I installed a slap plate about a year ago and ever since the castle nut works loose after every outing. Did I miss a step when I re installed the castle nut ?

A drop of blue Loctite on the threads has always done the trick for me.

ETA- Book beat me by 30 seconds.

Watch out foreman...I here Book likes to assist w/ a "clawhammer'.

J/K ya Book.

I took a 1/4" cold chisel & staked my castle nut in two of the slots on my SLAP equipped rifle.  Two classes later & still no issue.

7mm

Now that we're on the topic, I've never staked my castle nut before, and I would like to for the two builds I'm working on.  I've searched the BIY forum for a "how to" and come up empty.

Is it as easy as lining up a punch and giving it a whack?  It seems easy enough, but I don't want to jack it up.

That's pretty much it.



Even saw people using those auto-punches. You know...the kind you used in middle school to boost cars, know the kind I'm talking about?

 

I might use green loc-tite I use it on my scope mounts...

don't do this. go buy a spring loaded centering punch and give the plate about 5 pushes to displace metal into the notches on the nut.

I use a flat tip screwdriver ground down to a little rectangle tip that gives a good square stake. looks like the factory stakes and is big enough to hold up, but not to big to look bad or keep you from being able to get it off again later.  I start at an angle in to get it started, set up the stake then roll it over straight to finish it up. Just go slow and easy and you will get a feel for it.  

Put the edge or tip of whatever your staking tool of choice just past the center of the plate, leaning back towars the reciever, so the strike drives material rearward toward the slot in the nut. Give it a good tap, see where your at, put it back in the dent at the same angle, and give it a tap roll it more upright, tap, a little more, tap, and then tap it straight up. Creates a very good, solid stake that looks good too.

I do 3. One at the closest slot at 6 0'clock, then 2 more at about 10- 2 or 3-9 depending on where the castelations line up. Best part is is easy and free, except for the screw driver part. A little screwdriver is too thin, but a regular sized snap-on 6 in is perfect.  And if you have an older or off brand nut, it may have half moon castelations, just use a small round punch in the same way and it will come out nice as well for that type.

Thanks for the how-tos.  I guess it is "that easy."



I understand the benefits of staking, but why no Loctite?  It's a pretty common practice- not saying that it being common makes it right.  I'm just interested in why you think it's a bad idea.

I have seen NM Ar's that were literally held together with red locktite. And a few 289's too.

It has its place and is useful, but I don't see it as being bad. The green is one of my favorites. blue is easily removeable, and even the red is with some heat. So I would like to know as well.

Any good pics of one that is staked ?

I'd take a picture but I'm at school so it'll take a few months.

Is there anything special you need to do in order remove a castle nut that is staked?  I was hesitant to just take the wrench to mine.  Need to install a SLAP.

no, just twist it off. the staking should not be enough to resist a wrench, just the tiny rotational forces of a nut trying to back off...

well, first, because it can fail. and you can't tell it has failed till it has failed. blue is what I put on scope rings, buis, etc. it has failed even on those loads and they are not critical. red is what we used to call "stud locking" compound. as in engine studs... once it's on, you'll need some serious heat to get it off and that's not what I want on my RE or receiver of my gun. the only application I see for red on a gun is a gasblock, or maybe carrier key.

staking works, is easy to do, and is visually confirmed every time you pick up the gun. there's a reason to use loctite, and there's a reason to stake or safety-wire. you'll never see loctite being using on critical components of racing motorcycles, cars, or aircraft. these are generally thought of as serious use applications.

or use this - Automatic Punch

Yeah that's what I was talking about. And that's where I bought my punches. But I walked in.

 

Auto punch is fine, but doesn't give the results I want. It has it's uses, and that's not one of them for me. But if that's what you have then use it. There's also something about using your hands and technique that's a satisfying part if it.

Something else you can do, and this is for really hard core use or when you have some out of spec parts, is to assemble it backwards with the castellations forward and stake material into the castellations. Les Baer supposedly does this. I have seen it and done it once. I works great and will never loosen. The parts are generally un useable if you take it off. I have seen the same technique used on helicopters for certain applications with a specific type of washer. Very very rare and usually an engineering band aid fix to get around clearance issues or lack of ability to cotter pin correctly. I have seen some strange safety methods working on helos for 17 years.

If you roll the stake over and into the nut, you run less risk of damaging the nut and can reuse it, it will just have little divots in it, the plate will break off it's little pieces you rolled over. If you center pinch or auto punch the crease in the joint, you will disrupt both pieces.

Heres a link to a picture of one that is staked:
Staked Castle Nut

Yep thats how mine turn out. Looks good square notch square stake. Every now  and then you find a nut with round notches and the round punch looks great. I like stuff to match. It's a nice touch. Looks professional and detail oriented. That's how I was taught to work on aircraft and it just flows over to gun work.

I have seen nuts with1- 2 recesses,  4, and a 6 and even one without. And I wish I had the colt stakeing tool, they probably use an arc welder then stake over the bead! They are usually pretty damn good.

End of the day there is no wrong way, just different ways.

Yep.  My Smith and Wesson has a more sloppy look but it gets the job done and its not like its noticeable.