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agent88
09-02-2014, 12:08 PM
I have a 16" govnt profile mid length barrel with a low profile gas block. I want to have a fsb pinned to it and run a moe handguard.

I know it would be easier to buy another barrel.

But would this even be possible?

If I could find someone who could mill the barrel for fsb pins I'm not sure who or how much that would cost. Is the .750 area of the barrel the same length on a low profile gas block barrel as a fsb barrel?

rero360
09-02-2014, 12:29 PM
It is possible, just a matter of buying the Fixed front sight post that has the same barrel channel as your barrel diameter, .750 in your case, and have someone with a mill drill the holes/slots for the taper pins. For someone who knows what they are doing, should take around an hour, including set-up and all that.

SFCRangerDoc
09-02-2014, 12:30 PM
talk to randall aka ar15barrels on here. He's down south and could bang that out for you in a short amount of time im sure. Cost i don't think would be that great.

http://www.ar15barrels.com/services.shtml

agent88
09-02-2014, 12:43 PM
talk to randall aka ar15barrels on here. He's down south and could bang that out for you in a short amount of time im sure. Cost i don't think would be that great.

http://www.ar15barrels.com/services.shtml

thanks... found this from ar15barrels.com:

Pin Virgin Front Sight Base to barrel $30
This service is to fixture your barrel and FSB in the mill and then drill and ream for standard 2/0 taper pins. The barrel and FSB must be new parts (un drilled) to use this service. If you are re-using a FSB or barrel that has been previously drilled before, the next service down is what you need. Please include taper pins with your FSB. We can also drill for and provide straight dowel pins if you specify in the comments area of the service form.


So I guess the gas block area is the same and a moe handguard will work this will work out great.

TheExiled
09-02-2014, 12:44 PM
I have a 16" govnt profile mid length barrel with a low profile gas block. I want to have a fsb pinned to it and run a moe handguard.

I know it would be easier to buy another barrel.

But would this even be possible?

If I could find someone who could mill the barrel for fsb pins I'm not sure who or how much that would cost. Is the .750 area of the barrel the same length on a low profile gas block barrel as a fsb barrel?

What gasblock is on there now? Some low pro's are pinned (or are cut down A2's) and you could swap it straight over. Obviously a FSB with set screws may not be what you are looking for, but it may be an option if it comes down to it

ar15barrels
09-04-2014, 1:53 AM
Some low pro's are pinned (or are cut down A2's) and you could swap it straight over.

You certainly can't just "swap" a cut down A2 fsb that was converted to a gas block over to another A2 gas block as no two A2 front sight bases are drilled in the same place.
Barrels that have front sight bases pinned to them were drilled and reamed as a mated pair.
There is NO standard location of where the taper pins go.
So, while you might look at a front sight tower and see holes in it, the likelyhood of you being able to slide that used front sight tower on to another barrel which already has notches in it is quite unlikely.

Look at how much variation there is between just these 3 different companies in how they install their front sight bases:

Bushmaster:
http://ar15barrels.com/tech/bushmaster-fsb-park.jpg

Colt:
http://ar15barrels.com/tech/colt-fsb-park.jpg

LMT:
http://ar15barrels.com/tech/lmt-fsb-park.jpg

If you look at the pictures, you can note that the LMT pin holes are completely IN the barrel, the bushmaster are mostly IN the barrel and the colt are halfway IN the barrel.

strongpoint
09-04-2014, 8:50 AM
Something like this (http://www.armalite.com/ItemForm.aspx?item=EU0240MPKIT) might be OP's simplest solution.

http://www.armalite.com/images/Medium%20Images%5Ceu0240mpkit.jpg

Junkie
09-04-2014, 10:50 AM
Except that's far too likely to get knocked free. It's worth the extra $30 to do it right.

FWIW, a few barrels only have 1" long gas block seats but that's uncommon.

Oceanbob
09-04-2014, 11:17 AM
Randell's the man......

OP, it always pays to do it right...:cool2:

strongpoint
09-04-2014, 11:24 AM
Except that's far too likely to get knocked free.

It's been reported (http://www.militarymorons.com/weapons/ar.optics2.html#torque) that a clamped FSB (when properly installed) can withstand enough torque to damage the receiver without losing alignment to the barrel.

Sunday
09-04-2014, 3:24 PM
Buy a whole complete upper and call it done. You need a spare upper anyway.

Grumpyoldretiredcop
09-04-2014, 3:56 PM
Something like this (http://www.armalite.com/ItemForm.aspx?item=EU0240MPKIT) might be OP's simplest solution.

http://www.armalite.com/images/Medium%20Images%5Ceu0240mpkit.jpg

I've been using one of these for a while on a beater AR. It doesn't shift.

ar15barrels
09-04-2014, 4:44 PM
FWIW, a few barrels only have 1" long gas block seats but that's uncommon.

Noveske is the primary maker of barrels with 1" long gas block seats.
I really have not run into 1" gas block seats on other brands of PRODUCTION barrels and I make a drawing for each type of AR barrel that comes through my shop:

http://ar15barrels.com/gfx/drawings.jpg

tanakasan
09-04-2014, 7:38 PM
^^That's the difference between hobbyist and pro!

Robert

Junkie
09-04-2014, 8:53 PM
Noveske is the primary maker of barrels with 1" long gas block seats.
I really have not run into 1" gas block seats on other brands of PRODUCTION barrels and I make a drawing for each type of AR barrel that comes through my shop:

http://ar15barrels.com/gfx/drawings.jpgWhich is why I said it was uncommon. Sounds like we agree.

My 5.45 barrel: http://ballisticadvantagellc.com/?product=5-45-14-5-hanson-midlength-1 has a 1" gas block seat. My recollection is that all of their Hanson profile barrels are that way, I'm some others are too. Don't know if you count them as production though.

ar15barrels
09-04-2014, 9:17 PM
My 5.45 barrel: http://ballisticadvantagellc.com/?product=5-45-14-5-hanson-midlength-1 has a 1" gas block seat. My recollection is that all of their Hanson profile barrels are that way, I'm some others are too. Don't know if you count them as production though.

I would classify ballistic advantage as a "short run" barrel company.
By production, I am talking about larger volume production like colt, armalite, bushmaster, daniel defense, noveske, bravo company and the likes.