Marking a cavity ?

[cabezaverde]

What seems to be the best way to put a permanent mark in one of the cavities of a 2 cavity mold. Bullet is a swc if that matters.

[NVcurmudgeon]

I have successfully used marks from a very sharp center punch to indicate the separate cavities. If you wish to orient the boolits, both cavities need to be marked. This can be done by marking the two cavities with one and two punch marks, or by marking the two cavities in different locations with one mark. I make the punch marks as far away from the joint in the blocks as I can get.

[Junior1942]

I used a nail and put a scratch on the nose. The photo shows the scratch on the two bullets on the left, and the scratch marked for indexing on the two bullets on the right.

http://www.castbullet.com/shooting/photos/accu01.jpg

[BruceB]

I've only wanted to mark cavities in a few moulds over the years, but I used a triangular needle file to cut a very small notch right at the extreme forward end of the cavity on just one of the blocks, dead-on centerline of the bullet.

For instance, my RCBS 270-130 mould drops bullets which are precisely one grain different in weight, on average, so I marked one cavity as above. This allows instant identification of which cavity the bullet came from, even in loaded ammo, and because the mark is on-centerline, it makes no difference to the "balance" of the bullet. The tiny file notch leaves a miniscule "tit" of bullet metal, centered on the nose. This marking method is useable on moulds for any bullet shape.

[fecmech]

I used a sharp scribe on my Lyman 4 cav 358429, leaving 1 cavity clear and pressing gently on the front face of the nose in the other cavities, 1,2,3 dots. It leaves tiny bumps on the front of the meplat, easily seen for loading or shooting. Nick

[cabezaverde]

The mold is a Lyman Keith 358 170 grain swc. The cavities cast about 2 grains different from each other. I just haven't decided if I am being too picky with a pistol bullet 2 grains apart.

[fecmech]

Cab--That was why I marked my 4 cav cause I had roughly a 3 grain spread. I don't think the weight matters as much as the bullets are just enough different to make the groups a little larger. Also the group enlargement does not matter much till about 50 yds (I'm talking pistols here). Now if I'm trying a different load or something new I just look at the noses and pick all from the same cavity for whatever I'm trying new. OTOH I was gifted a "matched pair" of H&G rn 158 gr. 4 cavs and when things were warmed up and humming I did not have much more than a 2 gr spread between all 8 cavities. I now use the "Buce B" method with only one of the H&G 4 bangers now. Nick

[buck1]

The mold is a Lyman Keith 358 170 grain swc. The cavities cast about 2 grains different from each other. I just haven't decided if I am being too picky with a pistol bullet 2 grains apart.

By all means mark it. The trick is to use a sharp center punch with--A LIGHT BLOW on the nose-- from a small tap hammer. A small ding is all that is needed. Just a dimple. I mark all mine.
Load them all as normal, but when a great group is needed grab all the same marks.
It dosent hurt anything if lightly done , and can help quite a lot when top groups are needed. I knocked 1.5" off my groups at 100 yd with my .308.
I didnt want to mark my first one,but I now mark all mine. BUT JUST A LIGHT DIMPLE!!! ...Buck