Effect Of Barrel Nut Torque On Accuracy Question ..

[Opus Dei]

Has anyone ever compiled any empirical data on this? I've seen references to ~30 ft/lb on the low side to ~70 ft/lb on the high side of torque values-plus "snug 'n bump" torquing. Or does anyone think notable accuracy gains will be seen?

I realize each set of components is unique and results likely wouldn't be duplicated from one rifle to another. And I'm not in the middle of a project, but soon will rebarrel. Just looking for the collective experiences of those that have tried this. Thanks in advance.

[darkker]

Empiracal? No. Practical? perhaps.

I have tried everything from "hand snug" to 50-Ft-LBS by torque wrench. Neither affected the way the gun shot. The goal of torquing threads is to slightly "pull" them into interference, so that the items don't move. If the barrel is secured, I personally don't think it matters.

[nsaqam]

Empiracal? No. Practical? perhaps.

I have tried everything from "hand snug" to 50-Ft-LBS by torque wrench. Neither affected the way the gun shot. The goal of torquing threads is to slightly "pull" them into interference, so that the items don't move. If the barrel is secured, I personally don't think it matters.


Agreed.

[Opus Dei]

Pretty much what I figured. The exception I can think of is if something was out-of-spec; it could possibly exacerbate or alleviate accuracy.

[ellobo]

Some barrel nuts have uneven sufaces on the face that contacts the reciever. Place some medium grit paper on a very flat surface. Use a
"Magic Marker" to color that surface. Then face down on the paper give it a few swipes. Look to see if it only wiped a few spots clean. Keep doing it untill all the marker is gone and only clean metal remains. Wipe clean of any grit and you should be good to go.

El Lobo

[Opus Dei]

El Lobo-lapping the barrel nut makes sense, but are you working with a trued lug and receiver face?

[Gmac5]

Ther is a GREAT BOOK with a chapter on torque and much more .the title is RIFLE ACCURACY FACTS, by H .VAUGHN. Its well worth reading
Hope this Helps
Gary

[ellobo]

El Lobo-lapping the barrel nut makes sense, but are you working with a trued lug and receiver face?


Opus, I didnt do that to any T&Ted actions. I did it to see if I could get good contact enough to guarnetee I could tighten the nut with moderate enough torque to make sure it didn't loosen up without making it gorilla tight. Seems to work OK but then again, maybe it wouldnt move anyway. I do think though that it would benefit a T&Ted action. Can't hurt anything and easy enough to do. I have done it on three Savages with no ill effect.

El Lobo

[JimSheldon]

Hi gang,
Just joined the board. I have a left hand model 10 Tactical in .223 with a 24" heavy barrel mounted in a Choate "Ultimate Sniper" stock. I bought it used and was having problems getting it to feed from the magazine and on checking found that the point of the bullet was hitting the barrel to either side of the chamber depending on which side of the magazine it was coming from (staggered blind mag). Feeding singly, the rifle was turning in excellent groups. Well under MOA indoors @ 100 yards (3 shot group you could cover with the base of a .308 bullet.)

I suspected the barrel might have been set too far forward in the action so I borrowed a set of headspace gauges from a friend and sure enough, it would close on the no go and almost close on the field gauge. Bought myself a nut wrench and my own set of Forster headspace gauges. I was worried that the accuracy would be affected by fixing the headspace problem, but I needn't have worried. Not only did setting the headspace to the proper point fix the feeding problem, it didn't harm the accuracy at all. If anything, it may even have improved it slightly. My torque of the barrel nut consisted of snugging it up and smacking the barrel wrench soundly a few times with a dead blow shot filled plastic hammer. Of course, the action was clamped in a padded vise. Not the best procedure probably, but 100 rounds later, it still shoots sub MOA groups and the nut is still tight.

Jim Sheldon