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This is a first for me... I've shot THOUSANDS of rounds through both my XDm and my USP (both in .40) and have never had any issues with either, but just recently my USP seems to be occasionally jamming on the last round of the mag. I just bought another new mag for it a couple weeks ago and that was the first time it happened. At first I thought it was the new mag, but now it's starting to happen on others. So far I think it's been about 4 instances, two different mags, and a few different boxes of Blazer Brass.

No signs of any abnormal wear or anything on the feed ramp that I can see, and other than this one oddity, no other issues. When it DOES jam, the round ends up holding the slide back, and the tip of the bullet is stuck up against the bottom portion of the feed ramp. Anyone have any thoughts/suggestions?

Just my amateur 2¢

Are the mags being kept fully inserted by the latch? -or are they dropping back down a lot after the latch clicks?

As the slide/bolt grabs the back of the the fresh round to load it, it pushes it down and the nose tips up from the spring pressure and the follower tilting. A dead mag spring will cause that FTF, but I doubt that's your problem(new mag). I'm thinking that with a full/partial mag the spring pressure is high enough to tilt the rounds enough to feed, even with bolt barely engaging/not pushing down enough.

How old is it, how many rounds through it? It may be time to replace the recoil springs.

Yep, fully inserted and grabbing. Even topped off at 13+1 the mag only has about a 1-1.5mm gap around the grip base. As I was typing out my first post I was thinking the same thing (weak follower spring) but also thought better of it after the first instance came from a new mag. Not sure what to think at this point. I'll have to take a closer look at the followers on the mags, and perhaps do a few dry cycles while looking at everything real close to see if anything else pops out as being odd, but I'm not too hopeful that that will result in anything helpful.



Can't be much more than 7-8 months old (bought brand new at the time.) Unfortunately I don't keep very accurate records on rounds fired, but since it's my daily carry (XDm is my primary range toy) it's pretty low. Guestimate in the neighborhood of 1000 rounds.

Doubt this is of much use either, but I also don't suspect dirt/grime to be a player in the issue since I clean that gun at LEAST every range trip (and can't think of any where I've put more than 100 rounds through it betwen cleanings.)

Your low round count, and the pistol being dirty should have no effect. I have shot 10,000 through one of mine without cleaning. A USP doesn't have issues unless something is broken. If it continues, send it to HK.

Poor poor USP. Sorry, I love my USP and I'd never run Blazer through it.

On topic, I'd agree with checking the follower springs, but that shouldn't be an issue with new mags. Also agree with checking the recoil spring. Contacting HK might be a good idea either way.

I won't own anything that can't handle cheap/Blazer-esque ammo day in and day out. I figure that if it can handle that without a problem, then it should eat ANYthing. (Proven right so far on my XDm. USP is now to be determined...)

Any local places where one might find USP parts such as the recoil spring (and other parts for that matter?)

Could be a bad follower spring or maybe a bad follower tripping the slide catch early.

There are a few different things you could try, mag springs, recoil springs etc. But the point is, you shouldn't have to do ANYTHING to make the USP run like a top with ANY ammo. Just send it in. I have 6 different ones right now in different sizes and configurations, and must have had 15 of them over the years. I have never experienced a jam or failure of any kind in any of them. Some are going on 60,000 rounds.

I couldn't agree more. That reputation is 99% of the reason I went with an H&K in the first place. Unfortunately, I don't really have anything else for daily carry while the USP is out of service (and won't until tax refunds start showing up) so that'll have to hold for a bit, or I'll have to get lucky and figure it out =) (For the record, the XDm is just a BIT too much for me when it comes to daily carry, otherwise I'd just use that.)

Lol, you're saying your USP is small enough to carry daily but not the XDm? That's funny

Personally, I love my USP too much to run cheapy crap through it. I guess it depends on your budget and pride in your firearms.

There's a pretty major difference in the grip sizes (and even barrel length) that does indeed make the USP a lot easier to carry for me.

Pride has nothing to do with it. The HK is an 'uber' tool and as such, should eat any ammo thrown at it without even blinking. If I wanted a gun that needed 'good' ammo to operate, I'd have picked up a crappy gun that does have issue with anything but the 'good' stuff. =)

In any case, a little bit of a development on this after a trip to the range last night. I went ahead and numbered all four mags (should've done that ages ago, but I digress) and ran them through a few tests. In the first round, I ran five rounds through each mag. Magazine 3 jammed on the last round. It seems to be pushing the round out of the mag and a bit to the right, snagging the bullet on the edge of the feed ramp.

Pics:




I then did the same, but ran the mags in reverse order, no jams. Downloaded to 3 rounds per mag, and did the same thing again in both orders, no jams.

Finally, I loaded 6 rounds into each, and got no jams again.

So to say the least, it's not terribly easy to reproduce the issue consistently. I do have some reason to believe that I may be working through a bad batch of my Blazer stash though. Right after the testing, I set the HK aside to cool down before packing up, and ran the rest of my ammo (10 rounds) through my XDm, trying for a little accuracy. What do ya know... 10th/final round jammed. The XDm, however, didn't just position the round neatly between the feed ramp and the slide like the HK did. It instead damn near bent the casing in half with the round still in it. That was fun to clear.

In any case, yeah, I'm gonna reserve judement until I can do some more testing since I find it VERY odd that the XDm jammed as well (that gun simply NEVER jams.)

I've run probably 1000rnds of blazer brass through my USPc .40 without any issues, plus 500rnds of BVAC reloads, and prolly more than a 1000rnds of WWB.

Just one look at that feed ramp, tells the whole story...
I'm surprised it doesn't happen more often than it does.
What's up with the bottle neck design?
Grind baby grind...polish, polish, polish.

That looks better than my ramp at the moment.