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Discussion Starter · #1 ·
Just purchased a new AR15 and after shooting several rounds I have noticed the cases are being dented from the protrusion at the rear of the ejection port. The cases are being ejected to far to the rear I think. Is there a way to make the case eject more forwarded preventing the denting issue or is there something I'm doing incorrectly?
 

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Post a picture of a case if you're really concerned, but:

Denting usually isn't much of an issue. Even if you reload, dented cases work fine.

The AR throws cases back. Thats why that "thingy" (case deflector) at the rear of the port is there. To keep cases from hitting left handed shooters in the face.

Unless there is SEVERE damage to the case, don't worry about it.
 

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Where does the brass land? What angle? What ammo? What gas system length and barrel length? Which buffer weight? Gas port diameter also comes in to play, many cheaper ARs are overgassed. A heavier buffer could slow things down nicely.
 

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i think he has a 24" rra. that extra length allows for a more stiff jet of gas throught hte system. prolly needs a heavier buffer to compensate for it
 

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Didn't realize it was so long. 24" is a bit much for rifle length gas, i hope the barrel maker knew to go with a smaller gas port. Could take some thought to increase carrier/buffer weight.
 

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Discussion Starter · #6 · (Edited)
i think he has a 24" rra. that extra length allows for a more stiff jet of gas throught hte system. prolly needs a heavier buffer to compensate for it
Yes Jon your right. It is a RRA LAR15 24" Varmint SS match bull barrel made by Wilson. Chrome bolt and chrome match trigger set. And I don't know anything of the answers ask in the previous post. And friend also has a 20" RRA LAR15 that does the same thing. I just did not want to put my Lupua brass through it doing this. I assume you guys are talking about changing out the spring on the stock. So how would you know which to go with?
O'yea the brass lands at about 20 to 26 degrees to the left.
Sorry for the stupidity.
 

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since its brand new contact rra first. their cs is decent enough
 

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Left handed rifle? Since the casings are going to the left? If it is running that hot you can put an H-2 buffer in it. That is rare that both would be denting cases. The gas port on that barrel should be around.090 to.100. My question is are these "*Reloads" or some cheap ammunition you are shooting? If so you are rolling the dice regarding pressure! What does the primers look like after the are fired?
As stated some pictures would help.
03
 

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Left handed rifle? Since the casings are going to the left? If it is running that hot you can put an H-2 buffer in it. That is rare that both would be denting cases. The gas port on that barrel should be around.090 to.100. My question is are these "*Reloads" or some cheap ammunition you are shooting? If so you are rolling the dice regarding pressure! What does the primers look like after the are fired?
As stated some pictures would help.
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I'm going to assume that since he is running a 24" barrel that he probably isn't running a carbine stock/buffer/spring combo and has a rifle weight buffer already. An H2 is lighter than a rifle buffer.

Check Brownells for a heavier spring. Also the ejector and extractor can be checked to see if you have too much of a grasp on the case rim or not enough.
 

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Doc You are CORRECT! Brain Fart on my end!
Reloads and ammunition is a concern for me here!
I just can not see the guns running that hot!
03
 

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Discussion Starter · #11 ·
Doc You are CORRECT! Brain Fart on my end!
Reloads and ammunition is a concern for me here!
I just can not see the guns running that hot!
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It does it with Walmart Remington 55 gr and my 60 gr V-Max reloads at 2700 FPS. I loaded them at COL 2.246 and the store bought are 2.230. I have sent an email to RRA (why didn't I think of that). Thanks guys. and I meant they eject to the right.:eek:
 

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Let's get that ejection angle straightened out. You said about a 25 degree angle? From straight ahead where the barrel is pointing. Or more normally, if the barrel is pointing to 12 o'clock, then the brass is ejecting toward 2 o'clock? And how far away, six to ten feet? That would make sense if the brass is hitting the deflector hard, it would bounce forward to around 2 o'clock. Too long a gas pulse due to the extra 4" of barrel past the gas port.

If that's a fixed stock make sure it has a rifle buffer (5.5 oz?) and rifle spring (about 13.5"?). Also look at your bolt carrier and see if it's the M16 kind and properly sheilds the firing pin. Any extra weight might be your friend.
 

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Discussion Starter · #13 ·
Let's get that ejection angle straightened out. You said about a 25 degree angle? From straight ahead where the barrel is pointing. Or more normally, if the barrel is pointing to 12 o'clock, then the brass is ejecting toward 2 o'clock? And how far away, six to ten feet? That would make sense if the brass is hitting the deflector hard, it would bounce forward to around 2 o'clock. Too long a gas pulse due to the extra 4" of barrel past the gas port.

If that's a fixed stock make sure it has a rifle buffer (5.5 oz?) and rifle spring (about 13.5"?). Also look at your bolt carrier and see if it's the M16 kind and properly sheilds the firing pin. Any extra weight might be your friend.
Boy, I didn't know this was going to be so hard.:) Pointing the barrel at 12:00 o'clock the brass is ejecting at about 4:00 (back and to the right) and landing about 10 feet away. My chrony has vel. at about 2700 fps. Thanks, i'll check the buffer weight and spring length.
 

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4 o'clock is about what you want. And a pile at ten feet.
 
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