HK USP magazine ejection issue?

General Firearms Handguns - Semi Auto
1

I’m trying to decide if this is normal or not, but when trying to eject an empty magazine from my full size USP with the slide locked back the magazine gets hung up in the magwell and fails to drop free.

When ejecting a mag with the slide forward and the hammer down, the mag drops free fine, and is actually propelled out of the gun via spring pressure. However, when the hammer is cocked the mag will fail to drop free.

So it seems that whenever the mainspring is under pressure from either having the hammer cocked, or the slide locked back, it flexes slightly into the mag well causing the magazine to bind and keeping it from dropping free.

My question to you is whether or not this is normal, or if I need to fix something in order to get my mags to drop free under all conditions?

Many thanks! :neo:

2

try having the magazine removed and locking the slide back, then inserting the magazine and seeing if the magazine release lets it dump free.

How does the magazine follower and slide stop look?

3

The mag still binds when inserted with the slide locked back. The main spring is putting forward pressure on the mag body whenever the hammer is back.

The mags are new HK 15 rounders and the slide stop appears to be fine.

4

What model is the USP? Have you inspected the magazine(s) housing? I’m assuming you’ve tried various magazines. Can you pull the mag out easily with your fingers or do you have to use a little force to take it out?

5

It’s a USP 9 full size. I’ve used all four of my mags, and it’s the same story, so I’m ruling out the problem as a mag defect. I can strip the mags out by hand easily, and that is how I’ve been conducting reloads lately. I would much rather they fell out on their own though.

6

Have you disassembled and inspected the magazine release? Maybe some dirt debris is causing it to bind. I’d give that a shot. Its easy to do, just drift out the roll pin holding the magazine release in place. Clean and see if that helps.

7

I really doubt that it has anything to do with the mag release.

I can see the main spring flex into the mag well and contact the magazine, which is causing enough friction to keep the mag from dropping free. So basically I need to know if the main spring protruding into the mag well is normal or not.

8

mine falls freely no matter where the slide is…forward or locked back…full mag or empty mag.

9

Upon further research, it appears that I may have a bent hammer strut, or a main spring that is too long.

http://www.hkpro.com/forum/hk-handgun-talk/137571-16-round-hk-usp-40s-w-mags-dont-fall-free.html

I needed to make an order from HKparts anyway…

10

Well I pulled the main spring out, and discovered that the hammer strut was trying its best to look like a rainbow.

I may try to straighten it for now, but I’ll be replacing it soon.

11

Glad you worked out your issue Tuck…Check your lockout device as racking the slide with it in the lock position is what likely bent your hammer strut.

12

I’ve got the USP detail stripped and parts on the way from HKparts.net.

I think I will be having my favorite 'smith put it back together for me though…

13

Glad to see you realize shit happens; even to one of the best pistols out there. Too many times someone has a hiccup with a good weapon and then decides to simply get rid of it. The USP’s have run flawlessly for me and I know they are held in high regard by those that have been there, done that.

14

This is my first HK product, and it won’t be my last. Seeing as the gun used and is 12 years old I was expecting some minor issues to pop up. It’s not a big deal and I’ll have it up and running soon.

I also want to give a shout out to Adam at HKparts.net for answering all my questions and getting me squared away.