Bullets to Small?

What you can also do,

Add in 4-6" of 1/8" - 95/5 solder to your full pot. Sometimes the added tin to WW will help out not only with mold fill out but with the sizes as well.

Just doing a brief look see at some referenced material, I thought I had noted a general guide to heat verses size. Well I know I read it somewhere but I can't find it now that I want too. Go figure. However, I did read the following though on this link,
Cast Bullet Notes

Tip: The size and weight of bullets of a given alloy will vary according to casting temperature. Higher temperatures will result in greater shrinkage as the bullet cools and produce a slightly smaller and lighter bullet than one cast of the same alloy at a lower temperature. Another thing and what I was actually looking for as well was the correlation of aging verses sizes. I have that noted here somewhere as well, in all of my "put it here so you can find it stuff". But as usual I can't find it when I actually need it.

The jest of it remains the same though, you might give the following a try.

Set aside say 20 or so randomly picked out of the bunch, maybe pull some of the AC and WC and keep them separated. Let them sit for a week, then measure them again. Then let them sit for another week and remeasure.

They are going to grow some, but how much is often simply a guess. I have found that sizing some of my bullets within two weeks works great, some not so good, just depends on the alloy.

As a rule, now I usually just pour up pot full, let them cool, and box them up until i need them. This way IF they are going to grow, which they usually do to some extent, they have done most of it and I don't have to worry about them doing the growing AFTER I sized them.

There is a multi paged discussion or two over on Castboolits that goes into great detail on this as well. IF you look around it should be easy to find, but I cannot remember which sub forum it was in.

Give the above a try first and see where that gets you. You might try checking them after a week first, then if they are still small give adding the tin a try. Or you might pour up half a pot of straight WW alloy then add in a 2-3" piece of solder stir well and pour the other half, then compare the two after cooling and then again after a week or two.

Sometimes with straight WW the temp is what matters most, sometimes it is the mold. Sort of like saying, hey just dump in 52grs of X powder and seat to Y OAL and it will shoot little clover leaf groups. It might work great in 3 guns out of a thousand, and the fellow who said it had one of those guns.

Hope this helps.

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