You can try a crane o-ring or an extra power extractor spring.(if one exists) This issue is some of the reason why several manufacturers have come out with more "robust" extractor setups for .308 ARs. Some even use two springs in their design.
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You can try a crane o-ring or an extra power extractor spring.(if one exists) This issue is some of the reason why several manufacturers have come out with more "robust" extractor setups for .308 ARs. Some even use two springs in their design.
I'd try the heavier buffer. It will increase the lock time. This will let the chamber pressure drop a bit more and give the brass a bit more time to 'spring back' thereby reducing the extraction effort. I found this one http://heavybuffers.com/ar10carbine.html . It's not an endorsement, just an example of what's out there. Zediker's book 'Top Grade Ammo' has a section that deals extensively with this subject.
Let us know how it works out.
Stuart
Ugggghhhh......Prior to asking on here, I ordered one of the UBR 2.0 stocks from Magpul. I wanted something a little heavier on back to counter the heavier barrel. I figured it would cost about the same as buying a tool, A2 length buffer, spring, buffer and a fixed Magpul rifle length stock. Those heavy buffers on that sight are expensive. I measured the buffer tube at 7.25 inches from end to end. I'll have to weigh the buffer tube. A friend made a video of me shooting the rifle. In it, I could see flames coming far, far back along the rifle--probably to the ejection port. I'm guessing--if the lighter buffer/spring combination is the culprit--that maybe the bolt opened a little early and allowed some of the gas to escape from the ejection port? IDK if that is possible. Also, the rifle comes with a lifetime warranty. So, if a heavier buffer is needed, I'm assuming the company would provide it?
A lot of (if not most) rifles come from the factory overgassed, some more than others. A heavier buffer will slightly slow down the BCG (cycling) and help the ejection to be less violent. It doesn't hurt to try a heavier buffer but you have to figure out what buffer you have first. On the 5.56 rifles I have that pulled the rims like that the buffer was not the problem.(needed crane o-ring or heavier extractor spring) But the .308 has a much more substantial rim than .223/5.56.
I just put an adjustable gas block in my AR10 (PA-10 to be exact--couldn't pass it up for the price) and that exact problem went away immediately. I'm about to try it again suppressed, probably have to dial it down a couple of notches but expecting good things as well. Someone explained to me that a lot of companies overgas their rifles to guarantee cycling with cheap ammo, as some surplus in 7.62 is really weak as is steel cased .223. Personally I think midlength gas system on a .308 is stupid, but apparently they think otherwise. Quite honestly I wish they wouldn't resort to lowest common denominator thinking like that, but oh well.
If this helps, I have a 26 coil buffer spring and 10.75 inches long. The buffer weighs 3.8 ounces. From what little information I could find, I have not seen buffer springs with only 26 coils.
Im with Hawk, grab an adj block and get it set to cycle how you want.
Personally a fan of the SLR Rifleworks one. Easy clicks to know what setting you're on.
I also strongly suggest an adjustable gas block.
I have fiddled around with all sorts of springs and buffers on numerous AR platforms... 9MM Blowback, .223 /5.56 DI and AR10... the adjustable gas block is the absolute best solution for and AR10. ( IMHO )
It changed my "violent cyclic action" on my PA10 "bargain" SPR into a VERY pleasant .308 AR.
I tried a few different springs, buffers and buffer tube lengths... to little avail... the SLR adjustable gas block far bested all others attempts.
If you'd care to read about my $700 PA10 journey ... it is here..
http://www.ar15.com/forums/t_2_301/2...July-2017.html
Adjustable gas block + suppressor = AR10 worth having. Shooting this thing immediately shows me why Nick Irving felt virtually invincible.
I am looking at adjustable gas blocks now. Looking at the SLR and the Superlative Arms adjustable gas blocks. I'm not sure which would be better. The hand guard is a pain to remove--I had to hold onto it and pound the muzzle brake on my basement floor (I did it on a rug so I wouldn't beat the end of the muzzle break). Not sure which one to buy--I'd rather get one that I could make adjustments without removing the hand guard. Also, I'm probably going to replace the muzzle brake. Down the road, I may buy a Griffin Armaments Optimus supressor (I may get some money in a few months from the sale of a rifle). The supressor is expensive, but seems to work on the types of rifles and hand guns I own. Not sure if I should get a flash hider or a Griffin Armaments flash comp. I resurrected this thread because I've been thinking about this and am currently looking at Black Friday ads. Here's a pic of the rifle again for reference.
https://i.imgur.com/8eJNJxP.jpg