Hey everyone. I'm about to purchase a sport and I'm looking into all of the customization options available. Ive been looking all over the place and I'm wanting to know the size(s) that will work. I don't know if I like the short stock hand guard and would like some in the 9-12" range. Will longer ones work? Any advice from seasoned owners?

The parts that hold the front of the handguard are pinned in place on the barrel so yer pretty much stuck with the carbine length handguards.

Not to contradict you, but it's not that hard to install a low profile gas block and get a longer free float rail if you really want to go that route. I chose not to, but many have.

I personally chose the Knights Armament drop in quad rail and freaking love it. Solid as a rock and no changing out the gas block. Win,win.

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Still carrying my S&W 642

This. For a simple drop in hand guard or quad rail, you can only go with a carbine length. That will drop in right behind your front sight block. To go with a longer rail, you will have to cut down your front sight block or swap it out with a low profile block. Then, add a free float rail to cover it. So, the two types you will find will be drop in (you can only get carbine with your set up) or free float (you need a low profile gas block to go under it and you can get whatever length you want).

Its a sport, so keep it simple & don't over do it. But definitely carbine length handguard. Spend $ on ammo & shoot it.

I like a longer rail because i like to hold the rifle with my arm fully extended with a thumb over assisted grip. I also want room for a bipod. I started out with a troy 7" ff battle rail "quad rail" but when I decided to go 13" I opted for the troy ff alpha rail. Trying to keep the added weight to a minimum. Plus I have 5rails I can put anywhere theres a hole.
The low profile gas block and ff rails are fun to put on. Instructions can be found on youtube.

I also really like the longer rail. I opted for the 15" Troy VTAC and I am glad I did.

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M&P15 Sport,9Pro,9c,Shield9,45

I think I researched myself out of the sport. I'll probably go with the 15 OR. I also noticed it had no dust cover or forward assist. Would the low profile gas system change void the warranty?

How important is a dust cover? The only rifles I own that have them are ARs. I have a LOT of rifles and shotguns that have no dust covers at all. The bolts are exposed 100% of the time. They get no dirtier and stay no cleaner than my ARs do when they are all shot.

FWIW, I've seen more people get a cartridge stuck in the chamber by pounding on the forward assist than anything else. It can almost be a hobby unto itself....watching folks at the range, with reloads and ARs....bolt doesn't quite close...SMACK that forward assist, several times (if once is good, twice is better) and really jam that out of spec cartridge into the chamber.

Nothing wrong with the OR....nothing wrong with the Sport. I have an OR....mostly because the Sport was not made when I bought it. Else, I would probably own a Sport.

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Stu

Not sure how that would impact the warranty. I'd call S&W to find out. I swapped mine out but figure if I have any issues, I'd figure it out by tweaking the rifle. I have an OR because the Sport I went to get sold about 10 minutes before I got to my LGS. I had planned on a longer rail and it would have been so much easier to cut down the FSB than swap the OR gas block.

What changed your mind to head you to the OR. Great rifle, but it is the same carbine length handguard config as the sport, so if you want a longer rail you have to change the gas block on the OR too....and what Billyjack said, it's tougher to swap.

Just curious, that's all.

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Still carrying my S&W 642

Well, I think you make excellent points... I guess I can't really justify an extra $300 for the OR and it's not even range ready (NO SIGHTS). Unless anyone else has a reason why the forward assist and dust cover would be worth the extra $$!

Have many friends who has owned ARs for many years & never once use the fa. & unless your going to be in a dessert for days or weeks don't ever think you will need a dust cover either. I own a sport, no fa, no dust cover, no problems...

It's real simple. Take the OR and add sights, now your difference is closer (if not over) $400. If the FA and dust cover are not important, the decision is easy. Many of us have been down the same road and come to the same conclusion, so you are not alone.

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Still carrying my S&W 642