LC9 Bent cases

Flametamer · Jan 16, 2015

While at the range earlier today, I noticed for the first time, that 80-90% of the spent brass from my LC9 is dented. All of the dented brass looks the same although there is some variation in how deep the dent/crease goes toward the center of the case.

I was shooting ZQI 123 grain for the first time and had a couple of other minor issues like brass flakes in the works and two FTFeed out of 150 rounds. The FTF and flakes are not so troubling given what I paid for the ZQI, but the bent cases are intriguing. Anyone seen this before and/or have an idea what may be causing it?

Long1MD · Jan 16, 2015

It's the ammo. Have an LC9 and no problems but never ran ZQI through it. I have seen some posts about ZQI 223/556 not holding up.

zoostation · Jan 16, 2015

Usually you get dents like that when the case is ejecting too slowly and getting dinged before it can completely clear the ejection port. Common causes could be a worn or loose ejector, an extractor issue (worn, too weak, too strong) or a worn recoil spring. I would also suggest getting behind the ejector and scrubbing it out real good to make sure there isn't some small debris caught back there buggering things up. Could be this particular ammo causing the gun to cycle out of time too, but I kind of doubt it. Not really familiar with that ammo though. Of course, any time you see high pressure cases like 9mm deforming the safest thing to do is check with a gunsmith to make sure there's nothing really bad brewing.

I have an LC9 with about 400 rounds through it and have not seen this problem. Be interesting to see if this happens with other ammo.

traveller · Jan 16, 2015

There was an entire thread about ZQI ammo. I believe it was called 'ZQI overpressure ammo'.

Some of them seem to be loade a bit hot +/- their brass being a bit soft. Combine that with a unsupported chamber and you get bulging cases.

BradMacc82 · Jan 16, 2015

Zoo, I normally would agree with you. But after trying some of the ZQI offerings, I'm going to lean towards the ammo being a bit 'hot' for that particular firearm.

Like some of S&B's offerings, they definitely seem to be full power loadings.

mopar92 · Jan 16, 2015

Theyre NATO spec ammo. Is the firearm rated for NATO or +p/+p+ loads?

zoostation · Jan 17, 2015

BradMacc82 said:
Zoo, I normally would agree with you. But after trying some of the ZQI offerings, I'm going to lean towards the ammo being a bit 'hot' for that particular firearm.

Like some of S&B's offerings, they definitely seem to be full power loadings.

Yes, I did a little research on them after I posted. Looks like they're imported from Europe. And they do tend to load 9mm hot over there.

traveller · Jan 17, 2015

zoostation said:
Yes, I did a little research on them after I posted. Looks like they're imported from Europe. And they do tend to load 9mm hot over there.

Turkish SMG ammo.

outrider58 · Jan 17, 2015

I believe there was a previous thread about ZQI ammo (and problems with it). I think in 9mm, though not sure on the caliber.

Flametamer · Jan 17, 2015

Thanks for all the replies. The LC9 manual states that it can shoot +P, but that one should not feed it a steady diet of +P. Given that and in light of what I've learned about the ZQI loads, I won't be buying any more ZQI for this gun.

Flametamer · Jan 19, 2015

I went to the range to play a bit on this issue. While I've shot this gun a lot, I never bothered to look closely at the brass since it gets mixed up with other shooters' brass on the ground here. Hence, I really can't surmise as to whether this has occurred with this gun before.

I took 8 different loads and fired three round of each. Marked each case with a sharpie to show the top of the case and verified that the mark was facing UP as each round was chambered. Caught and inspected each case as it ejected (that was fun). Took notes and summarized in the PDF file attached. Also have attached pictures of one selected cases below.

Based on the sharpie marks, the deformation/scratching is occurring at about the 4 O'clock position on the case (looking down the barrel from the breech). None of these rounds suffered the deformation that the ZQI loads did. There were some dents, and almost every case had triangular shaped scratched area at 4 O'clock. Photos show the worst of the dents in these loads, as well as cases that were scratched but not dented. No failures at all; everything went bang when it was supposed to.

I was able to replicate the scratches with a undamaged empty case in the gun after I took a look at what happened. I'm not sure whether I have a "problem" or not. This is the extractor side, and I cleaned the extractor before going out today (it was hardly dirty). I'm pretty anal about cleaning my guns, so I don't think the problem was a dirty extractor. This gun really throws the brass, could it be that the spring is too strong? I'd appreciate any thoughts you may have.

BradMacc82 · Jan 19, 2015

How many total rounds thru that LC9?? Roughly.

lee2 · Jan 19, 2015

does it fire and function fine?
then no problem.

Flametamer · Jan 19, 2015

Probably 1100 rounds to date.

zoostation · Jan 20, 2015

Flametamer said:
Probably 1100 rounds to date.

Might be time to consider a replacement recoil spring. Sounds like maybe you're seeing the beginnings of a fatigued spring, and the very hot ammo accentuated it. In any case it might be time to change it out, even just for preventative maintenance. Dual springs tend to wear faster than single ones and often get weak well before 1500-2000 rounds.

BradMacc82 · Jan 20, 2015

I'll second that, also take a look at the top of the barrel hood and see if there's any type of burr or raised material.

Flametamer · Jan 20, 2015

Replacement spring set on order. As I understand it, factory springs I ordered are 16 lb. I also ordered a set of the 20 lb. springs and SS guide rod from Galloway Precision. Looking forward to comparing the two spring forces (assuming this solves my issue).

Barrel hood looks good, no noticeable burr or extra material.

Thanks for all your input!

Flametamer · Jan 21, 2015

I just can't stand not understanding what's going on (it's an engineer thing). I just couldn't see what the cases were striking that would cause the scratches and dents. This is mechanical damage, so there simply had to be a point of impact... So I took to looking at the gun a bit more closely this morning.

I found a very faint brass track or band across the port on the slide where the rounds are sometimes 'dragging' on ejection. That was interesting, so I looked harder and noticed a very small nick in both the edge of the slide and on the rail immediately below it. Interestingly, both matched up with the leading edge of the case, and are located in the correct spot for the marks on the cases. At first I thought this was merely worn-away finish, similar to a couple of other spots on every gun I own. When I dragged my fingernail and a dental pick across the nicks, I note a barely perceptible roughness, and even got my nail to 'catch' on it one time.

Ah-ha; I think I know what is going on! While I'm waiting for the new springs to arrive, I think I'll do a bit of careful polishing. Might as well do a bit of lapping like that shown on the YouTube LC9 LAPPING video while I've got the tools out.

.

LC9 Bent cases

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