Needing a little help !!!

[Leatherhead Bullets]

I recently picked up a couple of old Magma Bullet Masters from a local guy that hadnt cast for years. I am fairly new to this hobby, and know jumping to the Bullet Master is a bit of both feet in the pan. I have been spending the last few weeks tuning, fixing, etc. to get the boolits to drop well. They are looking very good, other than some inconsistant pitting/holes in the bases. I am running 6-2-92 alloy, and have been playing with temps etc. as a trial and error in attempts to rid the voids. Some of the holes are multiple pin/microscopic holes, others are lareg cone shaped voids. Looking for some experienced voices here. I have been searching this site and others trying to get pinted in the direction towards solution. Thanks for any help!

[Wayne Smith]

I believe that voids are mostly caused by a too cool alloy/mold combination, allowing the sprue to set before the mold is completely hardened. As the lead cools it contracts. The alloy in the sprue should be remaining fluid as this happens and you will see a draw-down on the top of the sprue, if you can see it with these machines. If you have a sprue without a draw-down you are likely to have a void.

[Leatherhead Bullets]

Wayne,

Thanks for the response. I will have to check it out tommorrow when I get home from work. I appreciate all and any advice.

[runfiverun]

it's from when you cut the sprue.
you are tearing the bases.

if you use the fan and count and keep a consistent rate they will even out.

[Leatherhead Bullets]

I have torn/smeared some, but these fully automated machines are a little different than my master caster hand operated. I do have a secondary fan set up at the rear of the machine before the break / sprue cut. This could rapid cool the sprue. Could the casting temp be an issue? I have ran from 700 ( frosty) down to 620. At 620-650 the bullets have a very mirror / chrome type finish. Just some pitting and/or cavities in the bases.