New to this site so I'm looking for some help. I'm a bullet maker and want to make my own bullet swage dies. I made some d shaped reamers of a2 and tried to cut some bullet dies yesterday in some (annealed) d2 round. The reamers I made didn't cut very good, made a very rough cut in the d2. Could it just be the way d2 cuts, should I be using a steel like a6 that machines better or maybe its my reamers? Reamers are basic d shaped with a little releaf on the cutting edge.
Please help,
George

Sometimes reamers cut smooth, sometimes not, could depend on material, coolant, how well you keep chips out, how much stock is in the hole initially
how sharp is the reamer etc.....

That being said - in a nutshell, a useless answer to you......

You may want to think about other options as well i.e. jig grinding after heat treat, wire edm after heat treat etc...

Just on a side note: When I was a kid, I needed some .44 caliber round balls
for a muzzle loader and had a bunch of .50 caliber laying around that I had no use for.... just so happened a 1/2 dia. typical off the shelf nut (i think that was the size) had a .437 hole thru it with nice sharp edges all the way down (the threads)- made a pretty nifty swedge die and they worked!