My AR Puts a Dent in The Brass Case

S

Stealth1959

New member
MY AR will put a small (1/16th in) dent in all of the fired cases. Can someone tell me why this happens and how to correct it? Can I reload the cases with the tiny dents in them or do I toss them?

Thanks in advance. /ubbthreads/images/graemlins/bowingsmilie.gif
 
I'd reload them dents don't hurt any thing

Although I would keep track of how many times you have reloaded them and watch them and they will eventually crack were they are dented

Does your AR have a shell deflector?
 
I want to say that somewhere I've seem someone put a piece of self-adhesive velcro (hook side) on the shell deflector to decrease the dents, but I don't remember where.
 
Quote:
I want to say that somewhere I've seem someone put a piece of self-adhesive velcro (hook side) on the shell deflector to decrease the dents, but I don't remember where.



I did it. (wasn't my idea though) It makes a HUGE difference in the manner in which the cases are thrown from the rifle, too. They go more to the 3:00 position (rather than 4:30) and not nearly as far away.
 
It is pretty common with AR's the dents will not hurt anything and the next time the cases are fired that dent will be pushed out and a new dent in another spot will sho up. I have seen and heard of guys tapeing or glueing hunks of rubber or velcro to the shell deflector to try and stop it. That may work to a point. You can also fool with the ejector to lighten the force of ejection or try and change the angle of ejection but then you are risking FTE's "failure to eject) So your choices are ignore it, try to halfazzed pad the deflector to ease the possible damage, or try to fix it correctly but be ready for a whole lot of headaches unless you know what your doing, or take it to some one who does.
 
Some years ago I was able to aquire some used .223 military brass. All of them had a small dent on them like described above. What is funny the brass also had what appeared to be a plugged hole on the side of the brass casing just below the neck. It was very smooth but the spots were obvious. It was like the brass had a hole in it and some one took a piece of gum and filled in the hole (of course this was with brass).

With reserve I reloaded a few and tried them. They shot great! Sub MOA for sure at 100yds. Needless to say I reloaded all of it and to this day, I am still cycling through some of the last of it.

I'm no expert by any means, but I have been pleased with the brass with a dent and gum filled in hole.

By the way, any experienced .223 reloaders ever see this??
 
How many times do we have to see the same question asked in the same day?
No search needed, just look at the last 8 hours of posts!!!!

Jack
 
I can see why Jack gets a bit frustrated sometimes, but it's one of those common traits of the AR-15 and some other autos. It's very common to see these dents, and they can look a little different on individual rifles. The ejector plunger spring that many builders install tends to be on the long side. From a functional standpoint, it's better to have it to strong or to long, rather than to weak or to short. (Gee, that sounds familiar)

There are a couple factors that contribute to the dents, their placement, and severity. The major factor is the ejector spring being to strong or to long. This causes the ejecting case to be slapped hard against the locking lugs, usually just below the shoulder, when the case is just clearing the chamber. The distance below the shoulder will vary with the speed of the cycling bolt. If your rifle is tossing the empty cases more than 5 feet from your shooting position, the ejector spring is longer than it needs to be. The extra tension on the plunger puts a more violent spin on the case causing it to hit the shell deflector or even the ejection port. This causes a different characteristic dent that can be more random in location and severity. These dents are mostly cosmetic and not normally a big deal for reloading. Most rifle builders are fully aware of these dents, but it would be more time consuming to tune the ejector spring. Besides, for liability reasons, Many builders won't warranty your AR-15 if your using reloaded ammo.

There is another thing that can contribute to the dent severity, and that is the carrier/bolt speed as it moves back. A stronger buffer spring like the Tubb CS spring will slow the carrier and delay the unlocking of the bolt. There are other benefits to the Tubb spring, but that's not what we are talking about here. Tubb also makes CS springs for the ejector and extractor, along with some other good AR-15 parts.

You can completely eliminate the dented cases without causing feeding or ejection problems if you checkout the link below. It has the pictures and instructions to tune your ejector spring. You might want to checkout the Tubb link as well, since it can relate to the dents and other cycling issues. My AR-15 puts all the fired, un-dented, cases in a neat little pile 3-4 feet from the bench. The cases look like they were fired in a bolt action rifle rather than an AR-15.

http://www.gswagner.com/arejector/arejector.html

http://www.davidtubb.com/tcom_images/ar15_images/cs_buffer.html
 
Lol i hear ya Jack. /ubbthreads/images/graemlins/smile.gif
the thing that perplexes me is the original poster is the same guy in both threads, made only a minute apart... /ubbthreads/images/graemlins/confused1.gif
 
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Jack needs to calm down, in the years I been here I seen the same questions asked by the new guys that join this site. That was a rather rude and unprofessional response from a moderator.

t/c223encore.
 
Nice link SodakJim, I was just gonna put some velcro on the part of the upper that the brass always hits, but that is a much better solution. Just one question, though, when you cut the spring do you sand the part you just cut to smooth it so that it won't scratch the part that it sits against? Or can I just cut it and call it good?
 
A dremel with a disk cutter will cut it fairly smooth and flat. If you want, you can turn the spring so the cut-off end is against the end of the hole in the bolt. Take it slow, use safety glasses, and remember you want the spring to fully extend the plunger plus maybe .020 to .030 compression on the spring. I had a couple spare spare springs on hand, in case I took to much off. It's good to have a few AR spare parts on hand. I planned on replacing the ejector and extractor springs with the Tubb CS (Chrome-Silicon), but so far no problems with the stock springs.
 
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Jack needs to calm down, in the years I been here I seen the same questions asked by the new guys that join this site. That was a rather rude and unprofessional response from a moderator.

t/c223encore.



Agreed. I hit the "ok" button twice. Simply an accident. I didn't mean for anybody to get on Prozac over it. /ubbthreads/images/graemlins/smiliesmack.gif
 
Quote:
Quote:
Jack needs to calm down, in the years I been here I seen the same questions asked by the new guys that join this site. That was a rather rude and unprofessional response from a moderator.

t/c223encore.



Agreed. I hit the "ok" button twice. Simply an accident. I didn't mean for anybody to get on Prozac over it. /ubbthreads/images/graemlins/smiliesmack.gif



Not directing this at Jack.....but it would be nice if we had the option to delete our own posts when this happens. I have posted twice by accident also, and I would have deleted one of the posts if I had the means to do it.
 
SodakJim, thanks for the links on the tuning, been doing it for years on 1911's, should have known the info was available for the ar's too.
 
My spring must be really long. I let my dad plink with mine a bit with some cheap Monarch steel case ammo, the cases landed about 15 ft behind him, and about 6 feet to the right!
 
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