newish Lee 356 125 2R has become troublesome

Dusty Bannister

Well-Known Member
If the alignment pins shift a little, the blocks can tilt as they are being opened and this can result in less than a clean release of the casting. If there is any slight sticking of the mold halves, you may want to check the pins and see if they have moved. Since you noted the bullets were sticking in the right mold half, (this is the one with the sprue plate attached) depending upon where the handle is when the mold is opened, the block would be twisting as you release pressure. If there is a slight bevel base cut in the mold, that combination could be part of the issue.
 

JonB

Halcyon member
you can also see the little bevel on the base I was talking about.
the sprue plate pushes right there.
Yesterday morning, I got out my loupe and had a close looksie.
While I don't think there is a bevel (I can't see it anyway) Sure enough, there is crud (lead or oxide?) built up where the bevel is or where the bevel would be...on the right side mold half only.

>>>Thanks Fiver ! It appears this is the main issue.
BTW, I didn't have a clue what you meant the first time you mentioned it...my bad.

I tried cleaning it with solvent and firm plastic brush...crud still there, so I got out the dental picks and carefully with a light hand, using a rounded dull pick, tried to scrape the crud out. I got some out, but at the time, I thought I got it all out. I cleaned it up with water/dishsoap, gave the cavities a bit of butane lighter smoke and preheated the mold while heating up the pot.

I cast some. The bullets were still clinging to all the cavities on the right side...but the bullets weren't clinging as tightly as they were before, So I made headway. I'm gonna try to get at this later today...I'll at it closer again...but I suspect I'll be spinning bullets (coated with polishing compound) in the cavities...but I may try a couple other things first...which makes me think, I should apply some kroil type solvent right now (a few hours before I have time to get at it).

OH, just had a thought after all I typed in above...
maybe I should heat the mold to casting temp and use "bamboo skewer and beeswax" technique, like when I remove tinning from a brass mold.
 

JonB

Halcyon member
Well, I got it dropping good, but three cavities are a bit larger than the others.
All were .357 x .358 (129.0gr)
Now, three are .359 (129.5gr)
and the other three are .360 (130.3gr)
I've never increased the size before by spinning a bullet.
they'll size to .357 just fine and will be fine for shooting in auto-pistol, but learned a lesson that the spinning can be overdone.

It's a long story why I over-did the spinning, the short version is, Using the dental picks to scrape out the lead deposits made some scratches (I thought I was careful, but with a loupe, the scratches are easy to see), and I tried to remove the scratches with 'extra' spinning. The stickiest cavities were in the middle, so those three got more scratches and subsequently got more spinning. BTW, the scratches are still visible and luckily they don't transfer to the bullet.

Note to self, I 'should' have cleaned the mold with solvent after the spinning, as the polishing compound I used must have some wax? I'd assume the solvent would remove most of the wax, where as, the dish soap/hot water/tooth brush must not have? I was casting wrinkles, even on frosty bullets, for a couple hundred pours, before the wrinkles disappeared. Just glad that the mold drops 'em easy again.
 
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GRMPS

Active Member
Glad the mold is working now, sorry about the scratches and size difference
How coarse a polishing compound did you use with the spinning?
I like to use the hardest alloy I have to make the plugs for spinning.
I'm surprised heat and bamboo didn't clean it
I'd have been tempted to stick the whole mold in a pot full of lead and leave it until the lead no longer stuck.
 

fiver

Well-Known Member
you can open soft aluminum with toothpaste and comet real quick [20 seconds or so will get you over a half a thou]
 
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JonB

Halcyon member
while I said polishing compound, I actually used automotive turtle wax rubbing compound. It's red, so I suspect it has the rouge type of polishing medium in it?
I've done several Lee and NOE molds in the past, I would count the seconds, and was always under half a minute per cavity, but the last mold I did was a Lyman, and I spin the heck out of that one (of course that's Iron)...so that was probably in my mind when I did this Lee mold (my BAD). I suspect I was spinning the 3 middle cavities for a couple minutes each, then cleaned, then refreshed the compound on the bullet and spin another minute or so...the other cavities likely only got half the spinning.

 

JonB

Halcyon member
The bamboo skewer and Beeswax and Hotplate, probably did remove most or all the lead deposits.
BUT, after that, I did some feeling around with the dental picks...I swear I could feel something on the 3 middle cavities, that's when I thought I better spin some bullets...it's too bad I didn't clean it up first, and do some test casting
:embarrassed:
So, before I did the spinning, I did more scratching with the dental picks, a little more aggressively then previously, and made bigger/deeper scratches. But couldn't seemingly get anything more removed. Then I did the spinning, and trying to cleanup the scratches. After I cleaned everything all up, but before I started casting, I did the "feeling" around with the dental picks...it seemed like there was still something there. Got the loupe out, couldn't see anything but scratches. Then I butane smoked it and started casting ...and casting went well. After typing this all out, and thinking about it, I am betting the one dental pick must have a extra sharp edge or burr on it? to give the impression of buildup on the round mold cavity? MAYBE ?
 

Ian

Notorious member
Shoot all the cavities with a couple coats of FA mold release and wipe the block faces clean. Should solve stickage and oversized problems at the same time.
 

fiver

Well-Known Member
I'd open the others with a bullet from the middle cavities first.
if I'm gonna 'fix' something I would at least try to get them close to the same size, then I could deal with them through the 'process'.
 

JonB

Halcyon member
I'll probably run with it, like it is, for now. BUT, if it becomes troublesome again...I'll surely be trying just that, attempt to uniform them and mold release spray
 

Dusty Bannister

Well-Known Member
I'd open the others with a bullet from the middle cavities first.
if I'm gonna 'fix' something I would at least try to get them close to the same size, then I could deal with them through the 'process'.
By middle cavities, I take it to mean the smaller cavities and leave the large ones alone? Let the size of the grit of the compound do the work to lap them larger. I am not in favor of mold release spray. That will make the cavity smaller and is a patch not a solution.
 

GRMPS

Active Member
"If it's not broken why fix it" -- ie I would try a group with each size bullet with identical loads off a rest and see if it actually makes a difference before I did anything else.

Handguns aren't as picky as long guns (unless your planning on shooting 50 yards with a 9MM :) )
 

Ian

Notorious member
I am not in favor of mold release spray. That will make the cavity smaller and is a patch not a solution.

Agreed fully, but he has already made some of the cavities possibly too large and is discussing making the rest of them match, hence the recommendation for the patch.
 

Ian

Notorious member
A new revolver in 38/357 with slightly larger cylinder throats would be an excellant solution to the problem.

Agreed. Nice old Model 10 should print right on top of the front blade at 15-25 yards with that one and the RN falls right into the chamber.