I am going to be putting a FF rail on my Bushy,and since the FSB has to come off,I figured I will just go ahead and get a new FSB with a bayo lug.I live in MA,and my Bushy was originally bought as a ban safe weapon.I have since got a pre-ban lower.

FSB's are not in the Bushy catalog,but the part # is in the schematic.So I just got off the phone with Bushmaster,to check availability and price of part # 9349054FSHA (Front sight) Customer Service replied "We don't sell those". So I said how does one go about aquiring a FSB ? Customer Svc said "You have to buy a whole BBL"

WTF!!!

I am relatively new to the world of AR's,besides my time in the Infantry,but this doesn't make sense.Bushmaster sells everything else for the weapon,but not this.Why??!!! I have a $250 Gift Certificate from Bushy,and so far there isn't one thing I want on there in that price range..I figured this certificate would offset the out of pocket costs for my upgrades,boy was I wrong.Bushmaster carries all the ARMS's stuff,but they can't special order a #40 LSP BUIS.

So I guess my last part of this rant is where do I get a FSB for my Bushy M4 profile BBL ?

Quoted: I am relatively new to the world of AR's,besides my time in the Infantry,but this doesn't make sense.Bushmaster sells everything else for the weapon,but not this.Why??!!!

Because the FSB and the barrel are drilled as a single unit.  If you try to swap the FSB, it is very likely that the taper pins won't fit properly, and the FSB will come out crooked and will not be indexed properly.  Thus, you would have to crank in excessive windage correction on your rear sight.  It is not even worth trying.

The barrel two taper pin channels are drilled with the FSB index in place (read no two are alike), and unlike say a set of hand guards, you would need to drill the FSP taper pin holes in the FSB to try and match the current barrel taper pin channels.  Due to this, Bushmaster does not sell standard FSB's.

If you want to try and take this project on, you can buy a FSB from one of the other suppliers, but be forewarned, it's not a fun project trying to get the new FSB taper pin holes drilled the same as the old one.

Yeah, they wouldn't sell me one either, but I did see a guy on the EE with them for ~$35.

Find a gunsmith who know ARs. My local smith exchanged FSBs (new F FSB) for $45. Given the headache, I feel it was money well spent.

BTW, I only had to change the rear sight 5 clicks to get it to zero. My guy knows ARs. BSW

It isn't worth the trouble.

Quoted: It isn't worth the trouble.

+1

Unless you have a mill and all the other tools to do the job.

I'm sure that if you sent the upper
to BM, they will install the FSB at
no charge. I stumbled onto this
FSB/Tapered Pin PITA thing just
a few days ago. Good Luck.

Johnny C!

YHM makes a fold down front sight with lug that bolts on. This will go on in 10 minutes or less.

Quoted: It isn't worth the trouble.

+1M.

once you get it off, put something else on that doesn't rely on "custom fit" with the barrel.
see below for one idea, the BM 3 or 4 rail gas block (on the black carbine).  
you can also go with a Larue low profile gas block (on the desert tan rifle) but that means you need a forearm rail to mount your BUIS.

ar-jedi

Quoted: It isn't worth the trouble.

That's what he said when I picked it up. He won't be doing the next one for $45 neither. BSW

Quoted: YHM makes a fold down front sight with lug that bolts on. This will go on in 10 minutes or less.

+1

I installed one of these last week and it's right on the nut.

I used one of those laser sighting tools that are built inside a shell case.  I loaded the laser in the chamber and tightened down the sight when it lined up.  Easy as pie.

Thanks for the advice guys,shows how little I know.I thought you just line that FSB up and put it on the BBL.At least know I know why BM doesn't sell just the FSB.

Also,I never planned to do this work myself,though one day I would like to learn.Most likely I will be going with the flip up /bayo lug/gas block set up.

If you don't plan on doing this yourself you can send your upper to ADCO Firearms, and they'll charge $85 to replace your FSB with a no-ban one, and that price includes the no-ban FSB.

Quoted: If you don't plan on doing this yourself you can send your upper to ADCO Firearms, and they'll charge $85 to replace your FSB with a no-ban one, and that price includes the no-ban FSB.

Yet another option.Thanks for making my decision even more complicated..LOL Everytime I convince myself what I am going to do,another option pops up This is the most logical choice for me,since I know he does good work.

Thanks Falls.

Quoted: I'm sure that if you sent the upper to BM, they will install the FSB at no charge. I stumbled onto this FSB/Tapered Pin PITA thing just a few days ago. Good Luck. Johnny C!

Bushmaster won't, aleady tried it.

On Tuesday, November 1, 2005, at 12:11 PM, [email protected] wrote:

Each bbl has the sight base drilled and pinned for that bbl . we cant match one up. You can get this.

http://www.bushmaster.com/shopping/bmas/yhm-9370k.asp

look around there are a few other options.

I put on a PRI FSB after the bastards at Bushmaster would not fix a canted FSB-






I really have no need for a bayo lug...The PRI is a soild, but expensive, FSB...better built than the YHM one.