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Scandiacus
08-11-2016, 09:12 PM
First of all, apologies if this has been asked before, but 30 minutes of googling and forum searching didn't turn up any satisfying answers.

I'm new to centerfire rifle ownership in general, and AR ownership in particular. My first time out shooting my AR, I failed to fully seat the magazine and the first two rounds I tried loading didn't chamber fully and came out dented near the neck. The dents are only moderately deep, but both have a "seam" at the bottom that's sharp enough to catch a fingernail on. Both rounds still chamber without any hangups, but I wonder if this kind of damage is likely to bump the chamber pressure up dangerously high. Any word on whether these rounds are still safe to fire?

The rifle is chambered for 5.56 and both rounds are Winchester branded M855. Thanks for any advice.

First round:
https://i.imgur.com/PBt03sM.jpg

Second round:
https://i.imgur.com/glO44SH.jpg

dave7120
08-11-2016, 10:38 PM
ive fired dented rounds before with no problem. so id say your ok to do it.

Galeforcerm
08-12-2016, 01:24 AM
I've had dents like that on ammo fresh from the box, never had an issue firing it.

pkuptruck
08-12-2016, 05:31 AM
generally, "dents" are not an issue, or problem...

BUT..

looking at your pictures ( and not knowing light, angle, etc of said pictures..) the first one
just seems "dented".. so , good to go.

the second one looks SPLIT.. not just "creased". if it IS split.. toss it ( of if you reload.. pull bulled and powder.)

Pyzik
08-12-2016, 07:10 AM
generally, "dents" are not an issue, or problem...

BUT..

looking at your pictures ( and not knowing light, angle, etc of said pictures..) the first one
just seems "dented".. so , good to go.

the second one looks SPLIT.. not just "creased". if it IS split.. toss it ( of if you reload.. pull bulled and powder.)

I think in this case it's the lighting. I think you're seeing a scratch in the dent. I was wondering the same.

Shoot em. Worst case you split the cases and you won't be able to reload them.

Scandiacus
08-12-2016, 11:11 AM
I think in this case it's the lighting. I think you're seeing a scratch in the dent. I was wondering the same.

Shoot em. Worst case you split the cases and you won't be able to reload them.

Even in person it's hard to tell. The creases/splits on both are nearly identical when inspected under uniform lighting. Assuming the worst and that both are split, what's the worst that can typically happen if they're fired? Is there much risk of damage to the gun, or just split cartridges? I don't reload, so I'm not too worried about preserving the brass or other components.

intheburbs
08-12-2016, 12:37 PM
The chamber fully supports the cartridge in the area of the dents. When you squeeze the trigger, you're generating 55,000 PSI of pressure inside that case. The dents are insignificant compared to the other stresses on the case. Fire away.

If you're really that concerned about it, just toss them. You're talking about $1 worth of ammo in a rifle worth hundreds, or thousands, of dollars more.

gl08jk
08-14-2016, 01:00 AM
I have fired dented rounds before. Like others mentioned i would inspect them more for stress cracks in dents. If you are into reloading those casings in the future set them aside and inspect them carefully for splits or stress cracks from case expansion after firing. I have had reloaded cases split on certain types of dents, especially closer towards the neck. Other than that the way they look i would fire them and inspect results.

JimSig
08-14-2016, 09:46 AM
Measure your risks to benefits.

Benefit = shooting two rounds, price 0.5$ x 2 = $1

Risks = busting a barrel and probably a magazine and possible injuries. $150 for barrel, $10 for magazine, and no price is worth it for possible injury

Do the math dude

Scandiacus
08-14-2016, 03:41 PM
Thanks for the input everyone. From what I'm hearing I'm not too concerned about them damaging the gun, but given it's only $0.80 worth of ammo, I'll likely just disable the rounds and keep them around as knickknacks. They've been sitting on my desk ever since they were dented a couple months ago, and I've gotten used to having them there.

JasonJ
08-18-2016, 11:36 AM
Thanks for the input everyone. From what I'm hearing I'm not too concerned about them damaging the gun, but given it's only $0.80 worth of ammo, I'll likely just disable the rounds and keep them around as knickknacks. They've been sitting on my desk ever since they were dented a couple months ago, and I've gotten used to having them there.

This is the smart way to go about it... not worth it. Pull the bullets, empty the powder and remove the primer, stick the bullet back in and keep them as desk decoration. Not worth the risk for, as you say, 80 cents in ammo.

nmuskier
08-18-2016, 04:27 PM
Good gravy, that's barely a love tap. Barely worth mentioning. They're fine. It's a bullet, not a nuclear device.