Lyman H & I dies

[hanover67]

I size my cast bullets with Lyman H & I resizing/lube dies in an RCBS LAM II lubrisizer. Resizing .38 caliber 148gr wadcutters, I recently noticed that the sized bullets were .003" smaller in diameter that the size stamped on the die. Foe example, a .356" die produced bullets of .353" and a .358" die resulted in
.355" bullets. I'm using Jake's Ceresin Scarlet, a hard lube that requires heat. My lead is range scrap that measures a BHN of 14.3 with a Lee hardness tester. The bullets drop from my Lyman 35863 mold at .358 X .359" - they are not round...

I thought maybe I had a bad die, but not 3 in a row. I asked if anyone on another forum had experienced this problem and why it might be occurring. No one had an explanation for the problem (other than to suggest I was guilty of "operator error", couldn't measure diameter properly, etc).

The solution to the problem may be to hone out the .358" die with crocus cloth wrapped around a dowel until I get bullets of the desired diameter.

I always assumed that bullets would be sized as indicated on the die itself. Also, This issue is not as pronounced with either smaller (.313") or larger
(.430") sizing dies.

Does any of this sound familiar?

[BigBronco]

Curious, since you are heating the lubesizer, Do you get the same results when it is cold?

[Cheep]

What instrument are you using to measure? You might use something else and compare.