Anyone have experience swapping out their heavy UTG quad on their 15T? This is supposed to be a direct drop in using the existing standard barrel nut. But one concern, what are we considering standard? I like that it's lighter, FDE to go with my FDE furniture, and that it's modular without all the quads.

https://troyind.com/products/alpha-15-fde

this is standard?


Nut that is on the 15T:

The top pic is the standard barrel nut. The bottom pic is a barrel nut like many, but not all, free float tubes use. I've actually seen it called "free float barrel nut" in catalogs and vendor web pages.

So cypher, will the Alpha work on the 15T barrel nut? On all the installation videos I have seen, everyone is utilizing the nut on the top not the 15T nut.....

I think the nut on top is what you would need, but I don't have an Alpha rail... just been drooling over them... but JaPes does!

Many of the rails that I have seen that require a nut other than the standard one include the nut in the kit. You could always give Troy a buzz and see to be sure though.

Looks like the inside of that rail is cut where the teeth of the standard nut lock in with it...

The Troy alpha has a bunch of channels on the inner diameter that lines up with the "teeth" of the standard barrel nut at the 11 o'clock position. Once the rail and receive met, rotate the rail to 12 o'clock position and lock it down with three hex screws (that is if it is a newer Troy alpha rail). I installed the 13" inch, lately I wished I got the 15". Congrats on your upgrade. If you run a Q.D. sling check out the micro Q.D. sling mounts for that rail. Best way to go.

Cyphertext is faster...and with pics.

and of course after reading the Manual, S&W haven't updated their information and still have the old 15T utilizing the Troy rail.

But you came with real experience!

You wouldn't expect them to change the manual for such a "minor" difference, would you?

So it looks like the 15T nut is specific for Leapers UTG rails that are not slim or light. The only thing that will match up is the same ****** UTG rail. From the looks of their sight....they have a contract with S&W....sigh

Leapers, Inc. - Hunting/Shooting, Sporting Goods and Security Gear

what are you talking about?

Wu Who has a Troy rail that he has installed... first hand knowledge vs. me finding a pic.

He said my reply was faster, but his has more detail on how it actually locks in.

The troy Alpha rail clamps down to a stock mil-spec barrel nut via three screws. Easy-Peasy.

Wu-Who beat me to it.

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-John

Okay, I took off the rail, it's basically four bolts and this is what is left:





So you would have to remove the LP gas block and gas tube to remove the nut. Looks like I will be doing some basic gunsmithing.

I beat you both... but I did call out for your experience with this rail.

This is why the free float tube that I purchased from another forum member is still sitting in my parts box. I find something else to do every time I think about it.

Just a heads up for anyone removing their gas block.....there is a taper pin in addition to the set screws that you have to drive out. From what I have read it is a PITA, but if you lube it up and let it sit it will drive right out. It is taperd, so you have to tap it right to left. More to come!


https://www.youtube.com/watch?v=-gv1A9lh0MI

I'm curious. Is the single pin tapered as the two pins found on other M&P-15 rifles with an A2 front sight post?

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-John

Not sure....I would think so. I'm waiting on a new wrench and vise block tool to get shipped so I don't jack up my existing barrel nut and twist the upper and barrel. If you look at the taper pin, you can see that one end is slightly wider than the other, so obviously you would want to tap from the smaller end out with the fatter end protruding first.

I definitely can recommend spraying the pins on the gas block with PB Blaster or something like it. I tried to remove mine at first with out it and they wouldn't budge. I let them soak over night and they punched out with no problem. The barrel nut is a pain to remove though. I ended up using a set of vice grips and locking it around the barrel nut and using a hammer to tap on the vice grip to break it loose.
Here's my MW Industries Gen 2 SS on my 15T



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Good info! I would expect the barrel nut to be tough, since it is more thank likely torqued to 70 ft. lbs. I take it you didn't have an armorer's tool to remove the barrel nut? Anything else about the removal you would like to share? What barrel nut did you end up going with?

I just have a basic wrench for the castle nut and flash hider. The rail came with the barrel nut and wrench to put it on. Everything was really simple once I was able to get the pins free from the gas block.

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Pins? Besides the set screws and (1) taper pin, what else is there for the gas block?

The torque spec range for the barrel nut is a minimum of 30 ft-lbs to a maximum of 80 ft-lbs. Once timed properly, the nut will be closer to the minimum torque value than the maximum.

Once you've removed the muzzle device, muzzle device crush washer, gas block, and gas tube...

Removal: Place upper in the vise block clamp. Secure to vise. Use the armorer's tool. Insert a long handle socket wrench / breaker into the armorer's tool for more leverage. Push. It should come free.

Install: Set torque wrench to 30 ft-lbs. Tighten until you hear a click. Increase the torque wrench setting in increments of 5 ft-lbs until you get the barrel nut aligned to pass through the gas tube.

Tip: When reinstalling the gas block, use a pencil to mark the center line of the gas port vent. Mark the center line of the gas port on the gas block. Then all you have to do is match up the markings, set the screws, and tap the pin back into place.

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-John

Search YouTube for "AR-MPR" and you'll find a series of very informative videos.

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-John

Thanks JaPes....it looks straight forward enough. Just have to have the right tools. I'm actually looking at the MI key mod rail, it comes with nut, rail piece, nut wrench..... $189 for rifle length 15" rail.

Is that the 15"?

^^^ Go for it. The keymod handguards are narrow diameter lightweight goodness. Sweet stuff. The Alpha Rail is now "old tech".

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-John

Yeah it's 15"

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Alphas work on the standard barrel nut (the OP top picture). I have it on my 20 inch AR. It's a nice rail. Retains good and well made.

ImageUploadedByTapatalk1397339419.899589.jpg


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If all you're missing is a standard barrel nut with delta ring, I've got a couple sitting around. I'll also be more than happy to take that ****** free float rail off your hands.

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Freedom isn't free.

Oh yeah, one more thing.

Not all torque wrenches are the click type. Because I've calibrated thousands of torque wrenches, I don't trust the click type. So, I usually use the beam type at home. Both are fine for the barrel nut though because it's not a critical measurement.

The idea is to torque the barrel nut to 30ft/lbs. Then add torque until the holes line up so you can put the gas tube through. The lower the torque used, the better the accuracy will be. At least that's what they say. There should be no reason to even come close to the upper limit of the barrel nut.

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Freedom isn't free.

Thanks Rastoff.....I'm going with the MI 15" rail and it comes with all the hardware, barrel nut etc. This set up does not require a delta ring!

Yeah, I know it doesn't take the delta ring. I guess I'm just used to saying them together. I'll still take your old free float rail if you don't want it.

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Freedom isn't free.

Thanks for the tip. I'll need to add a beam type torque wrench to my tool chest.

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-John

Got bored waiting on new rail......turned out pretty good. $4.00 piss can