Heavy bull barrels and FF handguard fitment issues.

[dang472]

I'm building 2 different heavy barreled rigs with components from different companies. I'm having an issue with the inner diameter of the barrel nuts fitting over the barrel. The first build is a 24in DPMS .204 Ruger bull barrel with a Seekins MCSR 15in rail. The next one is a 20in Wilson .223 Wylde bull barrel with a Samson 13.5in rail. Both barrel nut will not get past the gas block area.

I already Dremeled the Seekins nut to fit the DPMS barrel, thinking the barrel was more to blame than a Seekins product. Now I received the next heavy barrel with a different rail and having the same issue.

Is this par for the course with the big AR barrels?

 

[msalm]

Some barrel nuts will let you get away with 1.050" on the barrel diameter, others only 1". If I run into that problem I just chuck the barrel nut in the lathe and open it up to the needed diameter.

 

[dang472]

Yeah I figured I couldn't have been that unlucky to get 2 screwed up setups. I really wish I had a lathe after spending the last 2 nights with a Dremel and 4,000 sanding drums.

 

[AZ2000]

How about a lower profile gas block? Just a thought, had to do it to one of my AR's when I did a build.

 

[dang472]

The gas block isn't installed. The diameter of the barrel behind the gas block step is too large on both barrels.

 

[AZ2000]

Did you call DPMS and ask them if they had a solution for this problem. I have found a couple of times, the manufacture had a new part, but it wasn't up on the web sights yet because it was a fairly new product that was just developed to fix the problem.

 

[dang472]

If it was only the DPMS barrel, I would have called. It appears that with the heaviest of off the rack bull barrels, some rails do not have enough inner diameter to fit. I wanted to confirm that others have run into similar issues.

 

[Thumper580]

I'm not attempting to sound like a smart ass but could they be .223 barrel nuts? Just asking? Good luck.

 

[dang472]

The nuts are for the AR15 platform. It doesn't matter if it's a 6.8, 223, or 458. The 308 series for an AR10 type are different. Besides I am using these for 223 cartridges. The 204 is simply a necked down 222 Remington and the 223 Wylde barrel is in fact a 223 barrel.