Case necks scratched on ar 15 fired brass

R

rommel500

Sergeant
Full Member
Minuteman
Sep 9, 2009
289
15
45
SLO,CA
#1
It seems like my bushmaster AR scratches the case necks on .223 brass? It puts a little vertical line on it, would this be an issue? My friends Sabre Defense upper'd AR does the same thing and my POF 308 AR does the same thing to .308 brass.

Is this normal? Anything I can do to fix it? Should I worry about it?
 
#5
Re: Case necks scratched on ar 15 fired brass


If it is what I think it is, the lugs on the barrel extension are scratching the case when it is extracted. You can tell by chambering a case and extracting by hand while you watch it.

I don't think it is a problem, but you can stop it by breaking the sharp edges on the barrel extension lugs. You will not have to do all of them, just the two edges that are scratching the case as it ejects.

Good shooting
Ron
 
#6
Re: Case necks scratched on ar 15 fired brass

Here is what I am talking about, here is a .308 win case from my POF 308 AR rifle.
Fun

 
#7
Re: Case necks scratched on ar 15 fired brass

I agree that this happens as the case is being pulled and flipped out of the chamber. Reducing the the ejector spring tension by trimming a few coils off will decrease this and also decrease how far your brass is thrown. Get it right and the dents should decrease and the brass fall in a smaller pile hopefully around 1 o'clock. Trim too much and ejection will be impaired. Then you'll need a new spring to start over with. In my experience about 3 coils usually works best, at least in an ar15. The DPMS 308 I had did this the worst. These guns are set up for reliability and specifically state to not use reloads. They do not care how bad the brass gets beat up.
 
#9
Re: Case necks scratched on ar 15 fired brass

But with these current brass cases is it ok to reload them?

I guess should just watch them for any signs of the case neck starting to split?
 
#10
Re: Case necks scratched on ar 15 fired brass

Load 'em til they split. You'll find the split cases when you are reloading, I generally find them when I'm feeding them into the resizing die. Occasionally (every couple of months) I find one during the primer seating process.

If you anneal the case necks you'll have a lower tendency to split necks/shoulders, but with the cost and availability for 223 brass I'm too lazy to do that.
 
#11
Re: Case necks scratched on ar 15 fired brass

Necks splitting isn't a big deal. I just shoot them till they split at the scratch as well. I usually get 2 to 3 reloads out of them before they die (unless they get scratched some more).

Only drawback, I suspect would be accuracy since necks with deep scratches may not hold bullets to the same tightness as unscratched (or lightly scratched) necks.

I have observed the cases that split as I shoot do tend to result in flyers about half the time.
 
#12
Re: Case necks scratched on ar 15 fired brass

The feeding ramps by the chamber, on the barrel extension can do that also. If they are just scratches, I won't worry about it.

Deep gouges are a different matter.
 
#13
Re: Case necks scratched on ar 15 fired brass

Back to this topic again, you can feel the scratch with your finger. I was looking at some brass from my friend's AR, his is a Sabre and mine is a Bushmaster and they both have the same marks.

So nothing to worry about and go ahead and load em? We are going to load up some rounds tomorrow so I want to make sure we aren't wasting our time....
 
You must log in or register to reply here.

Similar threads

dzz
.308 win - reloading same brass for bolt action and an AR-10
Replies
14
Views
381
turkey_creek
turkey_creek
J
Fouling past the case neck
Replies
33
Views
1K
JRBullock1987
J
F
Necking up from .260 to .308
Replies
4
Views
155
memilanuk
memilanuk
J
Rough Rust-like finish inside alpha brass necks
Replies
27
Views
705
Dolomite
D
Thumper580
Sooty case neck
Replies
2
Views
173
Marine52
Marine52
Top Bottom
Back
Home
Forums
Merch
Alerts