I just purchased a new M&P15 Sport (has the better 1 in 8 5R barrel). My first AR purchase to go along with the many M&P pistols I have and I can't wait until it arrives early next week. I am going to buy a Troy VTAC Alpha rail but I keep going back and forth between the 15" or the 13". Aside from the extra real estate and tiny bit of weight is there any real benefit to the extra 2"? I am not planning on putting to much on the rifle (Burris MTAC with FF III, Magpul AFG2, and flashlight......maybe something else but not really sure yet). It is more of a cosmetic / personal preference right? Thanks.

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

The longer rail will give you an increased sight radius for your iron sights, which should equate to better accuracy...if you are going to use irons.

Only until I can afford the optics that I want to put on the rifle. That makes sense though.

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

I have the 12" DD on mine. After playing with it I dont know if I would go any further out

Please excuse the pink pool noodle...its there for color contrast LOL...I find the 12" to work really well and I also like the afg better than the others I have tried and believe me I have tried a bunch.

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Grover Oathkeeper

This is my 12.37" Samson rail. I love it but would consider a 15" for my next build. Kinda' dig the rail going further up to the end of the barrel.

They are giving me a really good deal on the rail and there is only a $10 difference between the two. I am kind of leaning towards the 15".

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

I went through the entire M&P15 Pictures thread and only saw a couple of rifles with a 15" rail. Does anyone have pics of their M&P with a 15" rail on a 16" barrel? I would really appreciate it if you could post them so I can get a better look.

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

I have read with some interest the thread on rail size for a Sport. If I am not mistaken, the Sport has the 'A' frame front sight, so getting a rail for the longer sight radius would require both the removal of the original sight ,blocking of the gas tube and the additional expense of BUIS.

Not necessarily. There are drop in rail systems that will provide for a free float rail and provide a cut out for the front sight. This one for example.

Troy BattleRail Charlie|Rifle Accessories|Gun Upgrades|Troy Industries

So why not just save the money and put it toward the better optics ???

All the longer rail is doing is adding more weight,cost. The longer sight radius is much better for iron sights,but if you are going to replace iron anyway...???

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THIS WE'LL DEFEND ΜΟΛΩΝ ΛΑΒΕ

Mainly for a few reasons..........I really like the Troy VTAC and I am getting a very good deal on them. The Troy VTAC is barely any extra weight and I would like to hang a couple of things off of them and can't with the Sport handguard. Finally, I can't decide which optics I really want. There are tons of choices out there and I don't know what I really want yet.

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

You were almost exactly right, except for blocking of the gas tube. You would actually have to get either another gas block or cut down the front sight so that it will fit under the handguard. You have to have the gas system for the rifle to operate as anything other than a single shot.

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Grover Oathkeeper

That, my friends, is I stay away subjects I am not 100% sure of. If there is any doubt, ask my wife, she will tell how often I am wrong. Lol

You picked up an amazing rifle. I bought my sport and haven't regretted it and never will. It has everything you need, and nothing you don't. I have all mission first tactical furniture and the UTG pro carbine quad rail. Enjoy your purchase!

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