Best way to hold upper while TQ barrel nut?

[thisguy65]

I have a Gen I Geissele reaction rod but have found out through talking with more experience people that they can/will shear the barrel extension pin.

[SomeOtherGuy]

I have a Gen I Geissele reaction rod but have found out through talking with more experience people that they can/will shear the barrel extension pin.

I would be VERY interested to hear who those "more experience people" are. The major purpose of the reaction rod is to allow you to tighten barrel nuts (and muzzle devices) easily and without putting stress on the receiver, which is a weaker part than the barrel extension. If the barrel is properly assembled, with the barrel extension properly torqued on the barrel itself, there is over 100 ft-lbs of torque on that joint. You shouldn't be torquing a barrel nut past 80 ft-lbs at most. So if things are correct, there should never be stress on the barrel extension pin, which isn't meant to be a load bearing part anyway, just a locating point.

I've used a reaction rod for several barrel nuts and 15+ muzzle devices with zero issues. It's my preferred way of doing things, although I have also done barrel nuts using receiver blocks.

[thisguy65]

I would be VERY interested to hear who those "more experience people" are. The major purpose of the reaction rod is to allow you to tighten barrel nuts (and muzzle devices) easily and without putting stress on the receiver, which is a weaker part than the barrel extension. If the barrel is properly assembled, with the barrel extension properly torqued on the barrel itself, there is over 100 ft-lbs of torque on that joint. You shouldn't be torquing a barrel nut past 80 ft-lbs at most. So if things are correct, there should never be stress on the barrel extension pin, which isn't meant to be a load bearing part anyway, just a locating point.

I've used a reaction rod for several barrel nuts and 15+ muzzle devices with zero issues. It's my preferred way of doing things, although I have also done barrel nuts using receiver blocks.

Don't shoot the messenger! lol Both commented on why the genII was the release to help put force on the ejection port. However I am with you, I do not like putting stress in to the receiver. Often I use handguards that do not need to be index (BCM KMR for example).

[556Cliff]

Get ready for the Reaction Rod love fest.

I think I'm the only one here that doesn't like it. I would much prefer something like the (not actually available yet) Windham Weaponry barreling jig. I did buy the Geissele Super Reaction Rod hoping that it would solve the index pin shearing problems that you get with the original Reaction Rod but the brass wedge system is a fiddly pain in the ass to use when installing a barrel.

[Wayne Dobbs]

If the barrel is properly assembled, with the barrel extension properly torqued on the barrel itself, there is over 100 ft-lbs of torque on that joint...

The barrel extension is torqued on at the factory (Colt) with 150 ft-lbs of torque.

[thisguy65]

What about the Magpul BEV block?

[TomMcC]

I'm trying visualize how the use of a reaction could put that kind of stress on a steel pin embedded in a steel barrel extension. It seems all the tightening stress would be at the receiver/barrel nut interface. At most the receiver would try and turn as the barrel nut is tightened....and widened the slot where the pin fits in the receiver..not shear the pin off. I haven't use a RR, so I'm not sure that the receiver would even turn upon barrel nut tightening.

[SteveL]

What about the Magpul BEV block?

This is what I use.

[thisguy65]

I'm trying visualize how the use of a reaction could put that kind of stress on a steel pin embedded in a steel barrel extension. It seems all the tightening stress would be at the receiver/barrel nut interface. At most the receiver would try and turn as the barrel nut is tightened....and widened the slot where the pin fits in the receiver..not shear the pin off. I haven't use a RR, so I'm not sure that the receiver would even turn upon barrel nut tightening.

The way it was explain to me is that when tightening the barrel nut there is nothing to hold the receiver from twisting. There's be many reports now that I'm looking for them regarding shear pins and the Reaction Rod.

[Joelski]

Has anybody actually seen this happen with their own eyes, or is this theoretical hogwash?