Permanently attaching FS

[EmanP]

What is the best method for permanently attaching a FS to the end of the barrel to bring it up to legal requirements? What are the pro's and con's of the various methods?

[Jeff_M]

The two methods I am familiar with are the blind pin and weld or using 1200 degree silver solder.

With the pin and weld you will probably need to send it to a shop and have it done. The muzzle device is screwed on, and then a hole is drilled through the muzzle device into the threads and a pin in placed in the hole. The hole is then welded over and the surface is machined to match the profile of the muzzle device. In order to remove the muzzle device, it will need to be cut off and destroyed and then the treads need to be re-machined.

I would contact AR15 Barrels. His turn around is very fast and he only charges $20. http://www.ar15barrels.com/services.shtml

With the second method, you can do it your self. Go to Home Depot and buy a MAPP gas torch and then get some 1200 degree silver solder from a jeweler (about $30 to $40 for materials). Screw the muzzle device on with silver solder in the treads and heat it up with the torch until it is a deep cherry red. This method is quick and easy.

The disadvantages are that the heating of the barrel causes discoloration. A funny brown discoloring is left on the barrel. You could refinish the barrel when you are done. You can remove the muzzle device the same way by heating it up again if you need to swap muzzle devices or change out a free floating hand guard. However, you are left with a bunch of cruddy brown residue from the solder. Another problem is that you can supposedly get the muzzle device off with out heating it up if you torque hard enough. While 1200 degree solder technically meets the BATF requirements, being able to remove the muzzle device with a wrench and elbow grease kind of misses the point.

Hope that helps.

[Fireguy275]

Eman, for a recent upper I bought, I did the pin and weld myself based on an online tutorial that is posted on TOS. It came out nicely and took less than an hour, but does require than you have some equipment (drill press with a vice, welding set-up).
If your so inclined, we can link-up down near Tacoma and do the job in my friends shop.
I left the weld spot as is was so there's no doubt it's permanently attached.

[EmanP]

Thanks Fireguy and JMau. But if it's easier and seemingly faster and cheaper to silver solder it why wouldn't everyone be doing that? Either way, visually it's going to leave some evidence that one would have to blacken to remove. It seems like that would be a more popular method due to ease (you can do it yourself), time (you don't need to send it out and you just need to apply a little hear) and money (don't need to send it out which can be expensive).

[mike benedict]

blind pin and weld is 10-15 min. job if you are setup for it.
so most shops I know do it that way

Mike