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Have a M&p 15 want to add a rail

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March 27, 2020, 10:36 AM
mhughes
Have a M&p 15 want to add a rail
I have the M&p 15 optics ready ar15, I want to add a free float rail. I know I need a low profile gas block, and take off the rail gas block that’s in there. Would I then remove the ring that holds my Magpul handguard on?

Or is it just as easy and cost effective to buy a assembled barreled upper?
March 27, 2020, 12:32 PM
smpsmp
You will need a solid vise, and a block to hold the upper (I like geisseles reaction rod) to remove the barrel nut. That will let you remove the delta ring. You'll also need this to install the new barrel nut that works with the handguard of your choosing and a torque wrench (torque 3 times to 35 ft pounds then align for gas tube if the barrel nut requires you to do so).

I'm a fan of geisseles forends and they come with a gas block that is pre drilled so you can pin the block. Wait for holidays as they go on sale for 25 to 35 percent off.

If you don't want to do any of this then it can be cost effective to buy a new barreled upper. But it's easy to do and you then have the tools to change barrels and whatever else you want to.

You'll also need a new crush washer for your flash hider (if yours uses a crush washer currently).
March 27, 2020, 12:50 PM
RHINOWSO
There are drop in F/F handguard options from DD and Centurion. The FSB will remain, but the rail will be free floated around it.

You have to cut off the Delta ring and some other pieces for some of them, but it's pretty straightforward
March 27, 2020, 09:17 PM
1gkek
I like Midwest Industries hand guards and they come with a barrel nut and wrench. You'll have to get your own gas block though. As smpsmp said, it's easy to do.
March 27, 2020, 09:46 PM
Chowser
You can shave down your fsb too and use it as a gas block



Not minority enough!
April 04, 2020, 12:34 PM
mhughes
Ordered a Troy 13 mlok free float and a .750 gas block. The Troy uses the mil spec barrel nut.

Can I reuse the gas tube?

Forgot to get a crush washer for flash hider, how important is that?
April 04, 2020, 03:51 PM
hrcjon
sure, but since its such a cheap part and annoying to deal with why not change it while its already out?


“So in war, the way is to avoid what is strong, and strike at what is weak.”
April 05, 2020, 04:01 PM
mhughes
quote:
Originally posted by hrcjon:
sure, but since its such a cheap part and annoying to deal with why not change it while its already out?


Ordered after I broke a punch trying to get the pin out of the original