Need a harder alloy?

[Kyle M.]

So here's the deal. I just bought a very clean 90% plus 1884 Trapdoor Springfield. I slugged the bore and got .457"-.458". My 405gr bullets are sized at .459" and cast from the Lee hollow base flat nose mold. I'm using Lyman #2 alloy that I bought from Missouri Bullet Company a few years ago. The bullet lube I'm using to pan lube my bullets is 50/50 beeswax and crisco, that works fine in my .45 colt and .44 special revolvers with both smokeless and BP. In the trapdoor I got minor leading the last 4-5" of barrel after 10 rounds. Minor enough that it came right out with a bronze brush and some solvent. I was using 27grs of IMR4198.

Today I thought I'd load up some BP cartridges for the Trapdoor, I've previously done this for both a rolling block and marlin 1895. But back then I was using commercial cast bullets. My grandfather recently gave me 100+ lbs of pure lead that he has had for years, he and my uncle were really into muzzleloaders about 20 years ago. So I had this bright idea to cast some bullets out of pure lead. Well the issue arose when I went to seat said bullets, even using a powder compression die I'm still deforming the bullet nose when seating the bullet. The mold I was using was a Lee .459" 500gr pointed round nose. I'm also using a standard set of RCBS .45-70 dies.

I have about 100lbs of pure lead and maybe 20lbs of Lyman #2 left. My questions are #1 should I learn how to alloy my pure lead and just make the bullets harder? Is there another seating stem or something available so I don't deform my soft bullets? Or should I just stick with smokeless and try a new lube recipe? I'm not really sure how to approach this issue.

Thanks in advance for any advice.

[dtknowles]

You should use a harder alloy than pure lead. You could get some tin or just use some of your #2 make a harder alloy. You should probably use powder compression die instead of using the bullet. You might could use your bullet seating die with minor mods. You can change the seating stem to match the bullet. You could use less compression. Do you use a drop tube?

Tim

[Kyle M.]

You should use a harder alloy than pure lead. You could get some tin or just use some of your #2. You should probably use powder compression die instead of using the bullet. You might could use your bullet seating die with minor mods. You can change the seating stem to match the bullet. You could use less compression. Do you use a drop tube?

Tim

I have a homemade 24" drop tube, as for the powder compression die I'm only compressing the powder about 1/16" using 55grs of Goex FFG. I probably should get a powder compression die though. In the past my bullets have been hard enough that I could do 1/16" of compression without any issues. I have no issues with using a harder alloy, I just don't know exactly what ratio of pure lead to #2 I should be using. I can always get some more #2 or some tin. I'm not loading these for any kind of stellar accuracy my local range is slightly less than 100 yards and I normally shoot at 50. I'm not much for shooting groups either.

[Ozark mike]

The seating stem needs to match bullet profile
Id try 20:1 alloy with what ya got
Try a little harder lube mix by adding more wax

[Kyle M.]

The seating stem needs to match bullet profile
Id try 20:1 alloy with what ya got
Try a little harder lube mix by adding more wax

Thanks I’ll see what I can do about finding another searing stem mine seems to be more for a flat nose bullet. I’ll also try your suggestion on the lead and lube. I feel like this die set originally came with two searing stems and I somehow lost one but maybe not.

[Ozark mike]

There are many threads here about all those topics by people that know more than i do i imagine they will have all kinds of advice for ya. But just a little searching can net a whole weeks worth of reading material

[Kyle M.]

There are many threads here about all those topics by people that know more than i do i imagine they will have all kinds of advice for ya. But just a little searching can net a whole weeks worth of reading material

Thanks. It seems any time I'm about to start a new project regarding bullet casting or loading a new cartridge there is a ton of info that I can read and there's always conflicting information. Also on a second check I didn't have nearly 20lbs of Lyman #2 left more like 12 at the most. But I have a good 100lbs of pure lead. Looks like I'm gonna have to buy some tin, and it looks like tin ingots are about $20/lb! I may be better off price wise just buying some more #2 lead and mixing that with the pure lead.

[RickinTN]

If you mix your Lyman #2 half and half with pure you'll have an alloy of 2.5% Sb, 2.5% Sn, and 95% lead. This should be a pretty good all around alloy for your 45-70. Your leading may have come from too hard an alloy. I'm playing with a couple of new Marlin 45-70's and the alloy I'm using is about what I've mentioned above cut in half again with pure or about 1.25%Sb, 1.25% Sn, and 97.5% Pb.
Good Luck,
Rick

[Larry Gibson]

Kyle M

First of all, a TD with a groove diameter of .457- .458 is under spec. Should be .460 +. The 3 groove barrel slugs must be measured with a V anvil mic or by using the shim method. Did you use either of those methods? The "minor leading" you mention getting is from the bullets being to small, or not a correct "fit" to the correct groove diameter. Your home made lube should work fine [I use beeswax and virgin olive oil at 5 parts to 4 parts by volume].

Second, You can soften the the #2 alloy by adding an equal amount of the pure lead for a 50/50 mix. That ternary alloy (lead, antimony and tin) will make excellent cast bullets for the TD when using smokeless powder. However, when using BP you do not want any antimony in the alloy which is why most BP cartridge bullets are cast of a binary alloy of just lead and tin. Many use a 20-1 Lead to tin alloy but the the arsenal settled on a 16-1 alloy for the 45-70 cartridge using both the 405 and 500 gr bullets. I prefer the 16-1 alloy for my own BP TD loads.

You can back off the standard RCBS FL die to just NS the cases. However, the standard die sizes the case neck area for .457 bullets and the expander expands the inside of the sized neck for that diameter bullet. That is too much for softer cast bullets. A larger expander made for .460 + sized softer cast bullets is really best to use. With BP the charge should be compressed to the seating depth of the bullet so the bullet just sets on top the compressed BP when seated. The bullet should not be deformed and if it is the compression depth is not right or there is too much neck tension caused by over sizing the neck and under expanding it.

You might find my posts in this thread informative for loadinng for your TD. TDs are a lot of fun to shoot and not really that difficult to load for. They just have their own quirks like many other guns do.

http://castboolits.gunloads.com/show...-and-Equipment

[Conditor22]

I modify my seating stems for the boolit profile I am using.
1) clean stem well
2) lightly lube tip of boolit
3) fill end of clean seating stem with hot melt glue
4) press nose of boolit into glue
5) when cool/cured carve/sand off all excess hot glue.

Seeing the glue is softer than metal it will also give you more tolerances for different profiles


****Some people use 2 part epoxy instead of glue*****

[Kyle M.]

Thanks for all of the info everyone. I’ll try a few of the things mentioned here and let you know how it goes. A couple of things I can point out is 1. Whether it’s right or not I’ve used Lyman #2 in other black powder cartridges without any issues including zero leading. I was totally unaware that using an alloy containing antimony was an issue. 2. I’ve found plenty of people who use .459” bullets just fine in trapdoors. 3. My RCBS expander will expand cases far enough that a .459” 500gr bullet will drop in past the final seating depth if I adjust it all the way down.

I had just assumed early BP cartridges used pure lead like a lot of muzzleloader shooters.

[slk]

I do want to hijack this post but have a question along the original post. What ratio of pure lead and tin should you mix to get something close to Lyman #2 ??

[Kyle M.]

I do want to hijack this post but have a question along the original post. What ratio of pure lead and tin should you mix to get something close to Lyman #2 ??

I believe it's 90% lead, 5% tin, 5% antimony. Missouri bullet companies is 92% lead, 6% tin, 2% antimony.

[Mal Paso]

Rotometals at the top of this page has SuperHard 30% Antimony Lead and Tin if you want to harden some of your pure lead.

[slk]

Well what about if ya don't have antimony. What can you do with pure lead and tin. Any ratios for that? I have hundreds of lbs of pure lead, and lots of pewter...

[dtknowles]

... when using BP you do not want any antimony in the alloy which is why most BP cartridge bullets are cast of a binary alloy of just lead and tin....

I searched a bit but could not find out why no antimony with black powder. Does this apply to BP subs too?

Tim

[slk]

Ok this is what I think I know. Pewter is about 95% tin, and 5% antimony. So if I am just thinking out loud maybe 20 lbs of pure lead to 1 lb of Pewter should make something close to #2 lyman. I was never good at math. If someone else has the answer let me know.

Steve

[centershot]

Lyman # 2 alloy is 90-5-5, 90% lead, 5% antimony and 5% tin. It has a BHN of 15, excessively hard for muzzleloaders or BP cartridge arms.

I'm not saying people can't get good results with it in those application, but, for optimum accuracy you want a softer alloy that will easily obturate.

Pure lead has been the standard for muzzleloaders since forever and remains so today. BP cartridge arms are pretty happy with something like 16:1 or 30:1 lead/tin alloys, no antimony. Why no antimony? Because it makes the alloy harder which inhibits the obturation that is desirable at BP pressures.

Larry Gibson pointed out that the 16:1 alloy was selected by the Army for the 45/70 cartridge. Follow his advice.

[Outpost75]

+1 on Larry's advice. As to not wanting antimony in an alloy for black powder bullets, the reason is that in ternary Pb-Sn-Sb the tin and antimony form an intermetallic compound Sb-Sn which is much harder and less ductile than Pb-Sn used alone. While the additional strength and hardness is beneficial with higher-pressure smokeless loads above 30,000 psi, it is unnecessary and detrimental with black powder because it impairs the ability of the bullet to upset and create a positive gas-seal upon initial shot-start (aka obturation). With hollowbased bullets excessive hardness may cause brittle failure of the base cavity if the bullet upsets at all.

I have never slugged an original Trapdoor .45-70 having a groove diameter under .460". The average of the dozen or so I have fooled with over the years was .462, but I have seen one 1884 rifle which was .468"! With black powder the 1 to 20 tin-lead or 1 to 16 works well at standard velocity. It also works well in suitable smokeless loads which approximate serv ice velocity. Powders of choice for such loads are 4198, RL7 and 3031.

With very mild, subsonic smokeless loads firing 380-410 grain bullets a softer alloy of 1 to 30 or even 1 to 40 works well with faster-burning pistol or shotgun powders. While such loads can be very accurate even to 200 yards, you must exercise extreme caution to avoid double-charging!!! I can tell you from personal experience that a double charge totalling 22 grains of 700-X with #457193 cast 1:20 will not "blow up" a sound Trapdoor, but WILL bulge the chamber, rendering a treasured family heirloom into an inert wall hanger.

[slk]

My intent was loading 45 colt with unique powder. I am currently using wheel weights, but that supply will run out one day. I have hundreds of lbs of pure lead and lots of Pewter.

Steve