New molds dropping big

[QuackAttack24]

Just got a couple new molds from arsenal molds, both Keith design, one for .44, one for .357. My plan for these was to cast for 44 mag and 357 mag, so I'm aiming for Linotype hardness. My lead mix is range scrap (usual BHN around 12)mixed with Foundry alloy from rotometals (64.5%-lead, 23% Antimony, 12.5%-tin). I added two small tin pellets to get better fill out. My first batch I tested with the Lee hardness tester the following day, and it came out 20.9, which I was pleased with. I alternated casting molds from the same pot. Everything was air dropped. Odd thing to me was the boolits were dropping bigger than anything I've ever cast with my Lee molds. The 430 mold dropped at a very consistent 436. The 358 mold was dropping 360 boolits.

I know differing alloys can drop bigger or smaller depending on antimony content, etc., but this seemed excessively large. I can use them by sizing them down, but any thoughts for future casting on alloy composition or ideas for reducing the cast size without losing the hardness I want for magnum loads?
Thanks in advance for any ideas.

[cobia]

What helped me to size with the Lee push through die, was to size it the same day and use a little hint of imperial wax. If I had waited a few days they got much harder to size! Cant help with how they fall out..

[zarrinvz24]

Linotype is known for dropping larger, iirc it is one of the largest alloys.

[cobia]

Forgot to mention, I also PC coated and then added a GC and then final step I sized the same day..

[farmbif]

ive found that even full power 357 mag and 44 mag even in a carbine are maybe around 2000 fps and alloy that hard not necessary with gas checked bullets.
ive been shooting just plain clip on wheel weights with maybe 1-2% tin added lubesized, well, for 357 mag at .360 and 44 mag at .431.
if using foundry type to harden up even pure lead it has plenty of tin in it and adding any additional tin may have little to no effect.
but I'm not an expert these are just my experiences.

[Walks]

BOY HOWDY !!!!!!

Why do you need a bullet that HARD !!!!?????

You certainly DO NOT need to add Tin to any alloy with Foundry "Lead" in it. Are you going to run them thru a Lube Sizer ? Will you be PC'ing them ? Check hardness of your bullets next week and then next month. I believe it will only increase. Have you tried to push an unsized bullet thru cylinder mouths ? Are you going to "tumble lube" them and size using a push thru sizer ?

All these questions need to be answered before you go any further.

[ShooterAZ]

Why are you aiming for Linotype hardness? Knowing the purpose of these boolits would be helpful to know. More Antimony = Larger boolits as you surmised, and also much more difficulty sizing them. BHN 21 is something I "might" use for rifle alloy. BHN 15 is more like it as the hardest alloy I would normally recommend for magnum pistols and rifles (think Lyman #2). BHN 8-12 is what I usually use for my handguns. Also if you are using a Lee 6 cavity mold, keep your hands off of the sprue handle! This will cause oversized boolits.

[cobia]

Hey farm, i feel a bit better hearing that, I've been wondering if I need to harden mine up a bit, been using just quinched COWW, GC, coated, sized to .452 on a 300gr for my 454 Ruger casull runnin at 1,600 fps. The seem to shoot just fine after a couple hundred tried, (after many outings)

[Conditor22]

https://i.imgur.com/XJyXxfE.png

Powdercoated I go 8-10 BHN for 38/357 and 10-12 BHN for 44 Mag no GC.

The harder the alloy the bigger the boolit will drop out of the mold

[cobia]

I kinda have to apologize hijacking OP original questions but it also helped with my quest as well here..
I just looked at a measurement with lee tester and measured .052 Lee chart says = 19.3 which = 19.3 bhn, good for 24,703psi. ?
Their chart only go's up to 36.6 bhn @ 46,900psi...
I like the chart you put up Conditor.. Now what to do.. I'll try some bench time and see how they paper and go from there.
I'll digress..

[Dom]

I have an Arsenal 4 cavity 44cal mold. Suppose to drop .430 dia bullets. I'm cast using straight WW, BHN 10.5 to 11. My bullets are dropping out at .434. Did some today . Having a devil of a time trying to size in my .430 sizer. Over 90% rejection rate. Using the exact same alloy in my Lyman 44 mold, perfect . Not one bullet rejected after mold up to temp. My Lee & Saeco molds also doing just fine with my WW. Only problem with over size bullets is with the Arsenal mold.

[QuackAttack24]

Great feedback guys. Thanks. I aimed for Linotype because Lyman's cast handbook recommends that for the 44 mag and 357 mag bullets closest to what I am casting. I ran them all through a Lee sizing die. 44's got sized down to 432 and 357's to 358. I normally powder coat everything. These I might just tumble lube and try a little softer lead mix for the next batch & see how they size out. Has anyone else here ever gotten 436 boolits out of a 430 die before?

[QuackAttack24]

I have an Arsenal 4 cavity 44cal mold. Suppose to drop .430 dia bullets. I'm cast using straight WW, BHN 10.5 to 11. My bullets are dropping out at .434. Did some today . Having a devil of a time trying to size in my .430 sizer. Over 90% rejection rate. Using the exact same alloy in my Lyman 44 mold, perfect . Not one bullet rejected after mold up to temp. My Lee & Saeco molds also doing just fine with my WW. Only problem with over size bullets is with the Arsenal mold.That's interesting. All my other molds cast very close to stated size as well. I've done enough casting to wonder if it was the molds being over sized, or something weird I did with my lead.

[greenjoytj]

From the Redding-SAECO catalog:

Bullet Sizes & Weights – How to Vary Them

The bullet diameters and weights presented in this list are based on the use of Taracorp’s Lawrence Magnum bullet alloy (2% tin, 6% antimony, 1/4% arsenic, 91.75% lead).
Bullet diameters and weights will vary considerably depending on the lead casting alloy used.
This variation can be as much as 1/2% on the diameter, and 8% on the weight among the most commonly used casting alloys. For example, a .358-158 grain bullet might show a diameter variation of .002", and a 13 grain difference in weight.
Of the most commonly used alloys, wheel weights (.5% tin, 4% antimony, 95% lead) will produce bullets having the smallest diameter and heaviest weight, with such bullets running approximately 1/3% smaller in diameter and 3% heavier than bullets cast with Taracorp's metal.
Linotype will produce bullets with the largest diameter and lightest weights.
This alloy will produce bullets approximately 1/10% larger and 3% lighter than Taracorp.
Other alloys of tin and antimony, with antimony content above 5%, will produce bullets with diameters and weights falling between those cast from wheel weights and linotype.
Alloys containing little or no antimony will cast considerably smaller than wheel weights and in some cases will produce bullets too small for adequate sizing.
Within the limitations given above, the weight and diameter of a cast bullet can be adjusted by varying the alloy’s antimony content.
The size and weight of bullets of a given alloy will also vary according to casting temperature. Higher temperatures will result in greater shrinkage as the bullet cools, thereby producing a slightly smaller and lighter bullet than one cast of the same alloy at a lower temperature.

[greenjoytj]

Don’t forget that bullets cast with an alloy containing antimony can continue to expand in diameter for a month after casting.
Wait 4 to 5 weeks after casting to size, particularly if the bullet dropped at a small diameter from the mold.

Also high BHN is not required to prevent leading, its proper bullet fit to the chamber throats and barrel bore and groove diameter.

[Dom]

Using scrap WW metal the Arsenal mold should drop bullets smaller rather than larger. I'm going to contact Arsenal & talk to them about these oversize bullets. If my other brand 44 molds cast bullets of proper size with my WW metal then the Arsenal mold should also. Something is wrong here. I've been casting for over 50 years & never had a problem like this before.

[QuackAttack24]

Using scrap WW metal the Arsenal mold should drop bullets smaller rather than larger. I'm going to contact Arsenal & talk to them about these oversize bullets. If my other brand 44 molds cast bullets of proper size with my WW metal then the Arsenal mold should also. Something is wrong here. I've been casting for over 50 years & never had a problem like this before.
Yeah, I've been thinking about calling also. Seems like more variation than I should be getting just by casting a hard alloy.

[DBN]

Arsenal probably cuts its molds for ww alloy, so your lino alloy will cast .002 to .003 large. I like my 44 boolits to drop .433-.434 sbh and marlin 94.

[243winxb]

Maximum heat will cause more shrinkage as the bullets cool. Frosted bullets hurt nothing, except slightly smaller diameters. Problem is the extra wait time till the mould can be opened.

Lyman has said, sizing down more then .003" will hurt accuracy. Mine drop, as cast, at .360" and size to .3575" Accuracy is very good in the M28, 357 Magnum.

This is not right and needs corrected."The 430 mold dropped at a very consistent 436. "

Mold are regulated using different alloys. LEE 10 to 1 Lead tin. LYMAN#2 . Some use WW.

[earlmck]

Getting that mold completely closed is trickier than it looks and is probably causing your extra diameter in the 44 cal bullet. I have got to where my casting procedure includes a "whack, whack" step tapping on the mold handle joint as I squeeze (firm, not super hard). I do this with all my molds and diameters have got smaller and more consistent. And yeah, I've been casting boolits over 50 years and just discovered this in the past couple years.

[fredj338]

BOY HOWDY !!!!!!

Why do you need a bullet that HARD !!!!?????

You certainly DO NOT need to add Tin to any alloy with Foundry "Lead" in it. Are you going to run them thru a Lube Sizer ? Will you be PC'ing them ? Check hardness of your bullets next week and then next month. I believe it will only increase. Have you tried to push an unsized bullet thru cylinder mouths ? Are you going to "tumble lube" them and size using a push thru sizer ?

All these questions need to be answered before you go any further.

^^THIS^^
You have a lot of tin in your alloy. Try not adding any add'l. 1-2% is all you need for good fill out if that. I get fine bullets with just range scrap.

[Gtek]

How many undersized dropping molds would it take for an even trade for one of yours dropping fat?

[Dom]

Yesterday I tried casting "again" in my Arsenal mold stamped 429421 255gr PB. Using my scrap WW, BHN 10.5 to 11 according to my LBT hardness tester. Same WW alloy I use in 95% of my casting. Of the many molds I own this Arsenal mold is the only one that cast oversize. Bullets came out at .436 to .437 . Ran them thru my .430 sizer & the driving bands were lengthened by at least 1/3. The crimp grove is a narrow slit. Switched molds to my Lyman 250 gr PB 44 using metal out of the same pot as the Arsenal & bullets dropped out at .430 to .431. Using an alloy as soft as I'm using should cause bullets to be smaller, not larger. As to the mold being closed completely I can assure you it was totally closed. I've been casting for over 50 yrs & have never encountered this problem before. I very much like the looks of the bullet the Arsenal mold drops . It is well filled out with clean sharp edges , just oversize. Very frustrating.

[Walks]

I cast some #454190 out of My old 4cav mold once. Used Linotype as I was going to try them out in My S&W M1917. Dad always said to cast hard for the old .45ACP Revolvers and OLD 1911/1911A1 bbl's.
They dropped at .456. I sized them .454, then .452
Shot pretty well, but too much work.

Since found out COWW or even a bit softer, when PC'd works just great.

[QuackAttack24]

Getting that mold completely closed is trickier than it looks and is probably causing your extra diameter in the 44 cal bullet. I have got to where my casting procedure includes a "whack, whack" step tapping on the mold handle joint as I squeeze (firm, not super hard). I do this with all my molds and diameters have got smaller and more consistent. And yeah, I've been casting boolits over 50 years and just discovered this in the past couple years.
Will give it a try. Yesterday I cast some loads with both molds using straight range scrap, which usually comes out to BHN in the 10-11 range. The 44 mold was dropping at 435 and the 358 mold at about 359.5. I'll try the tap tap method and see if there is any change.

[QuackAttack24]

BOY HOWDY !!!!!!

Why do you need a bullet that HARD !!!!?????

You certainly DO NOT need to add Tin to any alloy with Foundry "Lead" in it. Are you going to run them thru a Lube Sizer ? Will you be PC'ing them ? Check hardness of your bullets next week and then next month. I believe it will only increase. Have you tried to push an unsized bullet thru cylinder mouths ? Are you going to "tumble lube" them and size using a push thru sizer ?

All these questions need to be answered before you go any further.

These are being made to shoot out of Henry lever action rifle at 1600 ft/sec. The ones I made yesterday are to shoot out of my S&W revolvers. All will be powder coated. The hard cast bullets I've made for the rifles in the past have shot extremely accurately.