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kurbelgehause
July 25, 2007, 11:21
I consulted the postings here and found out that 120 ft. lbs. of torque is recommended for barrel torque. Is 120 lbs. considered to be nominal, minimum, or maximum? What is min/max for the barrel torque? Thanks for your help.

Ray

Radio
July 25, 2007, 15:33
The IMBEL factory often put on barrels with an excess of 200 ft-lbs. This is probably too much, and will allegedly only cause metal distortion and damage. 120 ft-lbs is considered to be "normal" but 90 would not be out of the question, either. The barrel should be tight to the receiver, but there's no need to "weld" it in there through mechanical force.

Note that in automotive applications, cylinder heads are frequently attached at 60 ft-lbs, and they are keeping the lid on scores and even hundreds of explosions per second. Rod caps are torqued as little as 45 ft-lbs, and these are containing tremendous inertial forces, preventing the piston from flying off into the cylinder head. Even the main bearing caps are quite often torqued to 70, 80, 90 ft-lbs, and these bolts are supporting the entire downward force of all the pistons acting upon the crankshaft.

I use my brute arm strength on an open-end wrench to barrel my receivers, so I don't have a "measure" of force, but they are on "tight". None have come off, or come loose, yet.

--Radio

dougjones31
July 25, 2007, 16:04
Heck yeah.....I have seen imbels that had been torqued so much that the threads were all screwed up and the barrel shoulder was mushroomed..........................hey, they were just trying to time the thing and it was a little out of spec........not any more!:shades:


Hand time it to 10:30 or 11:00 and then torque it to 12:00.....the actual torgue does not matter......it ain't gonna turn itself out of the receiver with 40 lbs of torque.

W.E.G.
July 25, 2007, 16:07
Originally posted by dougjones31
.....the actual torgue does not matter......it ain't gonna turn itself out of the receiver with 40 lbs of torque.

+1

kurbelgehause
July 26, 2007, 09:15
Thanks, gents!

Ray