Stubborn front sight won't budge

[guninhand]

I had decided to take the plunge and put a Pedersoli tang sight on my tang-less Browning Hi-wall in 45-70. In a rare stroke of wisdom, I figured I'd replace the dovetailed blade front sight with the globe sight first.

With the octagonal barrel secure and resting on softwood, no give to it, I hit the dovetailed blade front sight left to right, with a brass punch and wooden mallet. The blade sight didn't budge. I hit it again and again, harder. The tip of the brass punch started to peen back, but still no movement.

OTOH, the dovetailed open receiver sight came off eaisly. What can I do? I have Kroil but didn't apply any. I'm afraid I might damage the barrel where I'm hitting the sight so hard.

[Lloyd Smale]

bigger hammer but if you knew me youd hide every hammer in the county

[MtGun44]

A judicious application of heat to the barrel with a propane torch
may help, keep the sight cool by touching it with a wet sponge.
Try to cool (shrink or keep the same) the sight while warming
(expanding) the barrel.

If you have a friend that rivets aircraft, a flat pointed aircraft rivet
gun driving a brass punch can put extremely fast repetitive blows
much different in character than regular hammer blows. I have
seen this move stuff that nothing else would. Don't use a cheap
air chisel, the stroke is much longer, very different tool, even tho
they look and seem a lot alike. Ask my how I know this.

Bill

[Morgan Astorbilt]

I believe your problem is the wooden mallet, compounded by the block of wood you're supporting the barrel with. You've got shock absorbing material on both ends. Switch to a ball peen hammer, and if that doesn't work, support the barrel on something like a lead block(ingot). You can place a piece of paper between the block and the barrel, but lead usually won't mar the bluing.
Morgan

[Boz330]

Use the Kroil (great stuff), clamp the barrel in vice with leather covered jaws close to the sight and use a metal hammer and brass or aluminum punch. Like Morgan said the wood on both ends is to absorbent. Just went through this myself.

Bob

[Flinchrock]

I have seen tapered sight bases.

[redneckdan]

usually dovetails are roughed in with a mill cutter and then the fine fitting is done with the appropriate file. Usually resulting in a dovetail that is tapered.

[sturf]

could be a drop of solder under sight to keep it from moving

[guninhand]

It finally came off with no marring. I used a heavy ball peen hammer, kroil, birch wood rest, clamps and heated it with a heat gun for 4 min. Tks everyone.

[Mayor]

Glad to hear that the "bigger hammer" approach worked!