Lower flex when torquing buffer tube

[mike_f]

That is an old manual and a mistake. 40 inch pounds = 3.33333 foot pounds, think about it.

Well I'm old (and likely a mistake).

When I started assembling AR carbines the available locking ring wrenches (pre castle nut) were about 4 or 5 inches long:

OldWrench.jpg

So a greatly reduced torque value vs a rifle extension didn't seem outlandish. I used more than 3.33 ft-lbs, but no where near 40 ft-lbs.

I learned something today, so I'll fix it.

[Dutch110]

I use the Gorilla Method. No torque wrench. Just an armorer's wrench (pipe wrench works in a pinch too) and I keep putting pressure on it until I grunt like a Gorilla. Or the wrench slips. It's fun for the whole family. Oh and definitely drink at least a 12 pack of Old Milwaukee before attempting this. It helps with lubrication. The more you know.......

[JediGuy]

Someone should make a polymer brace like the one that lines up the receiver extension with the pistol grip. If they swung the polymer forward a bit, they could also have a surface for clamping the middle of the receiver in a vice.

Robertthetexan pointed to plastixrevolution for some good products, I wonder if they could put this together.

Essentially, drop the receiver “down and back” into the jig, then slide the receiver extension forward into the end plate/castle nut and then receiver.

[rpoL98]

Here ya go.

i wonder if something could be rigged with the Geissele buffer tube tool jig, add on some steel parts to extend to the pistol grip boss. like somebody said, the Geissele jig is only half the equation. so that the whole thing could be clamped in a vise.

[JediGuy]

I’m going to reiterate the preference for a strong polymer here. At scale, we wouldn’t be faced with Geissele + aluminum prices for something that could be effectively printed.

[Hammer_Man]

The receiver was probably flexing like crazy because you didn’t lube the threads. Lube the threads of the RE, and receiver with Aero Shell, and torque to 40 ft. lbs.

[m4luvr]

50 bucks - Kley-Zion Buffer Tube Buddy - it works

[99cobra2881]

The receiver was probably flexing like crazy because you didn’t lube the threads. Lube the threads of the RE, and receiver with Aero Shell, and torque to 40 ft. lbs.

Is the torque spec in the manual for lubricated threads versus dry?

IME, lubed fasteners will be overtorqued by the time the tq wrench clicks.

Thats my engine building experience where the tq specs are for dry non lubed fasteners.

I understand this is not an apples to apples comparison but the fastener being torqued doesnt care and neither does the tq wrench.

[556Cliff]

Is the torque spec in the manual for lubricated threads versus dry?

IME, lubed fasteners will be overtorqued by the time the tq wrench clicks.

Thats my engine building experience where the tq specs are for dry non lubed fasteners.

I understand this is not an apples to apples comparison but the fastener being torqued doesnt care and neither does the tq wrench.

Yes, the torque spec in the TM is for lubed threads. Barrel nuts, rifle receiver extensions and castle nuts all get lube.

[Hammer_Man]

Is the torque spec in the manual for lubricated threads versus dry?

IME, lubed fasteners will be overtorqued by the time the tq wrench clicks.

Thats my engine building experience where the tq specs are for dry non lubed fasteners.

I understand this is not an apples to apples comparison but the fastener being torqued doesnt care and neither does the tq wrench.

Yes, the torque spec in the TM is for lubed threads. Barrel nuts, rifle receiver extensions and castle nuts all get lube.

The TM specifies lubricating the threads with Aero Shell 64 grease. To answer your other question, yes there will be a difference in final torque when it comes to lubed vs. non lubed. That’s why it’s important to know if the manufacturer specifies lube or not.

In regards to the receiver extension, it’s very much the same situation as the barrel nut. You’re torquing a steel nut onto an aluminum component. Without lube, these two metals create friction and you run a high chance of stripping or galling the threads.