FSB not drilled for taper pins

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[ARCHIVED THREAD] - FSB not drilled for taper pins

Posted: 1/20/2006 6:08:00 AM EDT

I would like to replace the FSB on my colt match target.
Bravo Co. sell USGI FSBs with bayo lug but they are not drilled for taper pins. How do I know where to drill? is this a difficult work?

Posted: 1/20/2006 6:56:41 AM EDT

[#1]

My local gunsmith did exactly that for me for $45. When I picked the rifle up he told me that he wouldn't do it again for that price.

You don't know where to drill and you probably need a drill press, along with the taper reamer...

I only needed 4 clicks on the rear sight to zero the rifle. That's why I paid the man. BSW

Posted: 1/20/2006 7:04:50 AM EDT

[#2]

precise measurements and a drill press should work

Posted: 1/20/2006 8:51:03 AM EDT

[#3]

Quoted:
precise measurements and a drill press should work

Emphasis on REALLY precise measurements

Posted: 1/20/2006 9:07:27 AM EDT

[#4]

Quoted:
Quoted:
precise measurements and a drill press should work

Emphasis on REALLY precise measurements

You forgot the Armorer! The VERY EXPERIENCED Armorer.

Posted: 1/20/2006 1:01:06 PM EDT

[#5]

I have done about 30 or so FSB conversions since the AWB took a well deserved dirt nap. After the first few i built some fixtures to do it the right way. One for measuring the old FSB and one for drilling the new one. I do the work in a Bridgeport mill with a DRO, even with the right equipment it is not an easy job to do. Drilling the holes is nothing, it's all the set up time. Everything has to be dead nuts at 90 deg.from vert. before you can even measure the old FSB. Then you have to do the same process to the new FSB before you can drill your holes, it's time consuming and there is no room for error. It's a job i would personally not attempt in a drill press. Let me know if i can be of any more help. PATRIOT ARMORY 07 FFL

Posted: 1/20/2006 2:51:55 PM EDT

[#6]

Quoted:
I have done about 30 or so FSB conversions since the AWB took a well deserved dirt nap. After the first few i built some fixtures to do it the right way. One for measuring the old FSB and one for drilling the new one. I do the work in a Bridgeport mill with a DRO, even with the right equipment it is not an easy job to do. Drilling the holes is nothing, it's all the set up time. Everything has to be dead nuts at 90 deg.from vert. before you can even measure the old FSB. Then you have to do the same process to the new FSB before you can drill your holes, it's time consuming and there is no room for error. It's a job i would personally not attempt in a drill press. Let me know if i can be of any more help. PATRIOT ARMORY 07 FFL

Yep. Not easy and not a DIY job. Some have gotten lucky with DIY. Most would not.

Definitely not worth the risk of trashing a barrel for a useless bayonet lug (to bring up a common reason to change a FSB), unless you ABSOLUTELY NEED that worthless bayonet lug.

Posted: 1/20/2006 6:41:33 PM EDT

[#7]

instead of drilling the bbl why not thread the existing holes on your front base. looking at and test sizing it . you can thread on side 8-32 and the other depending on mfg the same or if too tight lightly ream then run a bottoming tap. i did it (last night actually) and it works. of course i made 4 light indents on the bbl where the set screws touch giving it that extra grip. then red loc-tite the set screws. cost $0.98 for the set screws and my labor.

Posted: 1/20/2006 6:48:12 PM EDT

[#8]

Hey Mongo , your a 100% correct about bayonet lugs being useless (just like the U.N.) but you have to admit an AR does look better with one. PATRIOT ARMORY 07 FFL

Posted: 1/20/2006 7:04:23 PM EDT

[#9]

FSB'S with set screws work fine on a barrel that has not already been drilled for taper pins, if the barrel has been drilled you have to plug the holes to give the set screws something to seat against. Plugging the holes correctly is almost as labor intensive as drilling a new FSB for taper pins. PATRIOT ARMORY 07 FFL

Posted: 1/20/2006 8:39:58 PM EDT

[#10]

Armalite has a nice clamp-on FSB for $40.00 or so. No drilling.

Posted: 1/21/2006 2:42:02 AM EDT

[#11]

thank you very much for your replies!

looks like an hard work....I think I'll keep the original FSB without the bayo lug

thanks again

Posted: 1/21/2006 2:50:14 AM EDT

[#12]

Quoted:
Hey Mongo , your a 100% correct about bayonet lugs being useless (just like the U.N.) but you have to admit an AR does look better with one. PATRIOT ARMORY 07 FFL

While I realize many think that, I don't. It's a truely useless item to me and none of my rifles have one. YMMV.

Posted: 1/22/2006 11:27:29 PM EDT

[#13]

Quoted:

While I realize many think that, I don't. It's a truely useless item to me and none of my rifles have one. YMMV.

I'm with Mongo on this one...
Worthless
Only rifle I have with a lug is my M16 clone built with an original M16 upper from way back in the day.
I don't even own a bayonet for it.

Posted: 1/23/2006 3:35:56 PM EDT

[#14]

You could always drill from the bottom thread and put a set screw in, and use thread lock there and where the barrel contacts the FS. I have seen this alot on HP Match rifles and service match rifles

Posted: 1/23/2006 3:50:37 PM EDT

[#15]

The single set screw and loc-tite set up works great on a bench rifle or a service/ match rifle. But IMHO any rifle that might see some hard use should use taper pins. PATRIOT ARMORY 07 FFL

[ARCHIVED THREAD] - FSB not drilled for taper pins

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