DIY mold making.

[Ironoxide]

Who here makes their own molds?

I recently made my first proper mold and I've learnt quite a few things in the process. If there is interest I'll describe it in detail. I would like to also hear any tips other people learnt when making their own bullet molds.

Here are few pictures.
The cutter before being heat treated:

And after the first test cut (what's left of it) :-(

Not to worry, enough of unhardened shank was left to machine another one. This time with better relief angles.

Here it is making a cut in the mold blocks.

Mold blocks were made with 7xxx grade aluminium rod. 2in diameter. Flats and other features were milled, surfaces were surface ground.

I borrowed a sprue plate from a Lyman mold. I initially planned to use lyman handles, but I ended up using Lees as they work better with long blocks like this one.

Here is the mold completed.

And during use

Results

Those bullets are 0.612 for an original rifle I have.

 

[deermanok]

Pretty nice work.

 

[Whitworth]

Well done

 

[Sidney Smith]

Nice work. I wish I knew how to operate a lathe.

 

[Notchy Bob]

Good work! I'll say that turned out well.

Notchy Bob

 

[BS]

Nice Work!

 

[ohio ramrod]

I make my own mini molds as well. I use a matched set of aluminum blocks with 1/8 guide pins to keep alignment .I use a radius tipped drill to drill the hole. Which will be the grooves of the mini, Then a grooving tool to cut the groves (which will be the O.D. of the actual mini) and a radius tipped stepped rod to form the hollow base of the mini. It is a lot of work but it allows me to make what ever style mini I want. By using different rods I can use the same blocks for different length mini's

 

[Ironoxide]

I make my own mini molds as well. I use a matched set of aluminum blocks with 1/8 guide pins to keep alignment .I use a radius tipped drill to drill the hole. Which will be the grooves of the mini, Then a grooving tool to cut the groves (which will be the O.D. of the actual mini) and a radius tipped stepped rod to form the hollow base of the mini. It is a lot of work but it allows me to make what ever style mini I want. By using different rods I can use the same blocks for different length mini's

Do you make your own blocks, or do you buy them somewhere? Lee used to sell "mold blanks", but I haven't seen them in stock for ages. Making the blocks was the longest part of the process. If I could get them ready made that would be great.

Another, question How do you size your mold cavities. I initially calculated based on heat expansion of aluminium and heat contraction of lead from solidifying temp that my cavity needs to be 3 thou larger than the target diameter (at 0.610 as target). I also received some advise on another forum to make it 3.5thou oversize. Both numbers were in the same ballpark. So I did make it 3.5 thou oversize. Unfortunately the bullet ended up 1.8thou oversized as cast :-(

It is not an end of the world. I can size it down if necessary or cut another mold. However I find it strange both my calculation and an advice of an experienced mold maker were that far off. Maybe it is due to my casting technique of pressurising the cavity with a ladle?

One interesting thing I learned is that one obtains a much nicer finish by cutting (7xxx) aluminium dry.

 

[zerosprk]

Nice lathe work. It is too bad the sizing wasn't what you wanted. I was interested in how well they shot for you.

 

[BS]

3.5 should have worked. round ball that size need to be .005 over.

Now you need a size die. Bigger is better.

 

[Gordoncourtney]

Some very nice work there. I make up moulds experimenting for my .36. Best is the 170g one in photo I also experimented using a 5/8” thread tap for the grease groves more a challenge and bit of fun as no chance of hunting with it in uk. Interesting subject many thanks

 

[Gordoncourtney]

Do you make your own blocks, or do you buy them somewhere? Lee used to sell "mold blanks", but I haven't seen them in stock for ages. Making the blocks was the longest part of the process. If I could get them ready made that would be great.

Another, question How do you size your mold cavities. I initially calculated based on heat expansion of aluminium and heat contraction of lead from solidifying temp that my cavity needs to be 3 thou larger than the target diameter (at 0.610 as target). I also received some advise on another forum to make it 3.5thou oversize. Both numbers were in the same ballpark. So I did make it 3.5 thou oversize. Unfortunately the bullet ended up 1.8thou oversized as cast :-(

It is not an end of the world. I can size it down if necessary or cut another mold. However I find it strange both my calculation and an advice of an experienced mold maker were that far off. Maybe it is due to my casting technique of pressurising the cavity with a ladle?

One interesting thing I learned is that one obtains a much nicer finish by cutting (7xxx) aluminium dry.

That's not so daft I have re used Lee blocks as they are so cheap, I bought a .375 block now redundant and made it into a .510 mould Only problem is getting the handles off, I ,made a right mess getting the handles off the last one I did , I have a mill but not tried milling the two halves separately I usually work more comfy on the little yellow East German lathe in the house side shed , piled up with gear. Ha ha my full side lathe is down the garden workshop bit miserable down there . Take care

 

[ohio ramrod]

I made my own blocks out of "cut offs" from where I worked as a tool and die maker. They used a lot of "two by two" square stock spacers on one of the production lines so they had a lot of end pieces left over. I machined them into matched sets of two. Then clamped them in a mill vice and drilled two 1/8 holes in opposite cornors , then used 1/8 brazing rod for the pins to keep them alighned, put the set in my lathe four jaw chuck, centering the parting line. I made mine a few thousands over size and then size them by running them through a sizing die I made. I'll try and take some pictures to post.

 

[Philip Lebow]

I'm an reformed tool and die guy (turned gunsmith!). I made some mold cherries the old way. Turned the profile of the bullet in A2 steel, and then milled the flutes in a dividing head in the mill. I have a vise that closes both jaws to the center. I was using Lyman blank iron blocks. Molds came out pretty well, but you have to take your time and use plenty of coolant. I had to make some .592 Minie balls to fit my Snider conversion.
They dropped OK at .591 with pure lead. Snider went from 2 1/2 feet at 25 yards, to about 4 inches at 50 yards.
I now think lathe bored is the way to go. Better centering of the mold cavity, and better chip removal clearance..
Follow Iron Oxides advice and technique. Good work!

 

[Ironoxide]

Gordoncourtney, nice. Those bullets must be for a very fast twist barrel being so long. Here is Poland we also can't hunt with black powder rifles :-( The law doesn't prohibit it, and some people used to few years ago (subject to minimum projectile energy requirements) until some beaurocrat in the government decided to publish "hunting guidelines" where black powder weapons are specifically forbidden. Ah, one of those years I'll go to Hungary for a muzzleloader hunt They have a special area for black powder and muzzleloader hunting. T This restriction is aspecially annoying because I'm right in a deer country. Two weeks or so I had two guys set up a tripod and shoot a deer 100m from my house.

Nice lathe work. It is too bad the sizing wasn't what you wanted. I was interested in how well they shot for you.

They are for an "unmentionable" (breech loader, Swedish made kammerlader for Navy model M1851). So range report will probably be in the English section of the svartkrutt.net forum in few weeks

Philip Lebow, Someone told me they make NOE molds on a mill with a cherry and they cut them one half at a time! I have to try that some time. I didn't know lyman sold blank blocks. I have to check out some local lyman distributors.

 

[Gordoncourtney]

You are right on bullet length never though of that at the time, just checked it and it's around 1 in 26 " to 1 in 28" I get different readings .... Need a better mop.......I was in a muzzle loading club, it kind of folded in 2013 when they lost their hut....I was to rejoin , but at 78 the police would not renew my certificates, all sorts of excuses , like I might shoot intruders, and our shooting lease had ended...so I can only shoot 12 ft lb air guns , and dream, they are fine knocks squirrels and rabbits heads off at 50 yards......France is generous on black powder guns and we were looking at a place there But what with Colvic and Brexit moving is a nightmare, and I cannot carry guns in my motor home when we visit, 180g .357 jacketed Sierra pistol bullets would be ideal with the base hollowed out reducing the weight to 140g in line with a .45 ball also at 140g better to pay for a decent hunt at some posh Chateau or Hungary like the handsome fellow shooting there on Utube.

U.K. Shooters will be hit again 6am big shooting in Plymouth 5 dead and English shooter shot him self dead, us gunny guys will pay dearly.

I am an engineer and always making bits and experiments for mates , I like rebuilding old flintlocks....I am 35 borne in 1943, Proud to be deaf with so much shooting over the years. Fortunately I only had my three shotguns confiscated. The remainder no licence needed as antiques...S58. but they must remain wall hangers ..yes it's a police state.

For those without a lathe you can make good moulds by drilling the two blocks then using a thread tap to make the grease groves, it works out quite well again this .625 bullet final sizing gets it perfect

I could ramble on for pages starting in 1963 but I had better close I wish you well.

 

[Elkhorse]

Where can I find a .58 mold like this?

 

[Gordoncourtney]

That seems to be a .500 pedersoli bullet there was a big picture of it in the old Kranks catalogue. Seems you need a friend with a lathe nothing else Kranks can offer. Life’s is tough

 

[Elkhorse]

That seems to be a .500 pedersoli bullet there was a big picture of it in the old Kranks catalogue. Seems you need a friend with a lathe nothing else Kranks can offer. Life’s is tough

I think you'll find that this is Thompson Center Hunter bullet. I have a mold in .50 exactly like this. I just need the .58 caliber. They sell the bullet at Track of the Wolf. I just like to make mine over a camp fire.

 

[ADK Bigfoot]

Where can I find a .58 mold like this?

PM Sent.

ADK Bigfoot