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Drm50
02-13-2019, 01:29 PM
I have been casting since I was a kid. The older guys that I learned from were mostly casting pistol bullets for target. Tin was easy to get in this area and was always added. They had no hi tech testers. They went by uniform ratios of WWs/ Lead and tin. When casting a few bullets for the odd rifle they just upped WWs or used pure WWs with tin. I still cast the same way. I'm casting
boolits for target pistols and older low-vel rifles. For the old rifles I cast as soft as practical. The
only hard bullets I cast are 45/70 & 375W for modern rifles. My question is at what percentage point are you wasting tin? I have bullets 25yrs old in plastic jars that still look like chrome. I've
had guys tell me I'm wasting tin at 20lb bullet metal : 1 lb Tin.

JBinMN
02-13-2019, 01:46 PM
If my math is correct, you are at 5% tin in that alloy. or, 95% "boolit metal" & 5% tin.

20/1 lead/tin results in about 10BHN. If you use WW that BHN will increase as the WW alloy content increases.

If you look at some of the alloy ratios you can get an idea if you are "wasting tin", or not.

It is "your" melt & your results in the boolits. If you are happy with it, no need to change.

So, "you" are the one who decides if you are "wasting tin", & no one else.

If you want to reduce the alloys you are making then I will offer you a couple things.

You can read the article here: http://www.lasc.us/castbulletalloy.htm

Look at the chart below for comparisons of what you are using & what can be used in regard to hardness:
http://i813.photobucket.com/albums/zz53/Dollar_Bill_2009/Relative%20Hardness_zpsif8gbppz.jpg~original

Of course there is more info out to be had. but it will all depend on just how "deep" you want to go to find out more.

If you are happy with your results, then , "No", IMO, you are not "wasting tin".
;)

BTW... If you are recovering your own boolits with a bullet/boolit trap, then you are not wasting much at all, since you are re-using your metals.
;)

Dusty Bannister
02-13-2019, 01:51 PM
Without knowing how much tin is in the bullet metal to begin with, that question has no valid answer. So moving along to try and give a comparison, most feel that Lyman #2 is pretty expensive and most will use something like 2-6-92 as a comparable alloy if they have to buy it. Others like 1-3-96 for pistol alloy. That is sort of like COWW with 1% tin added, as a rough guestimate.

So this suggests you may save money by using less tin, but without any idea what you have, there is no valid answer. More important is if you are happy with your bullets. If so, and they work for you, you already have your best answer. Dusty

Hickory
02-13-2019, 01:51 PM
1 lb tin to 50 lb lead = 2% tin
1 lb tin to 100 lb lead = 1% tin

1% is usually enough for good Boolits.

MaryB
02-13-2019, 06:07 PM
I use Lyman #2 I blend myself. But I have a huge supply of WW and printers lead(linotype and foundry type). More than I will use in my lifetime... got a deal from a print shop, 25 cents a pound, I load it all myself. Came away with 200+ pounds of printers lead, 40 of it in factory pigs. Since I am shooting a lot less these days it is going to last a long time!

Drm50
02-13-2019, 07:00 PM
I base my alloy on WWs / known Lead. The WWs are my problem. Lead & junk lead of unknown alloy is no problem I have literally tons of it. I melt outside and pour ingots and stamp PB for lead and JK for junk. If it's
Mono or Lino I stamp as well. I don't get the WWs I use to because of new stick ons. I've got several hundred lbs of tin but the supply is shut off and will only be picking up the odd ingot that went home in a lunch bucket for sinkers. I'm going to back off to 2% and see how that works.

RogerDat
02-13-2019, 08:48 PM
I sort of agree that if it makes good shooting bullets it isn't "wasted" however one is probably being smart to explore other options that might extend that expensive tin further. Might expect with less tin there could be a need for a bit higher temp or change in casting rhythm. Tin lowers melt point.

The "rule of thumb" I have heard for WW + tin is above 2% is wasted. Tin adds little to the hardness and WW is already probably hard enough for many if not most uses. So 1% helps the fill out by reducing surface tension and helping lead flow. That improvement won't really get noticeably better above 2% hence the idea that above that it is "wasted".

If the source of lead part of the mix isn't COWW's then it can change things. Tin/Lead alloys the tin is the source of hardness. The transition to higher velocity black powder cartridges in rifled barrels required some tin to make the lead hard enough to not lead up after a few shots. Maybe a someone that participates in black powder cartridge sport can weigh in, they are I believe only allowed tin/lead alloy for their bullets in order to be period correct.

Then there is the alloy effect, the sum being greater than the sum of the parts. Antimony and tin will alloy with each other so while Lyman #2 is 5/5/90 and Hardball is 2/6/92 and both have pretty close to same hardness they will have some difference in their characteristics. The #2 alloy is balanced so the antimony and tin will have a high amount of them become an alloy. The popular 3/3/94 alloy that many make is gaining from having the same balance between those two elements.

Hardball is using 6% antimony because that ingredient is cheaper than tin. I have read this is a result of commercial bullet casting manufacturers needing a certain hardness and desiring a cheaper alloy so antimony is increased and tin is decrease but still at levels that will facilitate good flow and sharp edges.

Sort of off on a rabbit trail but the more tin in the melt the more copper an alloy can hold. Copper used to make a bullet tougher rather than harder. Copper can help prevent fragmentation on impact with bone in a hunting bullet or help a hollow point stay in one or at least fewer pieces. Since hollow points are generally cast soft I could see a high tin/lead alloy if one was adding copper to the mix and needed the tin to hold it in the alloy.

One thing about having too much tin for the specific use intended, cutting original ingot 50% will cut that tin in half. Easy to take 3/3/94 and cut it by half for 1.5/1.5/96 or Lyman#2 to 2.5/2.5/95 If you have 5% tin a simple 50% cut would give you 2.5% and alloy you to stretch your tin twice as far. If in some applications the 5% is required you can just not cut the ingot with more lead and use as is. Or cut with say COWW's to get an increase in hardness from the antimony.

I know one can buy or if one is lucky find scrap 5% tin solder. I always hold that out because it is usable on it's own, or an easy mix with lead or WW's to get a different alloy. Hollow base wad cutters are soft, which is one place that 5% alloy sees use.

RogerDat
02-13-2019, 09:03 PM
I would add if your JK batches are large you can send sample from each to member BNE for testing. That would allow you to know exactly what alloy you have in the unknown junk ingots. The alloy calculator has a spot for enter your own alloy so you would be able to plug in the testing number and build from that.

William Yanda
02-13-2019, 09:17 PM
Have you read the Cast Bullet Notes from LASC? The three part alloy, tin, antimony, lead is explained there very well. Talking about the lead/tin without considering the effect of the antimony in the coww's is ignoring a major part of the situation.


I need to explore the effect of more tin than antimony in an alloy. Seems I recently saw a statement to the effect that it was detrimental, but I can't remember where I saw it. Sadly, that happens more frequently recently.
Bill

JBinMN
02-13-2019, 09:33 PM
Have you read the Cast Bullet Notes from LASC? The three part alloy, tin, antimony, lead is explained there very well. Talking about the lead/tin without considering the effect of the antimony in the coww's is ignoring a major part of the situation.


See post #2, First link. {This one >> http://www.lasc.us/castbulletalloy.htm }
;)

Of course there are other things to look at there, but I thought the link in post#2 & the same/above link here in this post was the most pertinent to the topic.
;)

Here is the link for the LASC Cast Bullet Notes, if anyone has not seen the other articles there:
http://www.lasc.us/castbulletnotes.htm

bangerjim
02-15-2019, 08:22 PM
1-2% is all that is needed. I have never used more. Many times LESS! And I have well over 400# of pure Sn in my stores, so it is not from a "frugal" standpoint for me.

banger

468
02-16-2019, 09:16 PM
Drm50, if this hasn’t already been suggested, you can probably swap someone here for some WWand/ or lead. I’ve done that before. I swapped it 1 to 10 for some pure lead. I think I gave a few people a really good deal.

But as JBinMN suggested, if you’re happy, that’s all that matters.

fredj338
02-25-2019, 02:10 PM
I get by for most pistol bullets using just range scrap. I add tin when making LHP to help casting & make the LHP more ductile for expansion. In general, I think most agree you are max out at 2% tin.

Burnt Fingers
02-25-2019, 07:03 PM
Tin rich alloys were used over 100 years ago because that's what they had. Antimony was uncommon.

lightman
02-25-2019, 11:18 PM
Tin basically reduces the surface tension making it flow better and fill out better. Anywhere from .5% to 2% usually works well. 5% is considered wasteful now days. Lyman #2 alloy at 90-5-5 is a pleasure to cast with but tin was much cheaper and more readily available in the past.

Petander
02-26-2019, 09:13 AM
I have bullets 25yrs old in plastic jars that still look like chrome.

Me too. Do you get your lead back? I can re- circulate most of mine, my alloy is the same old tin-rich because back in the day I made big ingots and mixed monotype in. I have 10%,30% and 50/50 ingots. All make good bullets.

I do "dilute" it with pure lead sometimes,not to "save" tin but rather WW.