I have 2 dies that the vent hole has a little 'flash' around the inside of the hole where it enters the sizing die. I need to purchase a drill bit to open the hole up completely, will a cobalt drill bit of the appropriate size work on the metal a die is made of?

Thanks in advance--Don

In the past I have modified a few dies from various manufacturers. From the little experience I have the dies are not hardened steel per se. They are case hardened.....only the surface.....002" is hard the balance of material is relatively easy to machine. I would go with the cobalt....actually I would send the die back to wherever it came from and tell them to fix it.....unacceptable.

as long as the hole is already there you can likely clear it with using a simple wire....maybe a paper clip or other fine wire. Just push the burr out.

If you insist on drilling, any regular HSS drill will do as well as a cobalt drill. The cobalt is for somewhat higher surface footage and should drill more holes but is not necessarily harder than HSS.

thanks Vapo, that's what I was looking for.

If I wasn't so impatient,skb, you're right, I should probably send it back.

Thanks guys--Don

This sort of thing is easily corrected with a little patch of 400 grit emery cloth on a stick. A short piece of old cleaning rod with a slotted jag is perfect. Absent this, go down to Home Depot and purchase a brass toilet tank ball rod. Cut off a about a 6" section and cut a slot in the end with a hacksaw. To speed things up, chuck the rod in your handy drill motor. Do clean out the vent and push out the burr per above advice before running in the emery patch.

The fine emery will remove virtually no metal, and will not perceptibly change the dimensions of the die.

Follow up with cleaning patches or piece of old t-shirt in your stick, loaded with Flitz or Brasso or similar metal polish. Run it on your drill motor until it comes out of the die pitch black. You will now have a sizer that should require noticeably less force to use and one which will not mark even highly polished cases.

All this sounds like a lot of work, but it's really only a ten-minute job once the 'stick' is either found or made.

meplat, good info, it might be worth doing to some older dies, to just slick them up.

Thanks for the tip,

Regards--Don