Help with bullet mold

[hatcreek]

I cast a Lee .309 FN , latley when I cast the bullets are dropping at .306, .304, i use COWW for lead, is there some kind of tweak i can do to get these bullets to drop right? I always heat my molds, and water drop the projectile, I never have had a problem with this mold before just latley, I'm sure its operator not the mold itself, any advise would be great. Thanks. HC

[detox]

Is your measuring device calibrated to zero? Calibrate and retry measuring. Casting cooler will help make bullets a little larger. What is melt temp? 700 degrees should be OK ...adjust pace and look for frosting. If you see too much frosting...temps are too hot and causing bullets to be smaller diameter.

Linotype is most forgiving (less temp sensitve) and makes an excellant .308 bullet alloy. It shinks less and fills mould verywell. Softer alloys cast better in larger diameter moulds

[MtGun44]

Very possible that you need a touch of lube on the alignment features to ensure
full closing. It helps to lay the mold on a hard surface BEFORE you close it to align
the mold halves in the vertical plane.

Bill

[Larry Gibson]

i use COWW for lead........I never have had a problem with this mold before just latley.

Add 2% tin to the COWWs and make sure the alloy temp is at 725 +/-. It's winter and as I recall Wisconsin can be cold. If you casting area is colder also you need to run the alloy and mould hotter. Adjust the casting tempo accordingly. Lack of tin in COWWs is a common problem with "undersize" bullets as is casting colder weather.

Larry Gibson

[cbrick]

[I] It's winter and as I recall Wisconsin can be cold. Larry Gibson

The frozen tundra? Naw, say it isn't so! [smilie=1:

Rick

[hatcreek]

Hey thanks fellows, sorry for not responding, anyways I did increase the temp to 725 and added 2% tin, and checked the alignment of the mold, lo and behold nice shiny projectiles, best ever, they measured out at .310, .309 again thanks for your help, more questions to come. GOD BLESS AMERICA! HC