Monday, March 17, 2014

MEGA 308 Barrel Review


I've been in the pursuit of a good 308 AR barrel for a while, trying to find the balance between budget, reliability, weight, and accuracy.  I've been through a few barrels, got rid of some for good reason, and not as good for others.


My most recent barrel was a Fulton Armory Titan 18.5" chrome lined lightweight barrel.  It had most of the features I wanted; rifle length gas system, 18.5", chrome lined for reliability, and very light 2lbs6.5oz.  It shot well enough for military standards, but I wanted to squeeze a little more accuracy out of my AR while still maintaining reliability.

Mega Recently came out with their line of 308 barrels that have a Sub MOA accuracy guarantee at 100yrds with match grade ammo.  What did I have to lose?  It was roughly the same price as the previous Fulton I had, and if it didn't shoot well enough, I could get my money back.  I decided to go with the 16" to try and match the weight of the fulton, and had to compromise on going back to a midlength gas system, which would be worth it if the accuracy improved.

Some Initial Observations:

After the barrel arrived, I looked it over.  One thing I noticed was the PRI adjustable gas block fit a little looser than I would have liked.  It was tight on all of my previous barrels, so I'm not sure if that will cause any future issues.

Another thing I noticed was that it fit pretty easy into my MEGA upper receiver.  I would have liked a little tighter fit as well (similar to JP where the have to freeze the barrel, heat the receiver to get things to fit).  It may not be a big deal, but just an observation.

While getting ready to assemble the rifle, I checked the headspace on my DPMS bolt. Dang! closed on the NO-GO Gauge.  I checked the bolt against the Fulton barrel, which headspaced fine.  I called MEGA and talked to one of their technicians, and they recommended picking up another bolt to verify the potential headspace issue.  I had been eyeballing a JP enhanced bolt for a while, so this was a good enough excuse to pick one up.  $165 and a few days later, I had the JP in my hands.  I checked the headspace, and it gauged fine with the MEGA barrel, sigh of relief.  (Interesting note, I couldn't get the JP bolt to close on the GO gauge in the Fulton barrel).  This makes me realize how much variability there can be while building these rifles, and how important it is to check these critical dimensions.

Range Review:

After getting everything together, I wanted to take it to the range and get some baseline data with some 175gr LC matchgrade ammo, as well as challenge the sub-moa guarantee MEGA had.  My scope was dialed in for the previous Fulton 18.5" barrel, so I figured it would still be pretty close with the shorter MEGA barrel....wrong.  I was shooting 16-18" higher than before.  This was pretty surprising since zero shift shouldn't have changed too much, but a few clicks on the scope got back on target.  I will be curious to chrono this barrel and see how it compared to the Fulton (not sure how the melonite coating will affect velocity)

I shot 4 groups total, one which completely missed the target (shooting high), one group to get me on target, and two groups to verify the accuracy.  Target results are below.

Group-3 (100yrds, 175gr LC Match, Caldwell Front rest/Rear Sandbag)
1.24MOA





Group-4 (100yrds, 175gr LC Match, Caldwell Front rest/Rear Sandbag)
0.789MOA


While I wasn't incredibly impressed with the first group, it was only slightly worse than the best group I ever got with the Fulton.  The Second group is what impressed me.  0.789MOA satisfied the MEGA Sub-MOA guarantee, so I know things should only get better with hand loads.

I will update this review when I get some more sample data and experience with this barrel, but for now, I am very happy with the purchase.  
  • Not overly expensive
  • Good material
  • Great accuracy


4 comments:

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  2. I am building a Mega Maten and had the same issue where my bolt closed on the No-Go guage. I am using a bolt from Rubber City Armory which is who they recommend. I contacted Jason Curns at Mega who said I could ship my barrel to them and they would check things out and let me know. I know the barrel is within the 7.62 NATO spec as far as the headspace goes but Jason said that they adhere to the .308 match and the bolt should have not closed on the No-Go gauge. I guess we will see what is up.

    ReplyDelete
  3. I am building a Mega Maten and had the same issue where my bolt closed on the No-Go guage. I am using a bolt from Rubber City Armory which is who they recommend. I contacted Jason Curns at Mega who said I could ship my barrel to them and they would check things out and let me know. I know the barrel is within the 7.62 NATO spec as far as the headspace goes but Jason said that they adhere to the .308 match and the bolt should have not closed on the No-Go gauge. I guess we will see what is up.

    ReplyDelete