Mega Arms 308 Barrel problem

[stihl2much4u]

I have never seen this in any of my AR-15 Barrels. This is from a Mega 20" 308 barrel with matching upper and lower, dpms 308 bolt. Any info would help. My rounds are getting gouged to heck. I'm not sure if this is contributing to my shots being flung all over paper. Thanks
https://www.flickr.com/photos/21361425@N06/15488930100/in/photostream/

[stihl2much4u]

https://www.flickr.com/photos/21361425@N06/15488930100/in/photostream/

[Computalotapus]

I know this is probably a stupid question but is the barrel nut tightened to spec and is there any side to side play when the barrel is mated to the receiver before tightening?

[stihl2much4u]

No side play, it fit like a glove into the upper. The barrel is torqued to 40 lbs. Good questions though

[UWone77]

What kind of gouging?

I had a similar issue while helping a friend build up at .308, but it was the extractor not the barrel.

[stihl2much4u]

Take a look at the pic, if you haven't. It's on the right hand sides of the feed ramps right before the chamber. It's gouging the sides of the bullets when they feed. I'm hoping my bolt isn't causing this upon extraction.

[Computalotapus]

Take a look at the pic, if you haven't. It's on the right hand sides of the feed ramps right before the chamber. It's gouging the sides of the bullets when they feed. I'm hoping my bolt isn't causing this upon extraction.

I could be the bolt like UWone77 mentioned


Take a look at the pic, if you haven't. It's on the right hand sides of the feed ramps right before the chamber. It's gouging the sides of the bullets when they feed. I'm hoping my bolt isn't causing this upon extraction.

His picture wasn't showing for me so I uploaded it to my site and this is what is causing the gouging. looks like the bolt pulled on the lugs on the feed ramps

http://www.computalotapus.com/images/gouge.jpg

[UWone77]

I agree with Comp's diagnosis.

I mention the Bolt, as not only a friend, but I've also had my own DPMS .308 Bolt that was causing me problems with extraction and denting cases. If you're able to, try a different BCG. That's how I narrowed my problem.

[SINNER]

I just had a DPMS bolt not headspace on a Rainier Ultra-match .308 barrel. It tested out just fine on a DPMS barrel and a JP barrel. JP enhanced bolt headspaced correctly on all three barrels. It felt like something was binding trying to pull it out of battery with the charging handle. That caused me to actually break out the gauges.

[stihl2much4u]

Thanks a bunch! I will order a different bolt. I have seen the jp bolt on Rainer. Thanks again

[FortTom]

I agree with Comp's diagnosis.

I mention the Bolt, as not only a friend, but I've also had my own DPMS .308 Bolt that was causing me problems with extraction and denting cases. If you're able to, try a different BCG. That's how I narrowed my problem.

Not long ago, I purchased a DPMS that I could confirm only had about 20 rounds through it. Came from an estate sale. Before I ever fired a shot, I noticed that the bolt was sticking or would not properly seat went sent forward to battery. I purchased an aftermarket NiB bolt for it and problem solved. I too suspect quality problems with the bolt. I bought the gun at a very cheap price, but had no time to research it, it was one of those take it now or pass on it situations. But after acquiring it, a little research led me to others who had problems with DPMS .308 bolts. Not sure if this helps or not, but I'm quite sure I would have had problems, had I taken it to the range the way I got it, and put 100 or more rounds through it.

FT

[stihl2much4u]

I agree with Comp's diagnosis.

I mention the Bolt, as not only a friend, but I've also had my own DPMS .308 Bolt that was causing me problems with extraction and denting cases. If you're able to, try a different BCG. That's how I narrowed my problem.

Do you have any recommendations for a new bcg? I've been looking since this post but can't seem to narrow anything of quality down. Thanks

[SwissyJim]

not sure of your budget, but Fulton Armory has a following on 308ar, and I love my Shadow Ops Weaponry NiB bcg... solved my issues in my LR308

[stihl2much4u]

I've already got a bunch of money dumped into this thing, so my budget is pretty much whatever will make it operate correctly. Thanks for the idea. I'll check them out.

[UWone77]

I've used AIM .308 BCGs with good luck. The problem is, in the .308 world, there isn't a BCM type gold standard BCG or bolt, so it me, it's a real crap shoot. I would also look at Aero.

[Gaspipeshooter]

The .308 build I did, I got the BCG from CMT and sent them the upper and they headspaced it. Their BCG is of high quality so far as I can see.

[Diazm50]

Could it be the upper receiver not perfectly square where the barrel mates up?

[stihl2much4u]

Figured I'd let you guys know the problem has been solved. I bought the bullet and got a jp bcg. Just came in from shooting and my groups are tight and consistent, finally! Thanks again for all the help. Here is a list of components on the rifle. Everything seems to be working in sync now

Upper&lower Mega Maten
Barrel 20" Mega
Adjustable gas block syrac
rail fortis switch
muzzle break lantac dragon (worth every nickel)
Bolt jp low mass
buffer jp silent spring
stock luth-ar
grip magpul moe+
trigger geissele sd-e
standard lpk