Water Quench Size Variation??

[Rather-B-Huntin]

Got my first mold on Wednesday (Lee 452-228-1R) and commenced casting a couple of hundred yesterday morning. I water quenched all of them, and the sizes came out between .458 - .460. My medium is 100% WW's.
Today, I cast another couple hundred, but let them air cool. They were all in the
.452 - .453 size range??

This is puzzling to me as I would think the rapid cooling would cause the opposite effect? Anyone else had this happen?

[cbrick]

Hhmmm . . . Something else going on here, it wasn't water quenching them. Not .008".

Was there something preventing the mold blocks from closing on the first casting session? Where they round? What did you use to take the measurements, a caliper or a micrometer?

From water dropping? Nope, nada no way.

Rick

[462]

Something isn't right, for sure.

I agree that the blocks weren't closing properly, with the water quenched batch. Whatever the cause, it was corrected by the time you cast the second, air cooled batch. Do another water quench session to see how they compare to the first ones.

[sagacious]

Agree. Something is amiss here. Water-quenching isn't the cause of that size disparity.

Since it was your first mold, and is presumably new, there may have been a burr or metal chip between the blocks. Or you may have been holding the sprue plate lever handle. I have a friend that does that all the time, and isn't usually aware of it. Makes his mold (same LEE bullet as yours) drop large bullets.

The important thing is that your mold drops at .452-.453". That's good news, and right on the money.

[303Guy]

OK, too many knowledgeable folks saying it's not the quenching! Still, just for fun, try air cooling and water quenching alternate casts for a good number and measure again. (Just in case it is the water quenching. :roll: Anyway, that would rule it out conclusively - or confirm it!:mrgreen: ) The whole idea of quenching is to halt a change in physical chrystal growth and/or the migration of atoms withing the cast mass.

[243winxb]

If the bullets are oversize or out of round the mold is not fully closing. A build up of lube, splash of lead, or a burr on the mold block faces are holding them apart. Inspect the mold block faces and carefully remove anything that might hold the mold apart. Make sure to lubricate the locating pins with solid alox/beeswax bullet lube, Lee part number 90007. If these steps are followed the bullets will cast dimensionally correct. http://www.leeprecision.com/cgi/faq/index.cgi
try air cooling and water quenching alternate casts for a good number and measure again. Makes no difference that matters when i tested it. Now in the process to see if they grow in diameter over time. After 8 days, .0003" if any at all. Aloy might make a big difference???

[Rather-B-Huntin]

Agree. Something is amiss here. Water-quenching isn't the cause of that size disparity.

. . . . . holding the sprue plate lever handle. . . . .

I think that may have been my problem. I haven't had a chance to cast anymore yet, but looking back, I do recall holding the sprue plate handle. I'll try again ASAP an report findings.