Alpha rail install

[ar15556]

I need some help in deciding which rail to use.
I'm looking at the Troy Alpha Rail, For an M4 flat top 16 inch carbine gas system.

I want to eliminate the FSB and use a .750 low profile gas block.

Would the 13 inch Aplha rail be the right one?

http://troyind.com/%20/rail-systemsaccessories/rails/ar15m16-rails/free-float-rails/troy-alpha-rail%C2%AE-13%E2%80%B3-no-sight

Then, use the M4 folding front battle sight?

[Sentaruu]

is the 13" alpha the right one for what? are you just trying to cover the gas block?

and yes a folding or fixed front sight post would work, whichever is your preference.

[ar15556]

is the 13" alpha the right one for what? are you just trying to cover the gas block?

and yes a folding or fixed front sight post would work, whichever is your preference.

I want to cover the gas block and provide a longer rail.
I want to make sure I get the right length for the 16 inch carbine system.

[Sentaruu]

then the 13 will work just fine.

[fallenromeo]

I want to cover the gas block and provide a longer rail.
I want to make sure I get the right length for the 16 inch carbine system.

So you could cover it with anything from a 7" up to 15" troy alpha on a 16" barrel.

There is no "right length" there is only what is right for you.

[mkmckinley]

The 13" Alpha is a good length for a 16" barrel. Any standard front sight will work including the one you mentioned. Also consider getting a pack of the squid grips while you're at it. I have a few Alpha handguards and did a little review here (https://www.m4carbine.net/showthread.php?t=103591)if you want a detailed idea on how it goes together. If you haven't worked on an AR before I highly recommend professional help.

[Zero Signal]

I want to eliminate the FSB and use a .750 low profile gas block.


Don't bother getting a gas block just shave down your FSB.

[Sentaruu]

Don't bother getting a gas block just shave down your FSB.

this is one option.

[ScottsBad]

Don't bother getting a gas block just shave down your FSB.

Yup, I second that. Definitely the way to go, gives you the most secure gas block possible, and you won't have open pin holes in the barrel. Search this site, there are some explanations and instructions around somewhere. Also, you can blue the cut down sight instead of painting it which is really easy.

BTW - Carbine length at about 7 inches, mid-length at about 9 inches. To cover go 9 inches and 11 inches respectively. To give yourself plenty of good rail space a 12 or 13 inch rail is an excellent choice on a 16inch barrel.

[Confed-rifleman]

My 11 inch alpha rail is exactly even with the end of the gas block on a mid-length. On a carbine gas length anything over 9 inches will be even with or beyond the end of the gas block.

[ar15556]

I need to remove the gas block to get the delta ring and other handguard positioning parts, don't I?

[Zero Signal]

I need to remove the gas block to get the delta ring and other handguard positioning parts, don't I?

Cut delta ring.
Have to unpin gas block to remove handguard cap usually. Don't have to totally take off barrel just slide forward.
Unless you can easily remove flash hider too. Then it will be a lot easier to grind down the fsb.
Check out YouTube there are a couple videos on this.

[Jmacken37]

Grind down the FSB. Much better option than a set screw low pro gas block.

Picture of 16" upper with 13" and 15" troy alpha (VTAC flavor) rails attached...

http://www.hunt101.com/data/500/medium/DSC06578.JPG

[Shoulderthinggoesup]

Another vote for shaving down you FSB. It is very easy to do and will be stronger than a pin on.

If you dont have a grinder or rotary tool you can get a nice one for 30$ http://www.amazon.com/Black-Decker-RTX-B-3-Speed-Rotary/dp/B000MUSLCC/ref=sr_1_1?ie=UTF8&qid=1365793834&sr=8-1&keywords=black+decker+rotary.

Spray it down with high temp (2k degrees) black engine paint and bake it on when you are finished.

[plouffedaddy]

Yup, I second that. Definitely the way to go, gives you the most secure gas block possible, and you won't have open pin holes in the barrel. Search this site, there are some explanations and instructions around somewhere. Also, you can blue the cut down sight instead of painting it which is really easy.

BTW - Carbine length at about 7 inches, mid-length at about 9 inches. To cover go 9 inches and 11 inches respectively. To give yourself plenty of good rail space a 12 or 13 inch rail is an excellent choice on a 16inch barrel.

Here's my how to video on shaving that sucker down:

http://www.youtube.com/watch?v=5sBqDpi-Cb4

[drx]

I shaved down a FSB and cut off the delta ring, and it wasn't anything too difficult, just time consuming. Make sure you are wearing eye protection and a face mask to protect yourself from inhaling the dust that will come off.

The HD cutoff wheels for Dremel tools work wonders, don't bother with anything from harbor freight (if it uses power, do not buy).

Honestly getting the taper pins out from the the fsb was the hardest part, and just because I underestimated how hard you have to smack them. It helps to have someone hold the upper down when you drive them out.

[Sentaruu]

HF isnt too horrible, the products are definately not for commercial use. but the occasional homeowner use is fine.

[ar15556]

I have a Jet Mill/Drill and a cordless Dremel.

Is it such a bad idea, to remove the FSB and use the lo pro block?

I might remove the FSB and mill it down.:confused:

[Travelingchild]

Is it such a bad idea, to remove the FSB and use the lo pro block?
... remove the FSB and mill it down.:confused:
Why not just protect the rest of the upper and mill it off while still attached to the barrel?

[NeoNeanderthal]

Why not just protect the rest of the upper and mill it off while still attached to the barrel?

This is exactly what i did. Wrap that sucker in a few old towels, a little duct tape and your good to go. Used an angle grinder for the gas block and a pair of snips for the delta ring. Spent 5 bucks for a can of high temp grill paint to treat the bare metal. Super easy- way easier then dicking with taper pins, especially for people with out FSB support blocks or the correct pins

[ar15556]

This is exactly what i did. Wrap that sucker in a few old towels, a little duct tape and your good to go. Used an angle grinder for the gas block and a pair of snips for the delta ring. Spent 5 bucks for a can of high temp grill paint to treat the bare metal. Super easy- way easier then dicking with taper pins, especially for people with out FSB support blocks or the correct pins

EoTech user:lol:

[ar15556]

How do you remove the front part of the handguard support?

[ar15556]

Why isn't this type of low profile gas block made with the corresponding pin holes?

http://troyind.com/%20/anew-products/troy-gas-block-2i-750-low-profile


Wouldn't that make reassembly easier?