Modifying a Lee mold

Butcherbill

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Has anyone here modified an aluminum Lee mold to get a heavier bullet, specifically by drilling out the cavity deeper and re profiling the nose?

I bought a Lee .401 145 SWC two cavity mold a few years back, I don’t shoot .40s&w nor do I shoot anything under 165gr in my 10mm. Would like a mold for some 200 or 220gr bullets and thought about trying it on one of the cavities on the 145gr mold I have, I’ve read of people doing this on cast boolits but figured I’d ask here as well.

In my digging through drill bit reference charts the closest bit size I found would be 10.20mm or .4016”

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You certainly CAN increase the bullet length but, IMO, NOT by “ drilling it out”. You need to make a cutter that represents the bullet you want and then “ream” out the mould. If you search “making bullet moulds” online you will find videos on how to make the cutter and make the mould.
 
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You certainly CAN increase the bullet length but, IMO, NOT by “ drilling it out”. You need to make a cutter that represents the bullet you want and then “tram” out the mould. If you search “making bullet moulds” online you will find videos on how to make the cutter and make the mould.
That’s what I recall reading over on cast boolits, making a reamer basically. Will have to do more research on it. 👍🏻
 
Bill, it depends on how much metal is at the bottom of your mold.

most molds are poured from the base, not all.

If there is enough metal in the nose end of your mold, you should be good to go.

Just be careful you drill it true to its axis.

One of the 50 cal "maxi ball" molds I had was modified in a similar fashion. It worked quite well and was drilled out properly.

Looked different from anything I've seen, other than on some of those European bullets with the "nipple" noses.

The angle on the cutting edges should work fine, as is.

Most molds are cut with a "cherry" type bit.

I've seen home made molds done on lathes, and they worked quite well. They were first drilled, then the grooves and ogive were cut with "inside cutting tools"

If you have a "lip" or "shoulder" at the base of the ogive, it will give you a "semi wadcutter" profile.
 
Bill, it depends on how much metal is at the bottom of your mold.

most molds are poured from the base, not all.

If there is enough metal in the nose end of your mold, you should be good to go.

Just be careful you drill it true to its axis.

One of the 50 cal "maxi ball" molds I had was modified in a similar fashion. It worked quite well and was drilled out properly.

Looked different from anything I've seen, other than on some of those European bullets with the "nipple" noses.

The angle on the cutting edges should work fine, as is.

Most molds are cut with a "cherry" type bit.

I've seen home made molds done on lathes, and they worked quite well. They were first drilled, then the grooves and ogive were cut with "inside cutting tools"

If you have a "lip" or "shoulder" at the base of the ogive, it will give you a "semi wadcutter" profile.
The link is basically how I had in mind to approach it, so I was on the right track by the looks of it. I was planning on setting it up in the mill and drilling the cavity out, it was the drill rod reamer/forming tool that I couldn’t remember.

I’ll have to try it on some scrap or one of the two cavities, worse case it becomes a single 145gr cavity mold lol. Ill have to see if I can find measurements for a 210-220gr .401 bullet, have 180-200gr I can compare as well and see if the existing mold block has the needed depth and material.

https://americanhandgunner.com/discover/breaking-the-mold-by-making-your-mold/
 
Nothing to add, but want to see where this goes.(y)
I think I have a good chance of pulling it off lol, by the looks of it there’s enough meat in the block. That’s a 200gr Campro for comparison, should be plenty of room to go 210-220gr. The oal difference between 180 and 200 bullets is small, so 200-220 seems feasible. I don’t need lube grooves, which will simplify things a touch.

Honestly doubt I’ll ever use a 145gr bullet in 10mm, have a bag of 165gr campro’s for when I want to plink with light bullets.
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I think I have a good chance of pulling it off lol, by the looks of it there’s enough meat in the block. That’s a 200gr Campro for comparison, should be plenty of room to go 210-220gr. The oal difference between 180 and 200 bullets is small, so 200-220 seems feasible. I don’t need lube grooves, which will simplify things a touch.

Honestly doubt I’ll ever use a 145gr bullet in 10mm, have a bag of 165gr campro’s for when I want to plink with light bullets.
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I'm no machinist, but length-wise there appears to be lots of room for you to play with there. I volunteer to test some free samples for quality assurance, accuracy, and like, other stuff I make up as I go along. .:ROFLMAO::ROFLMAO::ROFLMAO:
 
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