Lee 6 Cavity .452 255RF, Some Small Bullets

[G. Freeman]

Hello Folks,

I'm a new caster and have used this 6 cavity mold 4 times and have cranked out around 300 usable bullets already (good fill and bases; bad ones have been culled out).

Most of the bullets come out at .452" to .4525". Some some at .453". However, I would get ~5 pcs of undersized bullets ~.451" every 100 bullets since the 1st day I started casting with this mold.

I'm using straight COWW ingots. Mold has been washed a couple of times and cavities thoroughly degreased.

Could it be that 1 hole is throwing small? Or could it be a lead flow issue (lacking tin)? I'm not sure how common this is with Lee.

My technique is still not very good. I try to get my bottom pour to directly pour into the sprue hole. I fill each cavity without connecting the sprues. When I try to connect the sprues, I just get one big mess and couldn't control the way I fill and move to the next cavity under the spout.

I'm making these bullets for my SW M-25 which have throats in the .453" range so I need the bullets be at least .452".

Could this be a defective mold?

Appreciate your input. Thanks in advance!

[Castaway]

I have the best luck when I let the flow hit the sprue as I fill the mould. Clip on wheel weights don’t need any tin added. You might want to run your pot a little hotter. If you can master a continuous movement from cavity to cavity as the lead continuously flows, you might have better consistency with your bullets. I suppose it’s possible to have one cavity throw an odd sized bullet (they all will to a certain extent) and would be interested in the results if you cast about 10 from each cavity and measured them.

[Mk42gunner]

Welcome aboard.

About the only long distance advice I can give is that it takes practice to get good at any manual skill. Casting boolits is a skill and can be learned, don't expect perfection right off the bat.

It may be a lead flow issue, but more likely it is your technique than a lack of tin. I too primarily cast with COWW with zero added tin.

When I fill a six cavity mold I normally start with the cavity farthest from my hand, fill it and when the sprue starts forming move to the next cavity. The normal flow of lead as the sprue forms is what connects it for me. A connected strip of six sprues is much easier to get off the sprue plate than six tiny sprues too.

If it were a small cavity, it stands to reason that 1/6 of your boolits would be small, not 5%.

The occasional large ones you get are probably from you holding the sprue cutter handle. It looks like a handle, making you think it needs to be held, but it ain't so.

Learning with a six cavity Lee mold is not the easiest thing to do, but if you can consistently run one, I think you can learn to run any mold easily. Its kind of like learning to swim in the middle of the ocean as opposed to in a waist deep swimming pool, i.e. not much safety margin.

Good Luck and keep after it, you will learn soon,

Robert

[G. Freeman]

Its kind of like learning to swim in the middle of the ocean as opposed to in a waist deep swimming pool, i.e. not much safety margin.

That is exactly how I felt. :-P

I've been a reloader for 30 yrs and make it in several calibers (pistol and rifle). Bullet casting is very different, and require a lot more focus and a kind of manual coordination I have never needed during the reloading process.

I really appreciate the input!

[Bazoo]

Are you measuring the bullets all the way around? Often bullets will be out of round slightly. Could be you're just measuring the small part occasionally and mostly measuring the big part on the others.

The way I do it is, get the mould hot and dropping good, then isolate the bullets from one good cast. Let them cool and measure them. I don't measure every bullet. When they go through the sizer, I can tell one is big or small, long as the sizer touches it I load it.

If your bore is .451 and you send a .451 bullet down it, it will be fine. If you have a constriction or other gun inconsistency such as too small of throats, no matter the size of the bullets you'll get leading.

[Mk42gunner]

Forgot to mention, if it ends up easier to cast by leaving just a tiny sprue; at the end you can connect the sprues by running a strip of alloy on them.

Yes this drains the pot faster, but I normally put the still hot sprues right back in the pot as I go. This way I don't have ten pounds of sprues and six pounds of boolits per pot full of alloy.

Robert