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6622729
04-01-2016, 07:29 AM
So, I am sold on the idea of single cavity casting. I have a Lee 6 cavity C312-155-2R mold and I have a great load for my 300AAC AR. I have begun casting from just a single cavity of that 6 cavity mold to aim for a more consistent boolit from cast to cast. It's not that I was having any issues with any cavity, I just want to make each cast as close to the last one as practical. Coming from the same cavity has to be a great way to help that. So, now I'm interested in lapping a cavity to make sure it is round and to try to knock off any oddities in the cavity. I don't know that there even are any, I'd just like to see if I can make a great boolit even a step better. Can anyone describe the process or point to the sticky in which that info is hidden? I poked around but couldn't come up with it.

toallmy
04-01-2016, 07:43 AM
Go to Forum at the top of the page on the left , then go down until you find mold maintenance and design check out the sticky their are a couple ways .

6622729
04-01-2016, 09:11 AM
Found the info. Thanks!

toallmy
04-01-2016, 09:20 AM
Less is more , aluminum goes away quickly .

Bent Ramrod
04-01-2016, 11:15 AM
Step 1 of the lapping process is determining that there is a problem with the mould (or barrel bore) that lapping can fix. It is as easy (or easier) to damage perfectly good machined surfaces with abrasives as it is to improve damaged ones. Good stuff comes off as easy as bad stuff and in neither case can it be put back.

Find a bunged up mould somewhere to practice on, and don't mess with your six cavity Lee.

reddog81
04-01-2016, 11:42 AM
It sounds like you've got 6 cavities to choose from. Find the one that cast the most uniform/round bullet. If you can't tell which cavity casts the best bullet, i'm not sure how you will be able to tell if the bullets from the lapped cavity are any better than they were previously...

Of course you could always try lapping 1 cavity and the worst case scenario is that you end up with a 5 cavity mold instead of 6.