AR Front Sight Housing R&R

[Lurch37]

Back in the day of the AWB I put together a Bushy AR-15, which meant buying a lower, a six position stock, and a 16 Heavy Barreled Flat Top upper, then of course putting it all together.

My question is now since the ban is over I would like install a front sight "housing" that has the bayonet lug. Is this something I can do at home and not screw anything up, or is this best left to a professional smithy. Can one send this off to Bushmaster to have them do it or would that be cost prohibitive?

I realize it's just cosmetic and have no real need to mount a bayonet, but still, it bugs me not to have the lug.

Thoughts?

 

[AMX]

I tried it once. I line the holes in the barrel up with a drill press, slid the front sight base on, used a laser to line the barrel and sights up then drilled and pinned it. After all that screwing around, it was still way off. Hopefully you're better at that kind of stuff than I am.

If you want to take the easy way out, YHM makes a bolt on front sight with bayo lug. If you don't get it right the first time, loosen it up and try it again.

 

[blume357]

I was just reading in an AR book and I thought the front

sight was basically glued on.... slipped on with pins but then glued to make it tight?

 

[Silentarmy]

I have never been able to swap a triangle front sight housing and have the pins align correctly! If you can get one pin set and then drill through the second hole to make the second pin fit then it should work and be aligned properly. The barrel finish under the housing is not black so the chances of the new set up looking funny till you refinish the entire thing is pretty high. I have yet to find any glue on the gas block when pulling one to do a railed block or low pro to allow the free float foreend to pass over it.

 

[Lurch37]

Army....are the sight housings pressed on and off or can one simply tap them off and of course back on? Getting the old pins out is no prob, but if I need a press then maybe I should ask my smithy if he could do it and how much.

 

[woodland]

I did one once. They are pretty tight, but I pulled the gas tube pin and knocked both sight pins out. Then I set up a heavy bench vise with wood blocks with heavy rags over them. I set it so the jaws were just barely bigger than the barrel diameter, and then with a rubber mallet I was able to drive the barrel out of the sight. Then pretty much reversed it all to reinstall it. With a little patience, and gentle finagling, it wasn't too hard to line up the pin holes again. I was putting the same sight back on, so I didn't have any issues with the finish lines no linig back up.

 

[Toten Kopf]

The holes in the front sight base are taper reamed, using a regular drill will just mess things up.

As stated above, the chances of having a non-original base match up to the existing holes drilled into the barrel is 1 in a million.

I would either go with the bolt-on style or remove the original sight base and weld/silver solder a lug on and refinish it.

 

[Denny Hansen]

Toten is correct in that that the pins on the FSB are taper pins. They need to be drifted out from left to right. Brownells has a polyethylene block that fits the FSB for the job.

Lining up the holes with the notches in the barrel should not be a problem if the parts are mil-spec, and have replaced several on new barrels myself. If using parts from tier 2 (and below) manufacturers, then yes, you may encounter problems.

Denny

 

[Lurch37]

Ok...I did see that block in the Brownells Catalog. I'm assuming when you say left to right your holding the rifle as you would when firing correct, as in the ejection port is on the right hand side? Also, where can a person buy just the lug to weld/silver solder on, or are you using a donor sight base and cutting the lug off?

Thanks

 

[Denny Hansen]

Lurch-
Affirm. To drive the pins out the rifle would be laying with dust cover down. I have never heard of just the lug being sold as it an integral portion of the front sight casting.