Remage barrel keeps shooting loose

[Vicodan]

So here is the deal. Twice now, a remage barrel nut barrel in 284 has come loose after shooting. The first time, I hand tightened (no torque wrench) the nut and "tapped it with a hammer". After 10 or so rounds, it twisted loose.

2nd time round, I torqued it down to 100 FT Lbs with a torque wrench. Shot 50 rounds trying to find a load. When I got home to clean the barrel, it was loose.

What is going on? Has anyone had this experience? I am going to check the twist on the barrel, to see if it may be opposite to the tenon threads. I honestly can't think of another reason.

 

[savagedasher]

Sounds like you don't have a parallel mateing surface Action surface not straight With the bore Lug not the same thickness. Best way to check is with a marker you should have full contact . Your correct in checking the twist . Larry

 

[primer popper]

The nut may be cracked. Remove & inspect nut.

 

[savagedasher]

The nut may be cracked. Remove & inspect nut.

I don't think he would get 100 ' # with a cracked nut . Larry

 

[Vicodan]

Nut is not cracked. Everything looks good. I am going now to determine twist direction.

 

[rayjay]

I don't think he would get 100 ' # with a cracked nut . Larry

I'm pretty surprised he got to 100 lbs without cracking the nut. Not much meat there and all the wrench slots are bad stress risers and also decrease the cross section area.

 

[rayjay]

Sounds like you don't have a parallel mateing surface Action surface not straight With the bore Lug not the same thickness. Best way to check is with a marker you should have full contact . Your correct in checking the twist . Larry

This makes the most sense to me. I had been coming up with zero ideas.

 

[Vicodan]

I forgot to mention this happened on 2 different actions. The 1st was a Lone Peak razor. The 2nd was a Rem 700. The Lone Peak now has another remage barrel sitting happily.

I cant detect any mating surface issues.

I checked the twist, and it is correct (damn, that would have made this easy).

 

[rayjay]

I would chuck the bbl in the headstock of the lathe and indicate off the chamber and muzzle and then screw on the nut and action and rotate the headstock by hand and look for any runout. You would need a precision fitted rod stuck down the bolt raceway to indicate off the back end of. I would also want to put the bbl on some vee blocks and check it for straightness.

Just throwing out random ideas. Weird problems can drive you crazy.

Also check the threads over thread wires to make sure they aren't too loose.

???????

 

[Vicodan]

Rayjay, if I had a lathe, I wouldn't be using the barrel nut system.

 

[Toolbreaker]

Are you using a lug with an anti-rotation pin? If so, it could be holding the bottom of the lug off of the action face very slightly. A flashlight held between you & the action with the nut snugged hand-tight only would confirm this. If you're using a flat lug with no pin, is the lug set squarely at 6:00 upon tightening the nut? If the lug rotates far enough off center when the nut is tightened, the stock could be interfering with the right side of the lug & relieving some of the clamping force during firing & recoil. That last part is just me speculating, though.

 

[swd]

I'd buy a new nut and a tube of blue Locktite and go shoot.

 

[Vicodan]

The first action was pinned. The current action is not. I used shims in the action wrench to ensure the lug was square.

 

[Toolbreaker]

If everything's square & flush between the action/lug/nut, it could be the threads on the nut at max+ dimensions. Might try a single wrap of teflon tape on the threads between the barrel and nut. That might provide enough interference to keep the nut put.

 

[savagedasher]

I have had many and never have I had one come loose . They never get tighten to more then 70# to get them that tight you would have to have a action wrench . Larry

 

[rayjay]

It's definitely a perplexing issue.....

 

[kendog]

Two things come to mind. What is the origin of the barrel and how does that thread spec out, and what is the history of the receiver in question? Has anyone "improved" it by "truing" the threads and making them oversize? 9 times out of 10 that is a "fix" for where there is no problem. I have found Savages to have quite a bit of face run out, but even with .005 to .007 run out the factory barrels stay on.

 

[Vicodan]

It is a McGowan. As for the actions, they are untouched.

 

[jsn]

Who made the nut? How many threads are there on it?

 

[paperpuncher]

This problem has occurred with 2 different recs, so for the sake of conversation lets eliminate the rec as the potential problem. If we assume that the barrel manufacturer can cut a thread that is in spec that leaves the lug and the nut as potential problems with components. Have you carefully Mic'ed the lug to check for uniform thickness? Have you carefully inspected the nut how is the thread interface between the nut and barrel? How does the face of the nut look? Is the pin removed from the recoil lug? Could the pin be contacting the nut and not allowing the not to snug squarely on the lug. Just spittballin here