Home Forums Hunting & Shooting AR and Tactical Rifles Installing New Yankee Hill Front Sight

I just got a set of sights from Yankee Hill Machine and can't figure out how to get the front sight installed.The directions say to knock out the 1/8 pins with a punch and then the 1/16 pin to remove the existing gas block.Install new sight and reuse 1/16 pin for gas block.I have bent 2 punches trying to knock out the 1/8 pins with 0 luck.They won't budge.The rifle is a Bushmaster flat top with out front sight.Any help would be appreciated.

Thanks in advance.

the pins are tapered that hold the gas block to the barrel. you got to drive them from the small end to the big end. i believe the smaller pi you mention is for the gas tube.

I have been trying to drive the 1/8 pins from the small side.Yes the smaller pin is the gas tube I think.I have been hitting these pins pretty hard and am concerned I might damage something.Should these be this hard to remove?

i've had some that were very hard to remove as the assembler put a locking agent on them. i'v never had a set i couln't remove with the right support block,punch and hammer though.

I've also had a few that were dang near impossible to remove. Shooter42 said it best, they are considerably easier to remove with the right tools. If I remember correctly, the pins are removed from left to right.

One problem with removing the pins is the fact they are rounded, which makes keeping the punch centered a little more difficult. I've actually used a centerpunch on a few to get a nice dimple going, which seemed to hold the punch a little better.

Good luck!

First off, I would not replace a pinned FSB/gas block and replace it with one that is retained by screws.

But if you insist, start with a big punch and a big hammer. Be sure and support the FSB and pound the crap out of it till it moves, then use the correct punch. Bushmaster pins are always difficult to remove.