Lyman 311041 Woes!

[Dusty Bannister]

Now that you have the whiskers under control, it is time to work on the alloy and mold temp. You say that the mold is preheated but casts with wrinkles for several casts. That indicates the mold is not up to temp. If the mold is not filling out well, even with the whiskers, then you probably need more heat. While at it, you might as well weigh some small ones and some full sized ones, just to see what you are making. I am suspecting rounded edges or bases but no photos to show what you have. Do you pour a generous sprue or just a little button? How long does it take to freeze over?
Dusty

[centershot]

OS OK,
I had not seen that chart, thank you for posting it here. I was aware that the bullet OD would increase slightly as the percentage of antimony increased. The 94-3-3 alloy I am using was mixed in a 180# batch last year using Lino, pure lead and 50-50 solder. I am very confident of the content.

Dusty,
I have known from the start that this mold only runs well in a very narrow temp range. Too cool, wrinkles. Too hot, the bullets are undersize (.308-.309). For that reason, I prehear, but do not preheat the mould to operating temp. I prefer to approach from below and let the heat build gradually until I get there. The biggest problem I have with this mould is staying in the zone! Once I get that down (IF!) I will be a happy man!

The castings are well defined, even the undersized ones. If I am NOT pressure pouring, occasionally yhe gascheck shank will be rounded. I can see this as soon as I cut the sprue - that bullet goes back in the pot! I pour a generous sprue so that the bullet can draw from it as it cools. That is one way I know when the mould is getting too hot - the sprue thins out and runs off the plate. Freeze over is 3-4 seconds. In 30 years of casting I've never had a mold like this!

[Larry Gibson]

Assuming right handed;

Swirl dipper through alloy and fill coming up from bottom of pot.

Hold mould with sprue plate 90 degrees to the right.

Holding mould and dipper over the pot place spout next to sprue hole and rotate to vertical filling the cavity while slightly raising the dipper letting the alloy stream into the cavity creating a large sprue. Be generous with the sprue as stoppong too soon will make wrinkled or incomplete bullets. Rotate dipper to stop.

Fill each cavity individually the same way in multiple cavity moulds.

Not a nickels difference between the RCBS and the new Lyman style dippers........both are excellent. On older Lyman's w/o the little legs I enlarge the oriface with a drill for a faster pour.

[centershot]

Thank you for that information Larry! I put that to use today, sadly to no benefit. It was another day of experimentation. I bought a small desktop fan, about 4" diameter, and used that to cool the mold between casts. I tried various intervals between casts, with and without the fan. I tried different temps from 650 to 750. It wants to be at 650-670, I get the least rejects there. This was all with the 96-3-1 alloy I mixed yesterday. Using the pencil to fill the vent lines I'm pretty sure I can run the old alloy (94-3-3) at 650 and get the same results. This is what I've been dealing with all this time; the mold tells me it wants 650-670, if I don't overheat it, it runs good. But so many times I've cast3-400 bullets that look good, no whiskers, well filled out, and they are ALL undrsize! It's to the point now that I make 30-40 pours and check them all with my micrometer. Keepers go in the box, culls go in the pot!

[OS OK]

I suppose there's an alternative, that is...if your ready to give up on this misbehaving chunk-O-steel?

Splurge...and buy yourself that mould that you have been wanting to replace this 'pain in the butt'...It irks me to no end to admit that some little inanimate object has 'whooped' me and 'thwarted' my best efforts but...in the end we do have a need for boolits that we can successfully load with!

This dang thing is seriously biting into your shooting time! . . . . . . Use it for a door stop!

[Rattlesnake Charlie]

Dilute your alloy 50/50 with soft lead (close to pure). Too much tin makes it creep, and you don't need that much antimony. I know, it is contrary to specified alloys, but try it. It is easier to add back in. Hey, worth a try. BTW, I always ladle from a Rowell, and try to shoot it right into the hole letting a generous overflow off the sprue plate back into the mold. I probably get more pressure than "pressure casting". Let's keep at this one until solved.

[Larry Gibson]

Would you be interested in sending the mould to me to test? I will pay postage both ways.

[centershot]

Larry, PM sent.

[Larry Gibson]

Got it

[white eagle]

how long you had the mold
if it is new you may have to cycle it a few times
before your mold settles in or try another alloy

[centershot]

white eagle, I've had this mold for 6-7 years or thereabouts, it's "well cycled" by now for sure! Dusty Bannister sent me a PM with instructions to run a diagnostic test, I'm in the middle of that now. Once I assemble all the data the mold is off to Larry to see if he can figure out what is going on.

Just one more reason why I love this forum, you guys are GREAT!

[Tom Myers]

[QUOTE=centershot;4147449]OS OK,
I had not seen that chart, thank you for posting it here. I was aware that the bullet OD would increase slightly as the percentage of antimony increased. The 94-3-3 alloy I am using was mixed in a 180# batch last year using Lino, pure lead and 50-50 solder. I am very confident of the content.
QUOTE]

Here is another chart, generated by the Cast Bullet Design ~ Advanced software, that shows the calculated, as-cast diameters of a vintage Lyman mold 31141 mold, using 14 of the common casting alloys.

Hope this helps.

Click to show full size

[gnostic]

Life's too short to mess with difficult projects. Old molds were made to cast with better metal than currently available. Why not just buy a twenty buck Lee mold and save yourself the heartache...

[centershot]

Life's too short to mess with difficult projects. Old molds were made to cast with better metal than currently available. Why not just buy a twenty buck Lee mold and save yourself the heartache...

I did that. The Lee 170 grain mold casts at .309", to small for my Microgroove Marlin 30-30. I beagled it up to .311" but that made the nose section too large in diameter to chamber.

Better metal? I don't think so. I'm fortunate to have a good supply of linotype, tin and pure lead to mix my alloys from. If all I had to work with was range scrap I might agree with you. Maybe. I have a lot of range scrap, it makes pretty good bullets!

[barrabruce]

I would just lap it out a thou and see how that goes and not even worry about it.
Probably make it more dimensionally accurate anyway.