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View Full Version : I broke out a couple of new moulds



Harter66
12-15-2014, 12:38 AM
The first is a 225-55 NOE RCBS look alike.
This being my 3rd NOE but by far the smallest, I did all the wash and heat cycle stuff. Now this 1 took me a bit to get settled in, the issue was familiar to me casting long skinny boolits and keeping things hot enough. I got a lot of boolits with round bases but otherwise perfect and some with perfect bases and pretty consistent drips on the noses and few that were good to go except for the ugly unfilled lube grooves the last few pours were really the best as far as initial glancing QC goes anyway. Even the best aren't upto par but I think maybe some extra tin in the melt will help with most of the fill out. I use a hot plate but it is a new addition so I'm still getting the "feel" for it and keeping the temperatures in sync.

The 2nd is a new to me RCBS 7mm165 SP, another long skinny boolit. Poured from the same pot, the base fill out was poor until late in the pot. More tin I guess, these were mostly frosted but the sprue plate seems to be getting cold, more sprue maybe.

I'm thinking that maybe a heavier plate on the hot plate, heavy sheet metal isn't enough on on the open coils. I have a piece of 3/4 steel I'll be using in the future.

So I guess I've got it all but maybe I missed something.....

Tatume
12-15-2014, 08:52 AM
The bases can be made better if you continue your pour after the cavity is full. Keep a steady stream of molten lean running over the sprue holes for several seconds after the cavity fills. This will keep the contents of the cavity molten, giving the alloy time to migrate into the sharp corner of the base. It will also keep the sprue plate good and hot, again helping the alloy to fill out the base corner.

If you're using a bottom pour pot then keep an ingot mold underneath to catch the overflow. If you're casting with a ladle just hold the mold over your pot.