Hi all, just bought an M&P 15 Sport, and would like to swap out handguards for the A1 style triangular type. PK firearms makes a carbine length set, but states that round handguard cap must be replaced with triangle model (set comes with this piece.) I was wondering if anyone has done this before? I have never done any armorer work on an AR before. I want to know if I am going to be in over my head as a novice.

Depends. You have to remove the flash suppressor, the tiny gas tube pin and the front sight post. If the fsp is taper pinned they can be a royal pain to remove. Then you have to reinstall everything.

This is what you'll need to do:

Brownells - Changing A Gas Block - YouTube

Whether or not you should try to do this is dependent on your mechanical aptitude.

S&W uses tapered roll pins that drive out in the opposite direction from every other gas block on the face of the planet. I forget which side to drive out from. Take a look at the pin. Start driving out from the side which has the smaller diameter exposed pin head.

I advise soaking the pins in some penetrating oil. I had to pound the heck out of my roll pins to get them out.

__________________
-John

Not difficult, but it take a bit of doing. The video pretty well says it all. You will probably want a few tools.

But if you're thinking of taking off the gas block/front sight post (and I would!), I would be tempted to make it into an A1 "dissipator".



Remove the front sight post gas block, and replace it with a low profile block that will fit under a set of handquards- you can find them for $30 or so. Then mount the front sight post with your triangle end cap at the front of the barrel, and put a full rifle length A1 handguard on it. To top it off, get a trident flash hider.



10x cooler than a carbine length handguard, for very little additional effort and expense. And the additional 6" of sight radius will make you more accurate with it.

I appreciate all of the advice. Doesn't seem too far out of reach, with the right tools. The dissipator option is not one I even thought of, but quite a cool option. I am glad I now have the right tools to make my decision. Thanks again!