View Single Post
Old 07-21-2015, 10:10 AM
JMP's Avatar
JMP JMP is offline
Internet Warrior
CGN Contributor - Lifetime
Join Date: Feb 2012
Location: Pacific Southwest
Posts: 17,057
iTrader: 1 / 100%

Originally Posted by ar15barrels View Post
You can't.
The barrel is subject to turning in the receiver while final torque is applied to the nut.
The best you can do is to get within 0.001" IF you have incremental headspace gauges.
If you only have standard go/no-go, you will be somewhere within the 0.004" acceptable range.
That is what I was thinking, and I've been confused why people refer to barrel nut guns as "easy" for barrel swaps. Personally, due to my limitations of gauging and measuring, the 0.004" is about the same as I'd think, which is pretty much just using go and no-go. However, I am wondering if there is a way to mark the barrel to get the threads lined up exactly for where you want to tighten the nut. Could you improve that with a visual mark for thread alignment, or are there still issues with the way the nut engages?

I do not think they are good for barrel "swaps" as you need repeatability. In my way of thinking, it is MORE economical to get one good rifle and 3 different barrels that you can swap. To save money in the long run, I think it is better to go with a non-"nut" system. This is assuming that all your barrels are fit.

That said, I'd give it a try if it were my first rifle, but I already have all the barrellings (in multiples) of 308, 6.5CD, and 243. So, I will say that they made a nice cartridge choice, but a poor one for me since that's what I already have.
Reply With Quote