Semi-auto nose damage

[Black Jaque Janaviac]

I am trying to reload for a small 9mm. I does OK with reloads but i have noticed the nose of the bullets (Lee 356-125-2R) gets a dent when it cycles. It happens when the magazine is full and only when I fire it. I can't get it to repeat just by hand cylcing.

I figured out the dynamics, I just don't know what to do about it. The slide starts to move forward pushing the top round out. There is enough friction between the top two cartridges that the second round begins to slide forward also. This places the nose of the next cartridge right at the bottom edge of the feed ramp. When I fire the gun the barrel and feed ramp move back with enough force that the edge of the feed ramp gouges the nose of the bullet. That is why I can't get it to do this with a dummy round and hand cycling.

Is this from too strong a spring in the magazine?

[Handloader109]

Does it happen with all the magazines? I have a RIA that really doesn't like 9 rounds in the full magazine and will sometimes do this. Download to 8 and no issue at all. Only some aftermarket mags do it.
Guns do strange stuff.. I have a new Kimber Micro 9 and if remove a full mag it drops top round out almost 100% of the time. Hasn't hickupped on shooting, it just is starting to remove top round early I guess.
I wouldn't have noted it, but found some folks on Kimber forum complaining about this. I don't see it is an issue. Gun runs fine.

[Black Jaque Janaviac]

Yep. I have the µ-9 too. It did the same thing; dropping a loose round when I removed a full magazine. However it doesn't do that anymore. It still moves the round forward, just not far enough to pop out.

This is with factory magazines, and I can't find any aftermarket stuff for the µ-9.

I would say that it is not a problem except that after the snow melts, I find all these bullets with a gouge on the nose. Then I will fire one round, hand-eject the next, and yep there's that same gouge. It can't be good for accuracy. Not to mention - if the force is enough to gouge the nose of the bullet - is it enough to push the bullet back in the case and deep-seat it, causing pressure problems?

[Dan Cash]

Unless you are trying for 200 meter rams with your little 9mm, don't worry about it. Dinged projectile noses have little affect on accuracy.

[dkf]

It is from the gun being a semi auto. Good luck trying to get rid of it.

[Black Jaque Janaviac]

It is from the gun being a semi auto. Good luck trying to get rid of it.

I see.

So setting the bullet back is not really a concern?

[rintinglen]

Bullet set back IS a major concern: a dent in the bullet nose is not.

Driving the bullet deeper into the case reduces the room for the powder and raises pressure. In a relatively high pressure (30,000+ psi), small case capacity round like the 9mm, this can raise pressures to the point where the case lets go, shattering grip panels, blowing magazines apart and peppering palms with splinters.

Denting the boolit has virtually no effect on anything relevant to a 9 mm projectile's purpose. 100 plus years ago Dr. Mann conclusively demonstrated damage to the nose of the bullet had very little impact on grouping.

[dkf]

I see.

So setting the bullet back is not really a concern?

Yeah if it is significant setback. The bullet setting back .010" or so is no big deal. But it should not setback that far after 2 or 3 chamberings. The next question would be why are chambering the same round so often, especially with a cast bullet.

[Black Jaque Janaviac]

Yeah if it is significant setback. The bullet setting back .010" or so is no big deal. But it should not setback that far after 2 or 3 chamberings. The next question would be why are chambering the same round so often, especially with a cast bullet.

OK. So if I just shoot the bullets right away the setback won't be enough to matter. But if I save the round and cycle it through the action again and again it could become a problem. I just thought that if the feed ramp is hitting the bullet hard enough to dent or gouge it - it could be hard enough to set it back.

[lar45]

I would start with measureing a round before and after cycling. Then cycle the same round again and again, measureing each time. Then you will know if setback is happening or not.
If it is, then something needs to change.

[35remington]

It is only a problem if you are firing the round above it repeatedly and replacing the round to first in the magazine repeatedly.

That seems unlikely.

[RED BEAR]

You should crimp so setback doesn't happen.

[dkf]

OK. So if I just shoot the bullets right away the setback won't be enough to matter. But if I save the round and cycle it through the action again and again it could become a problem. I just thought that if the feed ramp is hitting the bullet hard enough to dent or gouge it - it could be hard enough to set it back.

You can make some dummy rounds and chamber them each one by one by "slingshotting" the slide. Measure COAL after each chambering. See how much the setback is. If there is too much you may need more case tension. Taper crimp does very little to hold the bullet in place. Roll crimping on a cartridge that headspaces off the case mouth is not ideal. Semi auto pistol cartridges are taper crimped for a reason.

The bullet contacting the feed ramp on a semi is unavoidable. All the semi auto pistols and rifles I have mark the nose of the bullet during each chambering.

[Black Jaque Janaviac]

You can make some dummy rounds and chamber them each one by one by "slingshotting" the slide.

Nope. Won't work. I don't know if anyone can slingshot a semiauto as fast as its own recoil. It takes the recoil of firing a round in order to hit the nose hard enough. It's kinda weird - it will happen on the third shot if I load a full magazine +1. I put in a full mag, slingshot the action to chamber a round, eject the mag, top it off, and push the mag back in place. I now have one round in the chamber, and the cartridge directly underneath the slide is rearward in the magazine, because it was loaded into the mag by hand. Then I fire the gun, the slide goes back and forth. On the forward stroke, the slide pushed round #2 into the chamber, the friction between cartridges #2 and #3 is enough that #3 round is pushed forward against the very bottom of the ramp. When round #2 is fired, the barrel recoils with enough force that the ramp smashes the bullet nose. The same thing might happen to #4 - but after that the magazine spring doesn't exert enough force to cause the cartidges to push the lower ones forward.

[onelight]

Can you post a picture so we see it ?

[Kenstone]

I am trying to reload for a small 9mm. I does OK with reloads but i have noticed the nose of the bullets (Lee 356-125-2R) gets a dent when it cycles. It happens when the magazine is full and only when I fire it. I can't get it to repeat just by hand cylcing.

I figured out the dynamics, I just don't know what to do about it. The slide starts to move forward pushing the top round out. There is enough friction between the top two cartridges that the second round begins to slide forward also. This places the nose of the next cartridge right at the bottom edge of the feed ramp. When I fire the gun the barrel and feed ramp move back with enough force that the edge of the feed ramp gouges the nose of the bullet. That is why I can't get it to do this with a dummy round and hand cycling.

Is this from too strong a spring in the magazine?
A couple of things
1) The mag top/front cut-out may be too deep allowing the 2nd bullet (round) nose to be pushed forward, over the opening edge, and into contact with the feed ramp.
Some gun makers use the same mag profile stamping for both 9mm and 40SW, and just bend the mag lips closer together for 9mm and have a deeper front cut out.
2) The gun mag may have been designed around the use of Hollow Point (blunt nosed) bullets and the 2nd round in the mag would contact the front of the mag and not move out into the feed ramp.

Either condition could be rectified by changing to a different bullet profile, no a cheap fix if you are casting your own Lee 356-125-2r bullets [smilie=b:
I'm not sure any aftermarket mag would remedy your problems but asking your question in a gun specific forum might lead you to a fix.
good luck,
;)

[dkf]

Nope. Won't work. I don't know if anyone can slingshot a semiauto as fast as its own recoil. It takes the recoil of firing a round in order to hit the nose hard enough. It's kinda weird - it will happen on the third shot if I load a full magazine +1. I put in a full mag, slingshot the action to chamber a round, eject the mag, top it off, and push the mag back in place. I now have one round in the chamber, and the cartridge directly underneath the slide is rearward in the magazine, because it was loaded into the mag by hand. Then I fire the gun, the slide goes back and forth. On the forward stroke, the slide pushed round #2 into the chamber, the friction between cartridges #2 and #3 is enough that #3 round is pushed forward against the very bottom of the ramp. When round #2 is fired, the barrel recoils with enough force that the ramp smashes the bullet nose. The same thing might happen to #4 - but after that the magazine spring doesn't exert enough force to cause the cartidges to push the lower ones forward.

The whole purpose of what I mentioned is test for bullet setback. That is it.

What you describe does not sound abnormal and I would bet is how that particular gun is going to operate. With jacketed ammo (which most semis were designed to use) you would likely never see a mark on the bullet. Rounds shifting around in the mag during gun operation is pretty normal.

[Black Jaque Janaviac]

https://farm1.staticflickr.com/825/41745718111_20c040c31d_z.jpg (https://flic.kr/p/26AVHAx)DSC01616 (https://flic.kr/p/26AVHAx) by frozenfrizzen (https://www.flickr.com/photos/40087717@N03/), on Flickr
here are some bullets I recovered from the snow last year. I'll see if I can post some unfired bullets, ie cartridges where I fired a round, then ejected the next round.

[onelight]

Does it do that with factory loads? If so I would contact the manufacturer that is unacceptable in my opinion.

[dkf]

The picture helps a lot. That is not the normal location on the bullet you usually see the divot from chambering a round. Those are directly on the point of the nose and deep too boot. Much worse that I was thinking from your description. What gun is it?

[RED BEAR]

I have to agree that is worse than i was thinking to. You can't tell where it is hitting just by cycling the action with dummy rounds. I am amazed that these feed at all.

[str8wal]

Looks like you may need to work on the feed ramp.

[onelight]

If the manufacturer is still in business and the gun has not been modified in a fashion that could cause your problem I would contact them that kind of blow on the nose of the bullet could cause dangerous set back as others have pointed out personally I would not shoot until it is corrected.
Many manufacturers will correct something dangerous even when out of warranty.

[JBinMN]

IMO... and a "Ditto" for some others...

Contact the mnfr of the firearm about this before anything else is done.

[Black Jaque Janaviac]

https://farm8.staticflickr.com/7881/33606622748_f561f2ebfa_z.jpg (https://flic.kr/p/TcGJ79)20190327_214630 (https://flic.kr/p/TcGJ79) by frozenfrizzen (https://www.flickr.com/photos/40087717@N03/), on Flickr

Here are some bullets that were not fired - just to prove that the dents occurred before being fired from the barrel.

It is difficult to measure OAL because the lead upset and there's a small bur on the edge of the gouge. But it appears there was no measureable setback in this one instance. Would the fact that these are reloads void a warranty?

[onelight]

https://farm8.staticflickr.com/7881/33606622748_f561f2ebfa_z.jpg (https://flic.kr/p/TcGJ79)20190327_214630 (https://flic.kr/p/TcGJ79) by frozenfrizzen (https://www.flickr.com/photos/40087717@N03/), on Flickr

Here are some bullets that were not fired - just to prove that the dents occurred before being fired from the barrel.

It is difficult to measure OAL because the lead upset and there's a small bur on the edge of the gouge. But it appears there was no measureable setback in this one instance. Would the fact that these are reloads void a warranty?
Does it do that with factory loads ? Show them some of those..

[Black Jaque Janaviac]

I guess I'll have go buy a box for demonstration purposes. Thanks guys.

[Dusty Bannister]

What is the micrometer reading of your case mouth with the plated and the powder coated rounds, after seating and crimping?

[marshall623]

Looks like a gun issue the manufacturer needs to make right from the red boolit pic

Sent from my SM-G930V using Tapatalk

[Black Jaque Janaviac]

I've got a box of factory ammo now. Just have to find the time to sneak away and pop a few rounds off to see what kind of damage to the nose is observable.

The gun is a Kimber Micro 9 (µ-9). The cases are all Winchester headstamps (some are 9mm some 9MM if that is of any concern). The OAL of the cartridges with the red powder-coated bullets was 1.09" before loading into the magazine.

In the first photos, the cast bullets are the same as the powder coated - just pan-lubed. The copper bullets are Winchester white-box FMJs so they are not plated, but jacketed so I guess, yes, it does do this with factory loads. The fired bullets were recovered when the snow melted. Since they are fired - one could argue that the dent is occurring at some point after the bullet has left the barrel. However, the loaded cartridges, prove the damage occurs during action cycling.

I will be firing some more factory loads, and ejecting unfired cartridges. Then I will box it up and send it back to Kimber. They've been great so far.

[onelight]

I hope they get it lined out.
Kimber makes some really nice guns.
Let us know the outcome.

[Walks]

Get your hands on another magazine.

Most feeding problems can be traced to usually 1 of 3 things.
1) ammo, try factory RN, if It's a European pistol, try Fiocchi.
2) The gun, polish the feed ramp
3) The most common, the magazine. I have 4-5 1911 WW2 mags that will feed hardball ONLY. Get another one. Isn't it cheaper then beating your brains out half a dozen different ways?

Sounds like the mag to me.

[Black Jaque Janaviac]

Get your hands on another magazine.

Most feeding problems can be traced to usually 1 of 3 things.
1) ammo, try factory RN, if It's a European pistol, try Fiocchi.
2) The gun, polish the feed ramp
3) The most common, the magazine. I have 4-5 1911 WW2 mags that will feed hardball ONLY. Get another one. Isn't it cheaper then beating your brains out half a dozen different ways?

Sounds like the mag to me.

Kimbers come with only one magazine. I did buy a second magazine. I will check to see if both magazines do the same thing. I cannot find any aftermarket magazines that fit Kimber Micro 9. So I think I'm stuck with the same brand magazine - Sig 938 magazines supposedly can fit but need some modification.

[Black Jaque Janaviac]

OK. The definitive test. Yes it does this with factory ammo. Federal 115gr. FMJ aluminum case. That way there's no mistaking the picture as a reload.

In the first picture the Winchester white box had the dent, but didn't jam. The Federals jam.

Here is a picture of one of the rounds that jammed - I did not fire it so it would be plain that this damage is not done when the bullet impacts the target or berm. I'll be boxing the gun up this week and back to New York it goes.
https://farm8.staticflickr.com/7839/46586890095_a42b839e5f_z.jpg (https://flic.kr/p/2dYHZn2)[url=https://flic.kr/p/2dYHZn2]