Trim bottom of favorite mold - advice on how

[Low Budget Shooter]

Dear Cast Bullet Friends,

I hope some of you can advise me on how to accomplish something I've been planning to do.

My favorite bullet to shoot in 38 Special is the NOE 150 gr round nose. It has proven itself my most accurate bullet in many tests over the past few years.

The mold is a four-cavity brass model. It works great, but is heavy! My aging wrists start to hurt during a casting session.
A
n MP four-cavity brass mold I have is significantly lighter, being not as thick; I mean, not as tall from the bottom of the mold to the sprue plate. There is plenty of room on the NOE mold to trim material off the bottom, to make the mold lighter.

That's what I'm planning to do, but I have never done anything like that before.

Not being a machinist, is there a way for me to trim the bottom of that brass mold, while keeping it nice and flat, with common tools and a procedure that is not too advanced for a newbie?

I know that one very easy way to make this brass mold lighter is to buy an aluminum one from NOE :) I may yet do that, but I really like how the brass mold behaves, besides the weight.

Thank you,

LBS

[garandsrus]

I would think the only way to do it without power tools is a hacksaw and then files to smooth the cut. I have no idea how long it would take. Make sure you don’t cut off the alignment pins!

[country gent]

A lot depends on what tools you have on hand and skill level.
the lowest tool process to do this would be a hacksaw and file mark mould all around cut close then file and finish
A mill would be best and quickest.
Another is a drill press. simply drill holes through solid areas and blind holes where there are things. This will also allow you to work between cavities and alignment pins.

Keep in mind as you remove material mass goes down and heating and cooling will be affected. The drilled holes and or fining also increase surface area affecting this

[rintinglen]

A century ago, any gunsmith worth his salt would draw file just about anything he needed. Mills, lathes and power grinders were in the factory or perhaps in big cities. A couple of good files and patience will get you where you want to go.
You’re under house arrest anyway, so might as well do something constructive ��

[Low Budget Shooter]

Thanks, fellars!

[JimB..]

The easiest way is to sell it and buy the AL mold.

If you have a drill press maybe try a smooth forstner bit, freud makes inexpensiveones, and after carefully setting the depth stop start drilling away the excess. Use some wd40 as a lube to keep the brass from grabbing the bit and run the drill press at it’s slowest speed.

A bandsaw would be a good alternative, and a hacksaw followed by filing will go faster than you expect.

[Dragonheart]

I wouldn't do it! Brass is heavy, I absolutely agree. But I don't think cutting off a significant amount of brass to make a real difference is advisable. I would not think NOE would be using a block of the size they are if a block 2/3 the size worked equally as well. As you know brass molds need to run hot. A larger block will better retain heat. A larger block should have less of a chance of warping.
I am 72 and I have arthritis is my hands; I doubt if I am any stronger than you and I have about a dozen NOE 4 cavity brass molds. I run two molds simultaneously which increases my production as one mold is cooling while the other is filled. I would recommend setting up a rest to hold your mold when you pour. This is a photo of a mold rest I added to my RCBS Pro-Melt. You might also notice the added bottom plate which gives me more area to set my molds to cool. 261399261400


In addition I have a large heavy block of lead at the rear of my drop tray that I can rest the end of the mold on while tapping the sprue cutter.

[Low Budget Shooter]

Thanks for that good advice, DragonHeart!

[cabezaverde]

I use an upside down mini-bread loaf pan to rest the mold on when I am pouring. Just use a piece of pine under it to bring it up to height.

[root]

I wuldn't mess with it either but if you must.

A belt sander and aggressive grit will take it down fast and keep it pretty flat so long as you do your part.

Files will produce the best result if you don't have a end mill in your back pocket to whip out!

Remember anything you can ruin with a hand tool you can ruin two to three times as fast with a power tool.

Rich