Trimming sprue

[Tenmile]

My Lyman molds leave a pretty small sprue, not like the old Dixie molds. I use soft lead and the short starter seems to flatten it out. If the sprue is dead up it should fly true. Voids probably have the most harmful effect.
Lynn

[TDM]

I use all Lee molds and as said they drop a pretty clean ball. If I do have a somewhat prominent sprue I load it sprue down. I’ve always done it that way, but most likely it makes little or no difference at 25-50 yards.

[Hungry Horse]

 At a trade gun shoot in Oregon I shot balls made in an old Dixie (hair straightener) mold, and cut off with side cutters, and then let them roll around in a big old baking soda can in the back of my truck all the way from central California to Cooz Bay. I outshot guys I had been playing second fiddle to for years with those balls.
 Chunk guns specifically built for those matches are often a lot more precision than the garden variety muzzleloader and might benefit from a coddled round ball, and then again maybe not.

Hungry Horse

[hudson]

I use Lee molds of late I have ignored the sprue placement seams to make no difference even way out there. As an experiment tried running some in my case cleaner took vary little time for that small flat spot to disappear. Tried some pretty bad ones with wrinkles same results looked just like Hornady makes you wonder how they make there, I have herd rumors.

[Dphariss]

Lee molds leave no sprue. Lyman molds leave a consistent sprue. It’s with bag molds that I have to fiddle with trimming.

But they leave a flat spot so it needs to be loaded “up”. I use Lyman and RCBS moulds and load sprue up. I may try a batch of 50-54 RBs in the tumbler one of these days.

[Dphariss]

Someone mentioned weight variations. I machined down through some cast bullets on the mill one day. Machined a board flat then epoxied a selection of bullets that looked good but weighed out from “nominal” some a little heavy to several grains light. Machined down  .010” at a time. As a result I don’t shoot projectiles that are more than 1 grain from nominal except for pistol bullets if I cast them. But this requires “knowing” the mould (how it likes to be filled and the temp) and being very consistent in using it. If I am casting “serious” bullets I never stop until the pot is empty or I have enough for the project. When I add metal to the pot I make them a separate lot for weight purposes. I guess I should do this with some RBs. But I just weigh them within 1 grain (the “heavies” are all good) but if more than one grain under they get remelted. You would be astounded the voids that can be in ball/bullet that is 1 grain or 1.5 gr under. And with a bullet twist, 16-20”, they will cause fliers. Very slow twist and short ranges. Maybe not so much. But testing this is a project I don’t need.

[Tenmile]

I find that most of my light ones come from the first dozen or so cast. I always throw them back because that is a pretty good sign of a void.  An old friend told me many years ago to eliminate all the variables you can and live with the rest.
Lynn

[Dphariss]

I find that most of my light ones come from the first dozen or so cast. I always throw them back because that is a pretty good sign of a void.  An old friend told me many years ago to eliminate all the variables you can and live with the rest.
Lynn

The cold mould etc will cause issues and I never keep the first 10 or so depending on the mould. But if you drive 1000 miles one way to a rifle match shooting maybe 250 300 rounds risking a flier or 3 or 10 is just silly. Anyone that does the checking I did by milling down through bullets will find things they did not expect even in the “good” weight bullets. Also the “heavies” are the only ones that are “perfect” absolutely solid, but they are a smaller percentage than the ones under weight. Exterior flaws will sometimes weigh “OK” or very close to it. Too long to explain here.