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View Full Version : Kudos to Mr. Boatright



Pete Wass
05-05-2009, 06:40 AM
Got my new PS Magazine yesterday and over breakfast this morning I read James Boatright's excelent article on Proper Barrel Tightening Torque. A very interesting read and some great imformation for we who have been languishing in the dark. ;) :)

JerrySharrett
05-05-2009, 06:57 AM
Got my new PS Magazine yesterday and over breakfast this morning I read James Boatright's excelent article on Proper Barrel Tightening Torque. A very interesting read and some great imformation for we who have been languishing in the dark. ;) :)
Pete, you can tighten your barrels to 35 ft/lb, great. Cecil Tucker and some of the other scope doctors will love you for that.

I tried the 35 ft/lb method on 3 different Pandas and barrels that have a perfect thread profile and square shoulder.

After tightening these barrels and actions to 35 ft/lb then I made a witness mark on each. Resetting the torque wrench to just 50 ft/lb I was able to move the barrels another 0.020" radially. Now then, was/is the threaded joint firmly loaded at 35 or even 50 ft/lbs??? Not in my engineering learnings it was and is still not!!

Pete Wass
05-05-2009, 07:00 AM
Pete, you can tighten your barrels to 35 ft/lb, great. Cecil Tucker and some of the other scope doctors will love you for that.

I tried the 35 ft/lb method on 3 different Pandas and barrels that have a perfect thread profile and square shoulder.

After tightening these barrels and actions to 35 ft/lb then I made a witness mark on each. Resetting the torque wrench to just 50 ft/lb I was able to move the barrels another 0.020" radially. Now then, was/is the threaded joint firmly loaded at 35 or even 50 ft/lbs??? Not in my engineering learnings it was and is still not!!

What do you say is the correct amount?

JerrySharrett
05-05-2009, 09:05 AM
What do you say is the correct amount?

There isn't probably a "correct amount" but 35 ft/lb sure isn't enough to suit me. Vaughn's 300 ft/lb may be a bit stiff too especially for custom actions that have good straight threads and a shoulder that is perpendicular to the axis of those threads.

I use somewhere between 100 and 150 ft/lb. That's me, do what you feel comfortable with. If that's 35 ft/lb,, have at it!!

On a previous thread I posted a chart that listed torques for the different class threads. Granted, these are Class fasteners but the amounts are way above 35 ft/lb. Your 416 SS barrel has a yield of about the same as a Class 7 fastener.

http://raskcycle.com/techtip/webdoc14.html

Pete Wass
05-05-2009, 11:11 AM
in his article was his stating that the chamber would stretch with more torque than 35. I have been using 100 FP for several years now. I don't know if it's right but I have a calibrated torque wrench which is limited to 100 fp. I simply want to know where I am at and I feel that 100 is not excessive nor is it too little.