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Posted: 7/15/2009 7:17:10 PM EDT
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Hey all, first post, sorry if this has been asked before but searching didn't bring anything up.
I just assembled the lower half of my AR (Stripped Lower + LPK + stock). It's going to be a rifle-length build with an A2 stock (to be NY-compliant). I followed the instructions in the AR15.com library on lower receiver assembly. Everything went fine... but after getting it all together I realized I forgot to torque down the buffer tube. It is on "very hand tight" (and had bottomed out), but that's all. What I want to know is... is it worth ruining the Loktite job and possibly the stock screw to take it back apart and properly torque down the tube? What are the consequences of an improperly torqued tube on an A2 stock over time? I've seen some guides suggest 15 ft-lbs, some say 35 ft-lbs... what do you recommend, assuming I should torque it? Thanks! |
| With an A2 stock the worst you'll experience is a rattly, loose stock. There IS a torque standard for the receiver extension (the real name for this tube), and it's listed in the tacked thread at the top of this forum: 35-39ft/lbs for a rifle receiver extension. The standard GI barrel wrench also has a notch for the shape at the end of the receiver extension so you can properly torque it. The manual doesn't call for any sort of thread-locker, and I'd stay away from that stuff in any case-it's a PITA to remove a part you've locked with Loctite. |
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Quoted: In using Loctite on the stock screw and not torquing the receiver extension may in itself cause you a problem. I've seen many stocks where the stock screw won't break loose (because of the Locktite) but the receiver extension will spin loose from the receiver leaving the tube in the stock due to the fact that holding the tube while in the stock is a bit difficult. Should you get it loose I would torque the extension and not use Locktite on the stock screw. I should be clear, the Loctite is on the stock screw. The buffer tube threads are clean. Thanks for the reassurance. |
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Quoted:
Quoted:
In using Loctite on the stock screw and not torquing the receiver extension may in itself cause you a problem. I've seen many stocks where the stock screw won't break loose (because of the Locktite) but the receiver extension will spin loose from the receiver leaving the tube in the stock due to the fact that holding the tube while in the stock is a bit difficult. Should you get it loose I would torque the extension and not use Locktite on the stock screw.
I should be clear, the Loctite is on the stock screw. The buffer tube threads are clean. Thanks for the reassurance. A standard stock screw has two features: a drain hole all the way through it, and a cutout with a nylon thread locking piece in it. Not Loctite, but an insert. If the standard screw is installed correctly (basically just bottomed out into the countersink in the butt plate), there should be no problem with holding the stock firmly and unscrewing that screw with an appropriate screwdriver. That's the key: the screw head is REALLY big, so you need a REALLY big screwdriver to get a solid grip on the screw. And you can expect to have to use plenty of muscle with that big screwdriver until the nylon insert clears the threads in the extension tube. |
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A standard stock screw has two features: a drain hole all the way through it, and a cutout with a nylon thread locking piece in it.
I have never seen a nylock insert in a stock screw. Not to say that someone isn't doing it, just never seen it. Must be particular to a certain manufacturers stock? Actually as long as you didn't use red loctite you'll be OK. Blue locktite is meant to be unscrewed. Red Loctite required heat to release. |
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Quoted: No offense but I see these with blue Locktite with some frequency. BushMaster for one has released these from the factory like this. Not much left for me to learn about the appropriate size driver head, the problem as I was trying to describe it is simple. The stock screw can end up being tighter than receiver extension in the receiver. As I'm sure you've done a few of these I'm surprised you haven't seen one come apart (or not come apart) like this.Quoted: Quoted: In using Loctite on the stock screw and not torquing the receiver extension may in itself cause you a problem. I've seen many stocks where the stock screw won't break loose (because of the Locktite) but the receiver extension will spin loose from the receiver leaving the tube in the stock due to the fact that holding the tube while in the stock is a bit difficult. Should you get it loose I would torque the extension and not use Locktite on the stock screw. I should be clear, the Loctite is on the stock screw. The buffer tube threads are clean. Thanks for the reassurance. A standard stock screw has two features: a drain hole all the way through it, and a cutout with a nylon thread locking piece in it. Not Loctite, but an insert. If the standard screw is installed correctly (basically just bottomed out into the countersink in the butt plate), there should be no problem with holding the stock firmly and unscrewing that screw with an appropriate screwdriver. That's the key: the screw head is REALLY big, so you need a REALLY big screwdriver to get a solid grip on the screw. And you can expect to have to use plenty of muscle with that big screwdriver until the nylon insert clears the threads in the extension tube. |
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Quoted:
Quoted:
No offense but I see these with blue Locktite with some frequency. BushMaster for one has released these from the factory like this.
Quoted:
Quoted:
In using Loctite on the stock screw and not torquing the receiver extension may in itself cause you a problem. I've seen many stocks where the stock screw won't break loose (because of the Locktite) but the receiver extension will spin loose from the receiver leaving the tube in the stock due to the fact that holding the tube while in the stock is a bit difficult. Should you get it loose I would torque the extension and not use Locktite on the stock screw.
I should be clear, the Loctite is on the stock screw. The buffer tube threads are clean. Thanks for the reassurance. A standard stock screw has two features: a drain hole all the way through it, and a cutout with a nylon thread locking piece in it. Not Loctite, but an insert. If the standard screw is installed correctly (basically just bottomed out into the countersink in the butt plate), there should be no problem with holding the stock firmly and unscrewing that screw with an appropriate screwdriver. That's the key: the screw head is REALLY big, so you need a REALLY big screwdriver to get a solid grip on the screw. And you can expect to have to use plenty of muscle with that big screwdriver until the nylon insert clears the threads in the extension tube. I didn't say you wouldn't see screws with blue Loctite. I said the "standard screw" had a nylon insert. Using non-spec parts changes the whole equation. |
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