Pulling the nose of the hammer back is easy, but requires heat. A small tip, say a #0 on an oxy/acetylene set up is perfect, but I have used mappgas also.
You can't compress metal, only stretch it, so figure out where it needs to stretch the most and put the bulk of your heat on that area. Make it work like a hinge. If you need to bend the nose rearward, put most of the heat just under the thumb spur, on that V shape at the rear of the hammer. Get that area glowing red, then try to carry the red across the crease to the front. Heat the opposite side also, then finish by putting extra heat on that back V area. You're looking for bright red, especially where it needs to stretch to most. Don't try to bend by pulling on the spur, you'll just bend the spur. Try putting a small crecent wrench over the nose and bend down. If you get too much heat on the nose, the recess will collapse. Practice positioning the wrench so you don't get uncoordinated and take too long after the torch is pulled away. Only put enough of the hammer in a vice as you need to hold it tightly, vices suck out heat quickly. You may not feel it bend, so check after you pull down, a little at a time.
When you think you got it right, install the hammer and check the fit with a cap. When you get enough parts in place to drop the hammer, see if it will pop a cap with the first hit. If not, you may need to alter the inside of the recess. When it's perfect, file and sand away all your tool marks
That's all I can think of. Good luck. Bill
