This may seem like a dumb question as I am new to AR's and don't know much about them. I am about to buy my first one and have decided on the M&P 15T. It has the features I want at a reasonable price and has good reviews. I think it will make a good entry level AR.
The only thing I don't like is that the quad rail is a bit large in diameter and I would rather have a slimmer grip. Yankee Hill Machine makes a style that I really like.
https://yhm.net/accessories/forearms...oat-ar-15.html
My question is will the YHM-5004A or YHM-5005 work on the M&P 15t ?
I appreciate any help I can get.

It'll work but you're going to need extra parts. Like the A2 fixed front sight/gas block will need to be swapped out with a low profile gas block. A new barrel nut, but I think most aftermarket handguards comes with a barrel nut. Removing those items can be a real pain.

Some Troy handguards use the existing barrel nut. There are also some models out there with a cutout for the A-2 sight if you want to keep it. Swapping it out with a low profile block is a snap on a new rifle since it wont be heat-seized to the barrel. YouTube is your friend when it comes to swapping out AR parts.

I just installed an adjustable gas block on one of mine. After I tuned it in the recoil/muzzle jump was reduced significantly. They run about $125 compared to $40-50 for a nonadjustable. I say it's an extra $75 well spent since you're gonna have it apart anyway.

This is the one I used. Apparently I paid too much.lolhttp://www.midwayusa.com/product/332...black-melonite

You have a couple of issues. the 15T has a free float handguard in which the front sight is mounted to the handguard and the gas block sits underneath it. It is a carbine length rifle with a carbine length gas system. So if you want the Yankee Hill handguard, you'll need the carbine length model the YHM-5000. The other 2 models won't fit since one is a mid length and one is a rifle length (again, 15T is a carbine length), they will be too long. Now the second issue is that, from what I read, the YHM-5000 is meant to be used with an A2 style front post (gasblock and sight) or a YHM front sight tower, neither of which the 15T has. There is a cutout in that handguard which allows those sight posts to stick up through it, but does not have a place to mount the front sight that comes with the 15T.

So here are you options as I see it (someone correct me if I'm wrong). Buy the YHM-5000 and replace the front gas block & sight with an A2 style to stick up through the handgaurd as intented. Second, buy the YHM-5000 and buy an optic and just remove the MBUS sights (metal sights that came with the 15T) altogether. The stock low profile gas block on the 15T should fit underneath the YHM-5000, then just deal with the empty hole in the top of the rail since nothing will be sticking out through it. Third, buy another free float rail that is thinner but allows mounting of the front sight on it, or lastly just leave the rifle stock and deal with the extra thickness.

Good luck, I would probably stick with the stock setup and give it a few hundred rounds to make sure you don't like it. If that's the case, then decide on the options you have. Good luck.

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Still carrying my S&W 642

The 15T does not have an A2 front sight. It already has a free float barrel, with a low profile gas block.

Why can't he put a longer free float tube on? They only attach at the barrel nut, so length of the gas system is irrelevant. As long as the tube doesn't extend further than the muzzle, there isn't an issue.

I don't see that the two models he asked about are cut out types. YHM-5004A or YHM-5005 look like they are full, top rail tubes without cutout.



Good advice.

The product description you have linked doesn't say if it uses a standard barrel nut or not. Since it does not specify, I would assume that it does. The 15T does not have a standard barrel nut, so you would have to change that.

However, since you are new to ARs, I probably wouldn't buy the 15T unless it was exactly what I wanted. You would be paying a premium for a free floated rail that you don't even like. Get a Sport or the OR, and buy ammo with the difference in cost. Once you shoot through that ammo, you would have an idea of what you want and could modify the Sport or the OR accordingly.

You are right, I guess there is no reason he couldn't. The rifle length is going to be really long and right up there near the flash suppressor though with the added 4".

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Still carrying my S&W 642

YHM has knowledgeable folks. Give them a ring a they'll answer whatever question you may have about their products.

Thanks for the replies guys. Still deciding............

I took the 'square-ness' out of my T's quad rail by adding Larue's "Index Clips" to it. The right angles don't disappear, but the Index clips makes the quad rail lots easier on ungloved hands. They are really helpful when reinstalling QD accesories back into the correct slots, too. I put them on my 15/22 also.

After shooting mine for a while I thunk seriously about changing out the quad rail on it but adding the clips changed my mind.

Well, that and the cost.

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AKA: "Strange Tamer"

You might take a look at Midwest Industries as well. They produce quality products.

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Even older, even crankier....