Cast and size for RD311165

[popper]

3rd casting session with this mould (3x3) and now I have a problem with wide variation in dropped size. Some come out .316, some .312. 50/50 Pb/#2 with some shot added on this session, AC. Parting lines show but no fins. I was only pouring the PB holes, next to the handles. Large ones STICK in the .310 sizer, like pound them back out, the shot shouldn't make them super hard right away or cause swelling. No gaps in the blocks, that I could see while it was cooling. Previous sessions they dropped right size. I used a spent case to presort, if the nose fit in the case it's a keeper. Saves having to mic 500 or so. Poured a bunch of .40 and they were right size. I'll try another session next week to see if I did something wrong but I'm confused (or inexperienced) at this point.

[runfiverun]

look inside the mold for flecks of lead, especially around the pins.
keep your thumb off the sprue plate handle.

[stubshaft]

You could be varying your grip on the mold while casting.

The shot may make it harder immediately depending on the amount that you used. Some of it will contain 5% antimony. But is shouldn't have increased the diameter.

[popper]

Found it! Sprue plate stop bolt has galled the sprue plate and the crown spacer, closing the sprue plate forced a very small gap at the handle end. Removed the wave washer temporarily, cast another 500 this morning and they drop .313 at the base. Is there a BHN at which one should size vs as cast(for 30-30)? Cast another couple hundred .40 while the pot was hot. Sure is hard to keep it full.