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Posted: 2/25/2015 1:56:44 AM EDT
| Is 15 ft/lbs enough? I spent way more time than I should have trying to get my muzzle brake timed properly and finally got it just right at 15 ft/lbs. After rocksett will that be sturdy enough as a suppressor mount or should I go back to the drawing board with the shims to figure out a setup that's timed with more torque? AT 15 ft/lbs I'm not able to unscrew the mount by hand, but that isn't saying too much. |
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Quoted:
^^^^^ This. I would say north of 90* after contacting the crush washer is probably a good rule of thumb to ensure adequate friction to prevent loosening as vibration and thermodynamics do their thing. He's using the muzzle device for a suppressor so there is no crush washer. OP - what can are you using? Some mounts have different specs depending on the manufacturer. I use YHM and IIRC they quote 20-30 ft/lbs without rocksett. |
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He's using the muzzle device for a suppressor so there is no crush washer. Ah, missed that. No crush washer, I'd personally about double the torque you have, go 30-35 ft lbs. Remember that the harder the material, the less it stretches/galls/otherwise deforms at a given torque/pressure. When you use shims instead of a crush washer, you're losing the friction provided by the constant tension (memory) of the deformed aluminum. Same concept behind lug nuts on solid alloy wheels needing higher torque than those affixing steel wheels that have a gap between hub surface and wheel surface near the stud: 
Having said that, I don't use anaerobic compounds on barrel threads; if you're using Rocksett or something similar, as mentioned, hand tight is likely enough once it sets. |
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Quoted:
He's using the muzzle device for a suppressor so there is no crush washer. OP - what can are you using? Some mounts have different specs depending on the manufacturer. I use YHM and IIRC they quote 20-30 ft/lbs without rocksett. Quoted:
Quoted:
^^^^^ This. I would say north of 90* after contacting the crush washer is probably a good rule of thumb to ensure adequate friction to prevent loosening as vibration and thermodynamics do their thing. He's using the muzzle device for a suppressor so there is no crush washer. OP - what can are you using? Some mounts have different specs depending on the manufacturer. I use YHM and IIRC they quote 20-30 ft/lbs without rocksett. I'm using SilecerCo Specwar cans, just picked them up today. It's a shame, I got the cans before I even finished up the rifle builds. Oh well, the last of the parts should be arriving this week and the lowers should be back from the engraver next week so hopefully I'll be hurling some lead quietly downrange next weekend. |
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