Re: Fixture/Jig to make homemade HP
If you have a drill press, making a fixture to drill out a bullet nose should be easy. Rip a piece of wood in half. Put both halves together in your drill-press vice. Drill a hole centered on the cut line, the diameter of the cartridge case you have in mind. Now, lightly sand the cut edges of both halves. Now, when you put the cartridge case in the hole, it will fit, but the two boards won't quite come together. Put this in your drill-press vice. Vice is holding the boards, boards are holding the cartridge. Center this under your press and drill hole.
You can do this for a cast bullet, but I would suggest you not do a FMJ. Here's why.
Visualize a cup. That's the bullet jacket. Fill the cup with lead. That's the bullet core. Now squeeze the cup into the shape of the bullet you want.
If you want a soft point bullet, you squeeze the cup so that the top of the cup comes together more, and some of the lead is squeezed out of the top of the cup. This is your soft bullet nose. Notice that the bottom of the cup is the bottom of the bullet.
If you want a FMJ, you squeeze the other end of the cup. The solid cup-bottom gets squeezed into the shape of the bullet nose. The lead core is made completely flat, and is now the bottom of the bullet.
When either of these are fired, the powder gases push on the bottom of the bullet. They are either pushing on the solid copper bottom, or on the lead, which is, in turn, pushing on the solid copper nose. Everything stays together.
If you drill the nose, or cut off the nose, of a FMJ, you have changed the cup into a cylinder. Now it is open at both ends. The powder gases CAN (notice, I said "can", not "will") push the bullet core out of the jacket, sending the core downrange and leaving the jacket in the barrel. You won't even know it, because everything sounded right, and you hit something. But the jacket is now a barrel obstruction, and firing the next round could cause a barrel burst.
This applies to a "Full Metal Jacket". There are many bullets out there now called "Total Copper Jacket", or variations on that name (Rainier, Berry, Speer sells some). They are copper plated over the lead, and drilling into them would be the same as drilling into pure lead. But you didn't mention the "copper-coated" bullets. You said FMJ.
Meddle not in the affairs of dragons, for thou art crunchy, and taste good with catsup - George of Lod, Year of Our Lord 297
I always take precautions.
Beware the Evil Bullet Fairies.