Marking a Mold Cavity

[Baron von Trollwhack]

I've always heard about that, but how it is it neatly done? I have one to do. Please advise me on this.

[fecmech]

If you simply take a sharp scribe and push the point into the mold somewhere near the point of the bullet it will leave a little dot which will show up on the bullet. In my 4 cavity moulds I leave one cavity unmarked, 1 dot in the next, 2dots in the next and 3 in the fourth cavity. Takes about 2 minutes and hurts nothing.

[dubber123]

I have a Lyman 2 cav. .44 wadcutter mold that has a "1" stamped in one cavity. I wonder if it's factory, as it's the smallest stamp I've ever seen, being less than 1/8" in heigth.

[NVcurmudgeon]

I have marked only one mould, a 314299 Lyman 2 cavity which is used in my best cast boolit shooter. It was marked with one punch mark in one cavity and two in the other, using a VERY sharp center punch. The reason for marking both cavities was to orient the boolits as well as segregating them. (After marking both cavities, it occurred to me that marking each cavity in a dfferent place on the ogive would have served just as well.) Anyway, it was easily done, no harm, and a valuable accuracy improving improvement gained. I don't think it would be worth bothering with for all moulds, but it was a real benefit for my one rifle that was capable of consistently staying within 2 MOA.

[STP]

My 311290 is prick punched in both cavities, one a bit higher on the ogive than the other. A bit redundant I thought. I have to look closely when I segregate by cavity.

[Baron von Trollwhack]

Thanks All. I think I will mark one cavity with a little sharp punch ,just below where a sizer nose punch/seating stem touches the ogive. I have to know, .7 grain of 72 is just too much cavity difference. BvT

[trk]

Thanks All. I think I will mark one cavity with a little sharp punch ,just below where a sizer nose punch/seating stem touches the ogive. I have to know, .7 grain of 72 is just too much cavity difference. BvT

Does the 0.7 grain difference between bullets make a difference in group size or in point of aim?

[Baron von Trollwhack]

I'm sure it will not change point of aim, that's what I do. Impact point?, group size?, I aim to find out. Its one thing to be shooting a H&G 38 gang mold wadcutter at 50 ft. indoors like in the old days, quite another to be trying to get that durn Marlin 25-20 consistently under an inch at 100. Did make a very nice beauty mark bump on the outboard nose' de' bullito though.