Crazy idea check???

Tell me if this is a bad idea or not. We all know that some of these group buys can take a long time to come together to where we have a mold in our hands.
I want another HP mold for my new 41magnum and found a 4C GC mold. Personally speaking, I dont find it necessary to use GCs in my handguns.
So I was thinking of ordering the GC mold and then taking it to work and reaming out the GC area of the mold.
Im a machinist and tool and die maker by trade so the operation doesnt seem to be a big deal.
Is reaming the GC area out a “nuts-o” idea?

been done lots of times. may need to redo the spru plate screw hole. you can order molds individually from noe, mihec, and others, you do not need to wait for a group buy.

No ,I don't think it's nutzo. I have read on Cast Boolits that many have done this, and being a machinist, you should have no problem doing it. Remove the gas check shank area rather than reducing the top of then mold. I think reducing the height of the mold would reduce the bullet weight

Have never done it myself, but have seen many times where folks have milled off part of the bottom of mold to eliminate gas check shoulder or simply to make a lighter bullet. What you are doing is opening up the bottom of the mold to full bullet body diameter, which would be a little trickier than just milling off the bottom section, but you obviously have the equipment and the skill.

My real reason for posting is I am trying to figure out why doing this might require redoing the mold sprue plate hole, as rancher suggested. Not a criticism, just trying to understand.

Thanks,

Jackpine

[QUOTE=

My real reason for posting is I am trying to figure out why doing this might require redoing the mold sprue plate hole, as rancher suggested. Not a criticism, just trying to understand.

Thanks,

Jackpine[/QUOTE]

If you mill off the bottom of the mould, thus eliminating the gas check shank and making the boolit lighter, you may have to re-drill and tap the sprue plate hole deeper to get enuf purchase on the sprue plate screw.

If you simply mill out the gas check shank, thus making the boolit slightly heavier, you do not have to change the sprue plate hole.
Jackpine--does that help?

Its not crazy. If you have the skills and tooling it should work out fine. I've had a few bevel base molds that I would have liked to do this with.

That is what I thought. OP was not talking about milling off, but just opening up, so could not understand why rethread of screw. Thanks.

If you have the correct Mill bit, it is very easy.
Ranch Dog offered that service on his molds when he was selling 6 cav Lee customs in his designs...I have one 41 mag 155gr RF mold from him that had the GC shank Milled for PB.

If this mold is alum, a person handy with hand tools, can use an exacto knife to remove most of the material, then hone/polish the remaining material down to size with a wood dowel and varying grits of sandpaper. I haven't tried this, but may give it a go some day...I have read others having doing this successfully.

PS, 6 years ago, I wrecked my first mold (a Lee Bator) by trying to remove a GC shank using a chinese drill bit in a chinese drill press. BUT in that vary moment before I went too deep, I think I could have been successful, LOL.

With your background, it might take you a half hour once you think about it for a while. I have a Lee mold that had a bevel bottom on the bullet, and I drilled/reamed the bevel off. For me set up was the longest part with the clamps, centering the mold cavity, etc. I drilled the bevel out then reamed the bullet base to area final specs.. After the bullet is sized, any mold modifications/machining marks cannot be seen...

Tom at Accurate will cut a mold of your specifications in the material and cavity count of your chosing. But if cost is the concern, then it looks to be a doable and interesting project for one who has the tooling and wherewithal.

I have often thought about it too. I haven’t gotten around to it, maybe because I’m not a machinest and don’t have access to a machine shop. If I did it I would be forced to use a drill press and wooden dowel with sandpaper.

What I don’t understand is, if you remove anything you are going to end up with a heavier not lighter boolit. Right? You don’t remove the shank of the boolit. Just the part of the mold that makes the indent for the GC. Right?

I just want to have confirmation I am understanding what I think I understand, before I screw something up.

Remember the lube groove area in front of check. You know how to find center, it's on you now!

I've done it successfully both by shortening the mold and by reaming the GC area. and I'm NOT a machinist, so it should be easy for you.

I have done several with a chinese bit in a chinese press. The key is making sure run-out is at a minimum, you have a good machinist vice and accurate depth. As you know a flute is better than a bit.

I did two Lee 38-55 double cavity molds with the bevel base, I used a wood dowel split with a hacksaw blade and 60 grit sandpaper to start then real fine grit to finish it up, worked great. I did all this with a Chinese drill press.

Thanks guys, now its just a matter of ordering the mold. Unfortunately, the new 41mag didnt show to be very accurate today with the boolit I do have for it.

I have done them with a reamer when the right size is available better is a true boring head in the mill a sharp short bit and a few thou at a time makes a truly round base and very nice finish. If you have digital read out then indicate each cavity in to 0,0,0 and make note of the numbers bore the first one then use the numbers and bore the rest. A reamers 34* cutting edge may get to the band and change it if depth is controlled close. I did one in the jig grinder got a guy also.