Drill out a one cavity lee mold?

[Charlie Horse]

If I took a one-cavity, 30 caliber Lee mold and put it in my drill press and drilled it out to ~.358 would it give me good boolits?

[elk hunter]

Not likely.

Lee moulds are cheap. Why not buy what you need/want?

[country gent]

"Just drilling it out" wont give the new grease grooves or proper nose form/shape. Also the drill may not give a good finish to get good bullets.
Ideally a form cutter or cherry would be ground and ran in 1/2 dia at depth to form the new cavity, This gives the proper nose size and form along with the grease grooves.Grinding the cutter is the big job here.

If you have a special design you want to try recutting a set of blocks is the way to go. If you just want bullets to shoot buy the mould you want.

[ascast]

no I have a pile of junk molds that have been modified like this, all junk, don't work

[longbow]

If you are looking for a smooth boolit for powder coating then you could make a D-bit in the shape and diameter you want. I have made many for making push out moulds similar to the old Ideal Cylindrical Moulds and they work very well but I have not used one to ream out a split mould. Aslo, you would have to make sure you set up in the drill press very accurately or the bit may not stay on center and dead in line with the exisitng cavity. A drill press is not a milling machine! Using a d-bit in a lathe or lathe boring would have a much netter chance of success.

If you are looking for a paper patch boolit this should fine and you would make the cast boolit enough undersize that paper patching will increase diameter to groove diameter. If you want to lube the boolit then it should be cast somewhat undersize then knurled and dip lubed or tumble lubed.

Here is how to make a D-bit:

http://rvbprecision.com/shooting/shop-made-d-reamer-and-shop-made-casting-mold.html

Form tools can be used too if you want to cut lube grooves but for that you need a lathe.

Longbow

[Charlie Horse]

OK thanks. I've got a duplicate mold so I was wondering.

[Willbird]

There is also a factor between cavity size and bullet diameter based on the alloy used.

If you carefully measured the cavity in your existing mold and compared it to the bullets cast from it you would get an idea what that relationship is.

If you could drill and REAM the cavity and hit the desired size you might get something close enough to push through a lee sizer then powder coat.

[KCSO]

Drill undersize and then ream with a D reamer to finished bullet and it will then cast a good bullet. Go slow and carefull when reaming and use a good aluminum lubricant. I am currently working on a paper patch 420 mould for my 45-70. You do have to have a square set up and a vise for the drill press or mill and th base of the bullet has to be SQUARE!!!

[scattershot]

Not worth the effort, IMO. As others have said, just buy a new mold.

[Good Cheer]

A 9mm drill bit might work for 9.3x74R soft lead paper patch boolits.
I've thought about doing it but other possibilities have come to mind.

By the way, in the 70's I used a 3/8" bit to modify a Lee 9mm RN mold for use in a 1860 Colt. Worked extremely well. I rolled a bevel on the bases of the bullets using two small pieces of formica (using the back side of the pieces with texturing made to stick to adhesive).

[rusty marlin]

Can be done easily in a lathe with a 4 jaw chuck and boring tools.
Don't waste your time with a drill press. Not rigid enough.
Could be done on a mill with more time and effort than the lathe, but the lathe is the best option.

[Cris T]

Find a cheap reamer on eBay and use that instead of a drill. Turn the reamer by hand and be careful. You MIGHT end up with a mold you can use.

[725]

Although flammable, and hence dangerous, kerosene makes for a cutting agent with aluminum. I agree that if you just want another bullet, buy a mold. If on the other hand, as you have noted, you have some old molds to play around with, go for it. Not time wasted if you are doing what you want and like tinkering. Who knows, you may, indeed, find the better mouse trap! Have fun.

[turtlezx]

sell it ebay and but the correct 1

[john.k]

I set to and cut all the gas check grooves from all my iron molds.......First one was a 429 single cavity Lyman that I hardly ever use (too slow)......anyhoo ,soon discovered the slightest touch took it out to 435......next did all the rest of the two cavity ones,and they came out real nice using extreme care..........althought I thought later I should have taken out one of the 45s to 47 for my Martini.........wasnt worth setting them up again.....setup is what takes the time ,I got them running on under a tenth before cutting.

[GregLaROCHE]

If you are looking for a smooth boolit for powder coating then you could make a D-bit in the shape and diameter you want. I have made many for making push out moulds similar to the old Ideal Cylindrical Moulds and they work very well but I have not used one to ream out a split mould. Aslo, you would have to make sure you set up in the drill press very accurately or the bit may not stay on center and dead in line with the exisitng cavity. A drill press is not a milling machine! Using a d-bit in a lathe or lathe boring would have a much netter chance of success.

If you are looking for a paper patch boolit this should fine and you would make the cast boolit enough undersize that paper patching will increase diameter to groove diameter. If you want to lube the boolit then it should be cast somewhat undersize then knurled and dip lubed or tumble lubed.

Here is how to make a D-bit:

http://rvbprecision.com/shooting/shop-made-d-reamer-and-shop-made-casting-mold.html

Form tools can be used too if you want to cut lube grooves but for that you need a lathe.

Longbow

I’ve wondered before about drilling out a Lee mold. The article posted here is very interesting.