View Full Version : Barrel re-profile question
Could an a2 profile barrel with fixed sight/gas block be milled to more of an A1 profile in front of the gas block without removing the block?
I know it still be thicker under the gas block but would still remove a few ounces off the front of the barrel.
Why not just remove the FSB?
Practically, however, It's probably cheaper to just buy the barrel you want... factoring in machining and refinishing costs.
Why not just remove the FSB?
Practically, however, It's probably cheaper to just buy the barrel you want... factoring in machining and refinishing costs.
Isn't removing the FSB difficult on a BCM?
As for buying just what I want, I have another thread about that. Nobody of high-rep makes such a thing. (A1 barrel, fixed fsb, flat top receiver)
So I thought modifying an A2 fsb barrel might be the thing to do.
Isn't removing the FSB difficult on a BCM?
As for buying just what I want, I have another thread about that. Nobody of high-rep makes such a thing. (A1 barrel, fixed fsb, flat top receiver)
So I thought modifying an A2 fsb barrel might be the thing to do.
I don’t know the process, but I know someone that can do it for a good price if you’re looking for shops.
Sent from my iPhone using Tapatalk
https://www.bravocompanyusa.com/BCM-BFH-16-Mid-Length-Upper-Receiver-light-weight-p/bcm-urg-mid-16lw%20bfh.htm
Isn't removing the FSB difficult on a BCM?
Probably. But not impossible. I think Gunz used a large flat punch to get the initial bump on the taper pin.. then finishes with a regular taper pin punch. I have a taper pin punch that was concave on the tip. I got some Colt pins to move with that thing for member here. Some of my FSBs are just scratched up because I get lazy on my own guns and end up letting the punch slip/move.
Isn't removing the FSB difficult on a BCM?
As for buying just what I want, I have another thread about that. Nobody of high-rep makes such a thing. (A1 barrel, fixed fsb, flat top receiver)
So I thought modifying an A2 fsb barrel might be the thing to do.
Why are you soo against getting the Faxon barrel and have a FSB pinned on?
Why not just remove the FSB?
Practically, however, It's probably cheaper to just buy the barrel you want... factoring in machining and refinishing costs.
Yeah why not remove the FSB?
Id expect at minimum $100 from a machinist who knows what he’s doing, and with a barrel I wouldn’t go with a bargain shop.
Why not just remove the FSB?
Practically, however, It's probably cheaper to just buy the barrel you want... factoring in machining and refinishing costs.
If you think the FSB will cause you angst, just chop the FSB down and use it without pulling it.
wetidlerjr
06-22-18, 18:30
Probably. But not impossible. I think Gunz used a large flat punch to get the initial bump on the taper pin.. then finishes with a regular taper pin punch. I have a taper pin punch that was concave on the tip. I got some Colt pins to move with that thing for member here. Some of my FSBs are just scratched up because I get lazy on my own guns and end up letting the punch slip/move.
I have never had a problem removing a BCM FSB. I do let some Kroil soak in around the pins the day before I remove it. After that; easy-peasy! :)
wetidlerjr
06-22-18, 18:32
If you think the FSB will cause you angst, just chop the FSB down and use it without pulling it.
I agree and I've done that, too. Worked out great for me. :cool:
If you think the FSB will cause you angst, just chop the FSB down and use it without pulling it.
I think he is working on this project: https://www.m4carbine.net/showthread.php?207665-Lightweight-20-in-A3-w-pinned-front-sight-block
Thanks for the advice.
There are very few places you can ship a barrel and fsb and say, "drill holes through my barrel, pin this on and make sure it's perfectly straight".
And they'll probably tell you they'll try for a price but the result, ruined barrel, perfect job, or canted sight, is your problem and no refunds.
Thanks for the advice.
There are very few places you can ship a barrel and fsb and say, "drill holes through my barrel, pin this on and make sure it's perfectly straight".
And they'll probably tell you they'll try for a price but the result, ruined barrel, perfect job, or canted sight, is your problem and no refunds.
You haven't done much research. I'm not going to tell you where to go. Sounds like you are scared to dive in. Look at it this way.... If Colt can pull it off anybody can. It isn't rocket science.. Maybe give Marvin a call.
Thanks for the advice.
There are very few places you can ship a barrel and fsb and say, "drill holes through my barrel, pin this on and make sure it's perfectly straight".
And they'll probably tell you they'll try for a price but the result, ruined barrel, perfect job, or canted sight, is your problem and no refunds.
I said on the first page that I know of a shop, you can just PM me if you want an answer...
...but I repeat myself. Again...
Thanks for the advice, but excuses
https://www.bravocompanyusa.com/BCM-BFH-16-Mid-Length-Upper-Receiver-light-weight-p/bcm-urg-mid-16lw%20bfh.htm
https://www.bravocompanyusa.com/BCM-BFH-16-Mid-Length-Upper-Receiver-light-weight-p/bcm-urg-mid-16lw%20bfh.htm
I believe OP wants a 20” even though it wasnt specified in this thread.
Thanks for the advice.
There are very few places you can ship a barrel and fsb and say, "drill holes through my barrel, pin this on and make sure it's perfectly straight".
And they'll probably tell you they'll try for a price but the result, ruined barrel, perfect job, or canted sight, is your problem and no refunds.
Emphasis mine. Only way to know is to ask.
As for OP, i believe it depends on lathe, though you could remove fsb, but keep profile under it same for reinstall of same fsb with new taper pins.
I believe OP wants a 20” even though it wasnt specified in this thread.
Ah...
I'm sorry, yes, I'd like a 20 inch barrel.
I said on the first page that I know of a shop, you can just PM me if you want an answer...
I'm not willing to mail a several hundred dollar item to a guy/small shop out of state but I do appreciate you trying to help.
The FSB has to be removed to do any re-profiling of the barrel.
ADCO has no problems with this procedure.
Though I would just wait for the Brownells barrel to come back in stock.
I had ADCO re-profile a 308 AR barrel under the handguard numerous years ago. It turned out well, and I have no doubt they would be able to remove and re-install the FSB.
Their site probably shows their fee to remove and install it.
I'm not willing to mail a several hundred dollar item to a guy/small shop out of state but I do appreciate you trying to help.
This is limiting your options for no reason. If insured, whats the difference between sending to and buying from?
So you plan to have someone reprofile and refinish your barrel that you dont trust to remove and reinstall a fsb?
Edit: rainier arms might be ablebto do it if you dont trust ADCO or Marvin.
This is limiting your options for no reason. If insured, whats the difference between sending to and buying from?
So you plan to have someone reprofile and refinish your barrel that you dont trust to remove and reinstall a fsb?
Edit: rainier arms might be ablebto do it if you dont trust ADCO or Marvin.
No, I wouldn't send it to any guy/small shop for anything unless I've seen years of good feedback.
You mean insured shipping? I'd certainly pay for insured shipping.
I'll check adco. But as suggested, Brownell's is back ordered on the assembly I want. I've read the barrels they've been using are decent to excellent.
No, I wouldn't send it to any guy/small shop for anything unless I've seen years of good feedback.
You mean insured shipping? I'd certainly pay for insured shipping.
I'll check adco. But as suggested, Brownell's is back ordered on the assembly I want. I've read the barrels they've been using are decent to excellent.
Well you didn't ask for feedback, you just straight up said that you wouldn't do it.
I would get one of these and have a FSB addedhttps://www.brownells.com/rifle-parts/barrel-parts/rifle-barrels/ar-15-20-a1-rifle-barrel-1-7-stripped-prod97908.aspx.
Or wait for these to come back into stockhttps://www.brownells.com/rifle-parts/barrel-parts/rifle-barrels/ar-15-20-a1-rifle-barrel-1-7-assembly-prod97909.aspx.
Add this stripped upper w/out M4 rampshttps://aeroprecisionusa.com/ar15-stripped-upper-receiver-no-m4-feedramps.html
elephantrider
06-26-18, 16:08
Could an a2 profile barrel with fixed sight/gas block be milled to more of an A1 profile in front of the gas block without removing the block?
Answer: NO, not w/o removing the FSB.
If you want an A1 FSB barrel, your best bet is to buy an A1 barrel (Brownells) and have it drilled/taper reamed for a FSB. That is the shortest, and best bet to get what you want, no FSB removal/re-install involved, no re-profiling, no re-finishing.
I'd go with Marvin Pitts/Nefarious Arms. Small one-man shop who knows what he is doing. I've had him work on at least two barrels, excellent work each time.
Edit to Add: I have had Marvin reprofile a barrel, and re-parkerize/phosphate finish it. He did an excellent job, so he'd be my choice, whichever route you go, OP.
Thanks, guys I appreciate the help.
everready73
06-26-18, 20:07
I'm not willing to mail a several hundred dollar item to a guy/small shop out of state but I do appreciate you trying to help.
Pretty sure I know who wake recommended and he is one of the best in the biz. I have used a few well known shops and his is consistently the best. Service is great too. You really are limiting your options by not sending it somewhere
Dionysusigma
06-26-18, 23:06
Why not Fulton Armory? http://www.fulton-armory.com/barrelfa16m4gicontourcm1x9threadedchromelined-1-2.aspx Theirs is a 1:12 twist, though...
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.