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View Full Version : Stake the Magpul ASAP to Castle nut?


Pappabear
01-16-10, 01:22
Who stakes em?

Who lock tites em?

Who just uses their wrench and checks from time to time?

Trying to decide. My Colts and LMT were staked very well from the factory. It was a pisser to get them loose.

aslink
01-16-10, 01:28
I plan on staking mine. I first want to run it a bit and make sure I like it as well as the build itself. It's my first build so I just want to make sure before I lock it down.

Ken

B.O.W.
01-16-10, 02:43
Stake and loctite. my stake losened up some how, stock rotated and buffer retainer and spring fouled up in trigger. had to change them out in class.

CaptainDooley
01-16-10, 10:57
I've staked both of mine. They're kind of a biotch since they're not the same size as a GI endplate and they're made of something tougher... but I they're both staked and haven't seen any movement yet.

mp43
01-16-10, 11:27
My two cents.

Don't put Loctite on receiver/buffer tube threads.
Some put it on the castle nut but Blue Loctite won't hold up in heat; Red Loctite holds up better but can be worse than staking to get it off.

I allways stake my castle nut. I set the receiver on a vise, put Brownells Action Lube Plus on the receiver/buffer tube threads and screw the tube / castle nut in to hold the retaining pin. Similarly I apply lube to the threads where the castle nut will be screwed, which helps keep the tube straight when you tighten the castle nut. I usually put the stock on at this time to help align the tube.
Once I have everything in I hand tighten the castle nut and recheck alignment. Then I get a castle nut wrench and slowly tighten the nut as hard as I can while supporting the stock. After this I get a torque wrench and SLOWLY (using one hand to keep the wrench on the castle nut) torque to 25 foot/pounds. Some people don't torque to a specific number, they just tighten the hell out of it. Some manuals have the torque as inch-pounds, much less than foot-pounds. YMMV.

Staking is easy. Get a hard sharp pointed punch and make a preliminary indent on the ASAP. Then I get a Starrett Auto Punch, and keep "punching" to enlarge the hole in the ASAP into the castle nut. The stake must be made to ensure that the metal flows to the right side of the square cutout on the nut; that way it will prevent the nut from loosening . If it doesn't your castle nut can come loose.

NB:
1) Because of the Magpul ASAP design you need a compact Castle Nut wrench that only engages one of the cutouts on the nut.
I use this from Brownells...
http://www.brownells.com/.aspx/pid=21254/Product/AR_15_M16_M4_BUTTSTOCK_TOOL

2) Use a castle nut that is hard enough to engage the wrench and not strip. After a few bad experiences I use castle nuts from Colt, and LMT.

3) The Starret auto punch is this one
http://www.brownells.com/.aspx/pid=12619/Product/AUTOMATIC_CENTER_PUNCH

I believe in staking. Good luck.

Jorge

SeriousStudent
01-16-10, 11:32
I staked mine. Not hard at all.

I mounted the lower on a receiver block I bought from Brownells. A friend has a cold chisel that he ground down specifically for staking castle nuts.

A few taps with a two-pound sledge, and it's good.

As in many of life's little chores, the right tools make things easier.