If you need to persuade something into position but you don’t want to damage it, a lead hammer is the tool you need. Sure, a dead blow mallet can do the job, but nothing else can give you the same force-per-size ratio as lead — except possibly depleted uranium, though getting that shipped to your house could be tricky.
American Hammer’s lead hammers are made with a hollow steel shank that ends in a ring shape inside the head. As you use the hammer, the head fuses to the handle so it won’t loosen or break off. The other end of the shank attaches to a solid aluminum cast handle.
If you’re worried about what you do after you deform the head beyond use, American Hammer has you covered. They have a re-cast program where you can ship the hammer back to them and they’ll melt the head down and recast it for you, most times for $20 or less. If you’re on their delivery route, you can also trade your hammer for a recycled one, though the charges for that probably vary, since they don’t state a fixed price anywhere.
American Hammer sells lead hammers in sizes from 1 to 18 lbs. A 3 lb. hammer will run you $55 plus $10 shipping.