out of round boolits

[wlc]

I purchased a used RCBS .416-350 mold a while back. Just got time to cast with it the last day or two. It is throwing out of round boolits. Parting line goes roughly .4175-.4185 90* gets me .4145-.4155 (out of about 8-10 I checked). Anyone ever seen this? Anything I can do short of buying another mold?

Second part of the question is what alloy and or temp will make boolits drop larger? I know I've read it here somewhere sometime or another, but for the life of me can't find that info again.

BTW Boolits are being cast with WW lead with a bit if solder added. Boolits seem to be filling out fine, just more or less undersized and out of round.

HELP!!!!!

Thanks!

[Buckshot]

I purchased a used RCBS .416-350 mold a while back. Just got time to cast with it the last day or two. It is throwing out of round boolits. Parting line goes roughly .4175-.4185 90* gets me .4145-.4155 (out of about 8-10 I checked). Anyone ever seen this? Anything I can do short of buying another mold?

It's not unusual to see a offset across the parting line with production type moulds. Not desirable, but it IS common. However the discrepancy you're seeing at 90º to the parting line is NOT common. Best and fastest remedy is to send the mould bloacks with a couple of your cast boolits back to RCBS along with a 'To the point' note as to the problem.

Second part of the question is what alloy and or temp will make boolits drop larger? I know I've read it here somewhere sometime or another, but for the life of me can't find that info again.

Adding linotype will increase boolit OD, as will casting hot (mould expands).

BTW Boolits are being cast with WW lead with a bit if solder added. Boolits seem to be filling out fine, just more or less undersized and out of round.

HELP!!!!!

Thanks!

..............Buckshot

[cbrick]

Also check to see if the blocks are closing completely. Could be lead, a bur OR the alignment pins preventing the blocks from closing. Hold the blocks together and hold the mold up to a good light source and see if you see any light between the blocks.

An increase antimony will help with as cast diameter because antimony shrinks less when cooling.

Rick

[georgerkahn]

Sorry to read of your challenge. I have read of moulds getting warped by being dunked in water to cool them -- but, this may be an urban legend. If I had your mould, I'd clean it as best I could to as close to as manufactured condition; follow cbrick's advise re pins, and then cast using Cerrosafe. (Brownell's sells the stuff -- I bought mine at least 20years back, and with many, many uses and re-uses -- the stuff still works.) Using the Cerrosafe eliminates any questions re your alloy or casting technique; and, quickly will let you determine if and/or how much your boolits are out of round. I'd take the measurements, write them down, and do something else for a while. Then, repeat. I'm sure others on this site are better at measuring than I am, so at least two separate repeat measurments would be the call. A fine vertical Sharpie mark on the Cerr-safe boolit would insure repeatability, too. IF you are in fact out of round, I am at a loss re any advise. Good luck... hopefully this provides a place for you to. at least, start.
Best!
geo

[Jal5]

I sent one back to RCBS out of round with sample BOOLITS. They made it right and returned it in a plastic box too! Send them an email.

[Larry Gibson]

The alloy and cast with alloy to cold will cause the very out of round condition described.

Add 2% tin to the COWWs. A "bit of solder" was obviously not enough.

Was the alloy COWWs or was there some "lead" added also?

Cast with alloy around 725 degrees with both bottom pour and dipper.

Adjust the casting tempo to keep from over heating the mould.

Larry Gibson

[wlc]

Larry the lead was about equal parts isotope lead and COWW. In the OP I said COWW, but forgot that the pot had the isotope in it already. I didn't weigh out the solder, but put in about 16 inches off the roll into a more or less full pot. I'll try upping the tin some more and casting hotter to see if that helps it out before trying to send it back to RCBS. Probably be a few days though as my wife and I both came down with the flu last night. She's in the bed and I'm on the couch. NOT fun.
I'll report back when I try the additional tin.

This is the only iron mold I have the rest are either brass or aluminum. Does iron like to be run hot like brass does? Thanks for all the help folks!!!

[Larry Gibson]

Get well, let us know when your feeling better. Happy New Year, eh?

Larry Gibson

[wlc]

All right, I got to revisit this mold and my alloy today. I started out with a nearly full pot and added enough solder to bring the tin content up to at least 2% (I did not know exactly what the beginning percentage was). I ran it HOT HOT HOT. Boolits still drop out of round and undersize. I emailed RCBS to see if I can get any relief from them. Hopefully they will make it right even though this is a used but new to me mold.

Does RCBS spec their molds for lino or Lyman #2??? I looked on their website and didn't see any recommendation. Would it help in fill out to try one of those? I don't figure it would help the out of round problem though. I really don't want to go to the trouble or expense of finding or having to order in either of those as most of my casting is for pistols and neither are really necessary for that. I was hoping to cast some lighter loads for the 416 Ruger I have so as to enjoy it more. Full house loads are a bit painful both to the shoulder and the pocket book...

ETA: IF RCBS doesn't make it right can the mold be "leemented" or is their someone who can "fix" it? I would imagine a fix would cost about as much as ordering in a new mold though...????

[wlc]

RCBS emailed me back and I'm sending it in.

[Echo]

I didn't weigh out the solder, but put in about 16 inches off the roll into a more or less full pot.

If your solder is 1/8"Kester, as is mine, I found that 21 inches equaled one ounce. Your 16 inches amounts to about 3/4 ounce - in 160 ounces of alloy. About a half a percent. may be enough to sweeten the alloy, but I doubt it.
The suggestions to harden with lino or whatever is a good one - harder alloy casts larger. Not much, but larger.

[wlc]

On my second try with this I actually weighed out the solder and did the math. I know I had at least 2% and it still threw undersize and out of round. I got about the same measurements as my first pot that was only sweetened a little. I emailed RCBS and they want me to send it in with 5 of my cast boolits "for evaluation". What ever that means. Its going in the mail tomorrow or Friday.

Thanks on the tip on the solder though. I know now to actually weigh/measure it out instead of just guessing. However the guessing has worked fine on all my other stuff up till now as far as fill out is concerned. Live and learn. I'm still new to casting and still learning.

[Larry Gibson]

RCBS specs their rifle bullet moulds for linotype.

Larry Gibson