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.
I feel bad for him. He spend several thousanda of dollars on a suppersor, two uppers a, lower and a bolt action at this shop. It’s not hard to do it right the first time. Thanks for the affirmation.
Thread lock on the castle nut/buffer tube isn’t needed with proper nut torque and staking, but isn’t going to hurt anything if he doesn’t ever plan on disassembling them.
In the military, you can’t call a ‘time out!’ to tighten up a loose castle nut or buffer tube and there’s a decided lack of armorers at the squad level. Big Army wants things to be as ‘one-piece’ as they get, which is why things are pinned and staked. If they could construct a one-piece bolt carrier group that included the gas key they would, but since they can’t it gets a couple precision whacks to lock the screws in.
In the civilian world, people are more likely to change out things on a more frequent basis, or upgrade as bigger, better deals come along and breaking loose the thread lock is easier than breaking loose a staked nut. As militarymoron says… it’s not right, but it won’t hurt anything in the civilian world where you can call ‘time out’ and go back to the range the next day.
I’ve actually found a staked nut to be much easier to break loose than a loctited one. staking prevents the lock nut from loosening under normal use, but it’s easy to overcome the staking when using the proper castle nut wrench.
a loctited receiver extension and castle nut can be a real pain to remove. i have an earlier KAC M4 lower that had the castle nut and extension factory loctited and i thought i was never going to get that thing off.
If you do ever need to remove loctite and you can strip it to something with no plastic remaining, sticking it in the oven at 200F for 15 minutes will soften the loctite significantly without doing anything to pretty much any metal. I’d want to remove the plastic plunger for the bolt catch first, although it would likely be ok. If you need to go hotter Aluminum doesn’t really care until you go past 400F or so I think, but I could be wrong… anyway, the hotter you go the softer loctite is (but it’ll form an even better bond once cool).
Loctite is a member of the cyanoacrylate family. Same as super glue. Get a super glue de-bonder, let it leach into the threads, and it will deactivate the loctite.
Do NOT get it on any plastic. It will melt that shit like the spit from an Alien’s mouth melted the decks of the Nostromo.
huh - wish i’d known that when i was trying to take that loctited castle nut/extension off. i can however tell you that elbow grease, sweat and swearing do NOT soften nor dissolve cyanoacrylates.
Loctite threadlocker is not a cyanoacrylate it is an anaerobic.
Acetone will not do much to Loctite threadlocker when used on assembled parts. You will need to use heat for disassembly.
The best thing to use to try to remove the dried threadlocker residue once the parts are disassembled is methylene chloride, though even this doesn’t work that great.
It’s an interesting topic. Loctite isn’t required, but may not be damaging for non TDP additions. For it’s own intended use, staking works out fine. Sometimes though, a way of retaining torque could be had without breaking the anodizing that sometimes happen with staking. There are many forms of this, and it takes proper prep. For some items I see the addition as a possible compliment to staking to a point that the amount of staking could be reduced to remove less anodizing to extend component life if was to be disassembled later and reused.
The proper staking for a castle nut will remove the protective anodizing layer from the parts. The reality is that most of these parts will never be removed and nobody would notice.
Less mechanical resistance to movement VS a bonding agent could help some things, but I wouldn’t omit at least some mechanical tension.