads in case you have excessive bell.

Also, in your first pic you have a case experiencing a partial chamber, what happens when you push your side by hand into battery?

Ok can you translate that first part about the ramp stuff for those of us not familiar with gunsmithing terms?

And I'll go try to get one stuck again and push on it.

[bottlerocket]

Got it to jam a couple of times. If I give it a good thump at the back of the slide with the palm of my hand it will go into battery

[CJ]

Got it to jam a couple of times. If I give it a good thump at the back of the slide with the palm of my hand it will go into battery

then a polish will fix this I'm sure.

You need to polish the ramp - I suggest starting with some 400 grit until you get the grain out of the metal, and then polish it to a mirror shine. If you look at your ramp, you will see it's carved into a flat steel blank, and the flat portion is visible just barely below the ramp. You want to keep that there. Your concern is to remove the sharp transition from the ramp to the barrel face (flat part under the ramp) If that is too sharp it can cause the soft metal of the copper jacket to hang up and jam.

[bottlerocket]

then a polish will fix this I'm sure.

You need to polish the ramp - I suggest starting with some 400 grit until you get the grain out of the metal, and then polish it to a mirror shine. If you look at your ramp, you will see it's carved into a flat steel blank, and the flat portion is visible just barely below the ramp. You want to keep that there. Your concern is to remove the sharp transition from the ramp to the barrel face (flat part under the ramp) If that is too sharp it can cause the soft metal of the copper jacket to hang up and jam.

Found the problem...

[CJ]

Found the problem...

That's odd, I don't see how that would cause a chambering issue. Possibly because it's bent in would cause an out of ordinary angle on chambering. Hard to troubleshoot stuff I can't see, hehe.

[bottlerocket]

Lol well thanks for the effort! Yea I finally got someone to answer on HKPro and they first noticed that the round wasnt going in at the right angle and said it must not be up in the extractor all the way and there ya have it

[CJ]

Lol well thanks for the effort! Yea I finally got someone to answer on HKPro and they first noticed that the round wasnt going in at the right angle and said it must not be up in the extractor all the way and there ya have it

Yes the first picture shows the angle problem. I initially thought it was stuck on the ramp, but I can see now that it's in the mouth of the chamber and the case head is too low.