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Discussion Starter · #1 ·
It has been over 25 years since I last cast boolits ................ so I gave it a try again two days ago and I am not satisfied with my results.

What type of consistency are you guys getting regarding size and weight of your boolits? Mine are varying as much as .002 in diameter and 3.8 grains in weight.

I am casting for the first time with an aluminum mold, a Ranch Dog TL432 275RF that I purchased used.

I am also having problems with the base of the boolit having flashing around the edges which makes it almost impossible to get a gas check on. The sprue cutter appears tight against the mold and I can find no junk underneath it. I am getting a good clean cut on the sprue, no smearing.

Thanks if you can help.
 

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Bluesman,

Welcome to the forum!!!!!!!!!

That "flashing" around the base of the bullet has to be because of the fit of sprew plate to the blocks. You might use a bright light when the mold is cool enough to handle and see if you can see light between the plate and the mold blocks.

Consistency, -------- I spend little time measuring dia. of bullets, and little to no time weighing them except -----------

If however, the bullets were greatly different in size or maybe out of round, this would quickly show up when I run the bullets through the sizing die.

For my 45/70 and using a 4 cavity mold for the 465gr bullets, I first sort for visible defects and those that make the cut are then weighed.

I sort by weight into groups of bullets that fall within a 1 grain weight range and after the last casting session the bulk of the bullets fell into two weight groups with 3rd group with enough to save (20 - 30), coming in about a grain or so lighter.

Those that exceeded or were lighter then those three groups were set aside to re-melt. Wasn't many of those

For the handguns, most bullets that pass the visual culling will shoot better then I can, so they just get shot.

I prefer aluminum molds of at least 4 cavities, but have never used any "ranchdog" molds. Lots of people do.

At least some of those molds were made by Lee, and quality wise could be iffy in some cases.

I have some of the Lee 6 cavity molds for handgun banging, just because of the number of bullets I can quickly cast from these cheap molds and then use for non-important/critical shooting.

I hear that Lee has up graded the quality of their single and double cavity molds, but if you have one of the older Lee molds, it is possible it is very well used and needs to be replaced.

Many folk use and are happy with Lee molds, but for anything of importance, I'll pay the extra and buy a custom mold from one of the good mold makers. They ARE worth the extra cost because of the much greater quality and accuracy.

Crusty Deary Ol'Coot
 

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First, welcome back to casting.
Second, anther web sight, castboolits.gunloads.com, is a very good informative place for casting bullets.
third, the flashing is caused by not getting the mold haves together properly. Could be something sticking to the mold halves, the handles not being attached properly, etc.
Squeeze the mold halves together and see if you can see any daylight between them. Observe the closing and find out what is preventing total closure.
Fourth, I threw a lot of bullets back into the melting pot after the first or second casting sessions. They were not consistant and had plenty of little defects. I considered them practice. My latter casting sessions are turning out real good and I have learned a lot of what to do and not to do.
(for example, had to make a sheet metal wind break around my melting pot, a way to pre-heat the mold, a soft towel to dump the new bullets on, now the molds are cleaned with alcohol before their use, found a place comfortable and can sit there for several hours, and now try to limit my casting period to about an hour each time, to prevent fatigue.)
Rich S.
 

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Rich,

I believe the Original poster is talking about a "flashing" around the base of the bullet and not the fins that would form along the mold block lines it the mold blocks are not firmly together. Those defects are caused by a flow of alloy between the sprew plate and the top of the mold blocks.

Although the situation as you describe it and the fins that are caused, would most certainly cause variations in bullet dia. and weight.

CDOC
 

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Your going to have to make sure your hand pressure on the mold handles is the same from pour to pour. Keep the mold blocks clean where they mate . Are the faces flat, and index each other correct?
 

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Discussion Starter · #6 ·
Thanks for all of the suggestions guys. Yes, I am referring to flashing occurring around the circumferential base of the boolit. I have a new Ranch Dog mold I will cast with next time.

Perhaps the used mold I bought has some space under the sprue cutter but I could not see any light through it.

I feel the most likely culprit is my methods. After sorting completely through the boolits I found more consistency among 85% ...... the rest I threw back in the pot to melt the next go round.
 

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Bluesman,

Looks like your getting there.

No magic as far as the holding of the molds is concerned, as long as they properly mate together and as has been said, the faces are clean.

So, the problem with the "flashing" on the bullet base IS!!! simply an issue of the Sprew plate being tight/flat, or not, during the pour.

Sometimes the plate screw needs to be tightened or needs a new, "wave" washer under the screw head and sometimes it needs some help or replacement.

Good luck. Guess I'd try both molds during the next pour.

Except when casting for my 45/70, I regularly run 2 - 3 molds at the same time during a casting session.

Crusty Deary OL'Coot
 

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Re: The flashing around the base of the bullet;

Many make the mistake of having the screw that holds the sprue plate down to a death grip. It's often not unlike pushing down very hard on one corner of a piece of plywood. You will wind up lifting, ever do slightly, the rest of the plate. I own many aluminum molds, custom and Lee, and I get much better results by having the sprue plate just tight enough where it either swings closed or you barely have to nudge it closed. Lee will tell you the same thing. This seems to go against what someone may say is logical, that if I have a void I need to tighten it down. Try it with the plate a little looser and see if it helps
 

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You might also check the underside of the sprue plate for a nick or bump as well as the top of the alum blocks. Ranch Dog actually stones the underside of the sprue plate just to be absolutely certain there is nothing to cause excessive gap.

I've followed his process with a new mold precisely and had much better results. It takes only a few minutes but the preventive maintenance is worth it.
 

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also you might get the flashing if you pressure pour ( if you use a bottom pour pot and put the sprue right on the spout )
you could also have a void in you boolits if your melt temp is low
 

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I guess I throw maybe ten percent back. Or more. I don't think I've ever gotten good bullets out of the first two or three throws, no matter how much I preheat the mold. Practice runs. Most of my molds are two, three, five and six cavity. After awhile they get too hot, and then some of those bullets get thrown back, too. I'll run two or three at a time, trying to get that rhythm of pour, set down, pour the next, pick up the other, knock out the bullets, pour...whew, sounds worse than it is. Anyway, 85% keepers sounds pretty good to me.
 
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