lo pro gas blocks - modified FSB or aftermarket?

**rodder** · January 27th, 2010, 04:42 PM

I recently purchased a Troy MRF-MX 10" railed handguard to install on my CMMG 16" carbine. After a little google research I decided on a Daniel Defense low profile gas block:

Since placing the order I've been doing more research on gas block options and have found that the consensus seems to be that a cut down FSB reinstalled with the factory taper pins is the most reliable and secure way of running a LPGB. I have the tools and skill needed to modify my FSB but thought it would be nice to have the option of selling the f-marked FSB or returning the gun back to factory stock some day.

But after my most recent research I've become concerned about the reliability of an aftermarket clamp-on type LPGB. I figured with red loctite and a good tightening I shouldn't have to worry about the DD block coming loose but now I'm starting to have reservations. This is currently just a plinking gun, but once it's properly accessorized I've been considering using it for home defense. I also intend for it to be my main SHTF rifle so I can't be concerned about a GB failure.

So, my Qs, oh wise and all-knowing PAFOA members, are; should I be worried about an aftermarket clamp on-type LPGB and spend the time to hack down my FSB instead? and; If aftermarket is fine, which is better, set-screw (such as troy, larue, MI, etc) or clamp-on (DD, Vltor)?

Thanks!

**mojo** · January 27th, 2010, 07:40 PM

I think a little loctite should secure it enough so that you don't have to worry.

**CHEMICAL** · January 27th, 2010, 07:43 PM

I feel as long as you go with a reputable company that has been in the business for a while you should have no problem. generally their products wont have issues since the bugs have been worked out by now. I have seen stock ones cut down and longer rails run over top to give it a stunning look.

go with your gut to make yourself feel better, but I doubt you'll have any trouble with a reputable company's product.

**Legion_Prime** · January 27th, 2010, 08:24 PM

Personally I'd want to stake those fasteners rather than loctite them. I will never understand peoples obsession with the stuff. Securing those fasteners with red Loctite won't really do anything beyond gumming up the threads as red Loctite specifies heat as being needed for their removal. I hope I don't have to tell anyone here how hot a barrel gets after even half a magazine, cause if you've forgotten even once while on the range you don't forget anytime soon. VLTOR I believe conducted tests of their clamp on gas block and the torque actually rotated the barrel in the reciever before they could get their gas block to turn on the barrel. However if you absolutely positively have to be sure I'd recommend sending it out to ADCO to have the gas block properly mounted and pinned to the barrel.

**rodder** · January 28th, 2010, 11:55 AM

Originally Posted by Legion_Prime

Personally I'd want to stake those fasteners rather than loctite them. I will never understand peoples obsession with the stuff. Securing those fasteners with red Loctite won't really do anything beyond gumming up the threads as red Loctite specifies heat as being needed for their removal. I hope I don't have to tell anyone here how hot a barrel gets after even half a magazine, cause if you've forgotten even once while on the range you don't forget anytime soon. VLTOR I believe conducted tests of their clamp on gas block and the torque actually rotated the barrel in the reciever before they could get their gas block to turn on the barrel. However if you absolutely positively have to be sure I'd recommend sending it out to ADCO to have the gas block properly mounted and pinned to the barrel.

Stake the fasteners! Why didn't I think of that?!

Can anyone tell me the proper way to do that?

As for loctite, it's specified all the time for automotive applications (I have extensive experience with the stuff, hence the screen name), often on exhaust bolts. The red loctite is specifically for high-heat applications, yet they do say heat can be used to remove it... uhh, WTF?

Anyone know of a loctite alternative that isn't heat sensitive?

**Legion_Prime** · January 28th, 2010, 06:22 PM

Originally Posted by rodder

Stake the fasteners! Why didn't I think of that?!

Can anyone tell me the proper way to do that?

As for loctite, it's specified all the time for automotive applications (I have extensive experience with the stuff, hence the screen name), often on exhaust bolts. The red loctite is specifically for high-heat applications, yet they do say heat can be used to remove it... uhh, WTF?

Anyone know of a loctite alternative that isn't heat sensitive?

Staking (duh

) and safety wire. However I'm not sure that safety wire is really plausible in this case. You could always just lube the threads up with some JB Weld before tightening them . . . not recommending that, I'm just sayin is all.

**arrrrgh15** · January 28th, 2010, 06:49 PM

Rocksett.

used to mount threaded adaptors for suppressors....and stand up to the heat.

**Legion_Prime** · January 28th, 2010, 07:01 PM

Originally Posted by arrrrgh15

Rocksett.

used to mount threaded adaptors for suppressors....and stand up to the heat.

That's the stuff! We used to use that at the airfield for cylinders and all on the rotaries. I was even thinking of that just couldn't for the life of me remember what it was called, all I could think of was Lubriplate. Good call, and thanks for refreshing my memory.