I've had a few requests to do a tutorial on how to replace the stacked leather handles on the M3, M4 & other knives with this type handle, so here goes!
Here's a "before" pic of the knife, a PAL M3:
First, remove the pommel. Best method I've found is to use a dremel with a small cutoff wheel & just "nip" the edges of the peened area back along the 4 sides enough to dive the blade out of the pommel. Don't grind the top of the peened end off or you wont have enough material to repeen & secure the pommel! It also helps to take the dremel or a file & remove just a bit of material from the blade handle where the pommel seats. usually just a few strokes with a file will be plenty to give just a bit extra for the repeening at the end.
Next remove the remnants of the old handle, if any remains & clean the blade handle. I usually knock any rust scale off with a file & run a bit of sandpaper on it. Once that is done, you are ready to start the new handle. There are knife supply places on the net & even a couple people selling the washers on Ebay, but I can't speak as to the quality of the leather. I'm picky about my leather so I make my own washers from saddle grade tanned hides I pick out myself. The hides I pick are approx 1/4" thick & very dense, not spongy, which eliminates alot of the compression issues associated with getting the handle tight. I cut the discs with a 1 1/8" round punch then with a hand punch make two holes then use a razor blade to make the slot.
Next, clamp the knife in a vise between 3 pieces of wood., one on each side of the blade & another underneath the tip (preferably a scrap of hardwood for the tip) & you are ready to start installing the washers. After experimenting with a few different methods, I've found it best to use thinner leather for the first couple of washers & cut to fit. This will help tremendously from slipping up later & sanding the finish off the guard.