View Full Version : Is their any rational behind using thread lock on a AR pistol buffer tube.

Calico Jack
2 July 2015, 04:54
A buddy of mine had a pistol lower assembled by a gunsmith at a LGS. He bought a law tactical folding stock adapter and asked me to install it for him. I read up on it a saw that it didn't involve anything above my skill lever so I told him I would do it. I took a look at the lower and noticed the castle nut on the buffer tube was not staked which I though was odd but also was going in to make the install easier. Then I discovered that the gunsmith used thread lock on the castle nut and on the buffer tube possibly. From what I have learned thread lock should not be used.

Am I wrong?

Thanks in advance for the answers.

2 July 2015, 05:04
Here's a thread that covered that topic, it may answer your questions.


2 July 2015, 09:24
After trying to take buffer tubes off a few guns that the manufacturer used locktite on the castle nut I would NEVER use it. Even heating with a torch, it makes the disassembly a nightmare.

2 July 2015, 11:22
I was going to say blue Loctite (242) isn't meant for such large diameter fasteners, but I was mistaken:



I prefer staking but I sometimes just use a little 242 if I plan on changing things up in the future. Most people use too much from what I've seen. Especially on a 1"+ tube, a little goes a long way.

2 July 2015, 11:28
My pistol tubes are not staked only because they are temporary until the SBR approval comes through. Some rifles staking is put off until a final decision whether to go with carbine or A5 system. Until staked I don't consider an AR fit for defense duty.

A drop or two of purple (weak) Loctite would serve as a stopgap I suppose, but I still would not trust it for serious work.

2 July 2015, 14:55
No no no you guys are all wrong is so won't sping out and kill someone in the range . [BD]

2 July 2015, 20:06
Castle nuts are cheap.

4 July 2015, 18:45
I just German torque the castle nut. No loctite or staking and hasn't failed me yet on many builds

5 July 2015, 03:22
I put a dab of Aeroshell 33MS on the receiver extension threads, torque the castle nut down good and tight, and stake it. The stake is pretty easy to break when using tools and you're trying to get the castle nut off, but no way it'll back off on it's own if staked properly. Thread locking compound is unnecessary, IMHO.