"three snugs" barrel install method?

[bnanaphone]

In assambling my AR, I read all I cojld on this subject and followed the processes described above. I used anti-sieze on threads, did the tighten/loosen 3x and then went for it. I was installing a Larue HG + bbl nut and to get proper alignment for gas tube, I tightened nut to 81 ft/lbs. Will this be an issue? Should I re-do the whole thing? Thanks.

[Robb Jensen]

In assambling my AR, I read all I cojld on this subject and followed the processes described above. I used anti-sieze on threads, did the tighten/loosen 3x and then went for it. I was installing a Larue HG + bbl nut and to get proper alignment for gas tube, I tightened nut to 81 ft/lbs. Will this be an issue? Should I re-do the whole thing? Thanks.

Should be fine most torque wrenches are off 1-4% anyway. 1lb is nothing.

[bnanaphone]

Thanks for the info, I really didn't want to re-do that Larue Rail again anyway.

[C4IGrant]

J,

This is done in order to work the threads and get a better seat. On the third attempt is when I do the final lock down and line everything up. I don't loosen it to make it line up, but rather tighten it a little more than the book calls for if necessary. I also use Loctite C5-A anti-seize.

This is exactly how we do it right down to the C5.

I also use an alignment pin (that is the size of a gas tube) and check that it is sitting evenly on the barrel nut (not more to one side or the other).







C4

[C4IGrant]

I am going to be mounting a barrel in a Vltor VIS upper & the wrench that comes with it says it is a one time use only part.

Any insite on the wrench, is it a one time use part because it won't hold up to multiple torquing or just because they enclose one with each VIS?

You can use the wrench more than once (FYI).


C4

[C4IGrant]

I think a lot of times people use WAY too much torque when installing barrel nuts. I am also almost positive that excessive torque can be a detriment to the weapons accuracy.

If at all possible I really like to stay between 60-70. If the gun has an anti-rotational system (like the DD and LT rails), I like to keep the torque setting even lower.



C4

[rob_s]

I have installed probably a couple dozen barrels, and had occasion to mess with barrel nuts of one form or another a couple dozen more times. Yesterday was the first time I'd encountered one that wouldn't line up at a torque value I was happy with. I cannot physically get it any tighter and the gas tube is binding enough that the carrier won't drop in as it hits on the key. If I loosen it to the next gap it is not tight enough for my liking given that I'm using a FF tube that attaches to the stock nut. I also buggered up the teeth a bit when the DPMS wrench slipped off the nut.

I'm going to tear the whole thing apart again and grind off that tooth with the Dremel.

Wishing I had not just said "eh, **** it, it's only rubbing a little" and had checked the carrier issue before installing, and loc-titing, the FF tube.

[C4IGrant]

I have installed probably a couple dozen barrels, and had occasion to mess with barrel nuts of one form or another a couple dozen more times. Yesterday was the first time I'd encountered one that wouldn't line up at a torque value I was happy with. I cannot physically get it any tighter and the gas tube is binding enough that the carrier won't drop in as it hits on the key. If I loosen it to the next gap it is not tight enough for my liking given that I'm using a FF tube that attaches to the stock nut. I also buggered up the teeth a bit when the DPMS wrench slipped off the nut.

I'm going to tear the whole thing apart again and grind off that tooth with the Dremel.

Wishing I had not just said "eh, **** it, it's only rubbing a little" and had checked the carrier issue before installing, and loc-titing, the FF tube.

Ya, I see these once in awhile.

Just get another delta ring assembly and try again.

When you are running into high torque values with the DPMS wrench, have someone pull back on the Delta Ring (to remove stress) and you will be a lot less likely to slip off the barrel nut teeth.


C4

[rob_s]

Removed the Delta ring, snap ring, and spring.