JB and heat

by Catoosa, Thursday, October 11, 2012, 09:38 (4428 days ago)

Some of you may have seen my most spectacular shot last Saturday, when I almost took out a rimfire swinger array about 30 yards downrange with the flashhider/front sight assembly from my Mini-14. Had to ask Jason to call a ceasefire while I went down and retrieved it. The flash hider and sight is none the worse for the experience, but the setscrew will NOT be trusted to retain it in the future. It appears thet some type of adhesive was also used on the bearing surface (the thing was on the gun when I got it) and the heat of firing a number of rounds caused the adhesive to fail.

Thinking of using J-B weld to reattach the flash hider. I know the stuff is strong, but does anyone have a feel for how J-B stands up to extreme heat? OR, does anyone have an alternate suggestion for a permanent reattach, short of having it silver soldered on?

I've seen this happen before on a mini - the entire assembly

by John K., Thursday, October 11, 2012, 11:06 (4428 days ago) @ Catoosa

took off downrange like a rocket.

Whatever else you do, make absolutely certain the ID of the flashider is aligned with the ID of the bore - flashider bullet strikes are hard on accuracy AND mounting arrangements.

lose the glue

by mike c, Friday, October 12, 2012, 16:07 (4427 days ago) @ John K.

Just drill a small detent right where the set screw tip contacts, (the set screw has already marked exactly where to drill) so the point of the set screw protrudes into the detent and you have a mechanical lock. This type of arraingment is called a dog point.

JB and heat

by Alfred John, Thursday, October 11, 2012, 12:10 (4428 days ago) @ Catoosa

I have found most epoxies will either break down, soften or begin to fail about +400 Degress F. There are some high temp. epoxies, might be able to research both J.B. and what else is out there. Good Luck on your effors. As mentioned make certain nothing is obstructing the bore from the flash hider. Good Luck.

I know of someone ..ahem.. who used JB weld and a nickel

by stonewalrus, Thursday, October 11, 2012, 12:24 (4428 days ago) @ Catoosa

To plug a hole on his pickup's muffler. Would have worked too if the nickel had not slid off the hole. JB weld can withstand some HOT temperatures.

I'd try Loctite 620 High Temp Bearing Mount

by JD, Western Washington, Thursday, October 11, 2012, 14:40 (4428 days ago) @ Catoosa

nm

and jb weld has ahigh heat version also:

by cable, Thursday, October 11, 2012, 16:37 (4428 days ago) @ JD

http://www.jbweld.com/product/j-b-highheat/


probably not as high heat rated as that loctite one though.

JB and heat

by John Meeker, Ask Mark S from Mich...about a poxy..., Thursday, October 11, 2012, 20:16 (4428 days ago) @ Catoosa

that he used on his snub 480 Ruger to attach a front sight. He uses it at work

I used Loctite 680

by Mark Stevenson, Thursday, October 11, 2012, 23:35 (4427 days ago) @ John Meeker

I would use the 620 Loctite for an AR or any other gun likely to get really hot.
The front sight on my 4 1/4" 480 SuperRed is held on by one screw and the 680 Loctite. So far it's held on nicely with no sign of separation.

Thanks, Y'all!

by Catoosa, Friday, October 12, 2012, 16:58 (4427 days ago) @ Catoosa

I'll try both the dog point and the high-temp Loctite.

RSS Feed of thread

powered by my little forum