What alloy were 1870's army bullets?

[DLCTEX]

Member Malcolm gave me 6 pounds of bullets he picked up at the Ft. Elliot site at Mobeetie, Most were beat up and distorted, but I saved one that had minor damage. He had some loaded rounds he'd found that are 45-70 inside primed. Most of the bullets are 45 cal and the one I saved weighs 401.3 gr. in it's oxidized state. It has a small hollow in the base that leaves a thick rim. There are three grooves with a round nose. I melted them down tonight and the oxidized outer lead was like a thick shell maybe 1/8 inch thick. I fluxed with bullet lube and saw dust, but most of the outer crust stayed in a granulated ash like state. The 5 pounds of ingots I got are harder than pure lead judging by a fingernail scratch test. I'm sure a lot of tin was lost to oxidation, but Iwas wondering what the original alloy was. Anyone know? Malcolm does have a neat collection of a brass belt buckle, uniform buttons, two piece shoes for mules, and bullets and brass that he found there.

[osteodoc08]

Hmmm, I would have saved some of the good ones as conversation starters. Interesting to say the least. I have no knowledge of what alloy they would have used but I cant imagine it being much more than lead with a little tin put in it at the most.

[powderburnerr]

They used quite a few alloys . .i think the 400gn hollow base was 11-1according to spence wolfs book.

[Larry Gibson]

He had some loaded rounds he'd found that are 45-70 inside primed. Most of the bullets are 45 cal and the one I saved weighs 401.3 gr. in it's oxidized state. It has a small hollow in the base that leaves a thick rim. There are three grooves with a round nose.

Those would have been the M1873 bullets used in either the rifle load (45-70) or the carbine load (45-55). The alloy was 12-1 and was a "compressed" (swaged) bullet of 405 gr weight as per the detailed description in; "Description and Rules for the Management Of The Springfield Rifle, Carbine and Army Revolvers" of 1874. In the later '70s Frankford arsenal began experimentation with other softer alloys as it was found the M1873 bullet of 12-1 alloy did not have the mass to obturate correctly in most TDs and probably never did in the 45-55 load. BTW; the hollow base is revered to as a "dished cavity" and is there simply to maintain correct weight with standardized external dimensions of the bullet. The dished cavity is not a "hollow base as in a minie' bullet and is not there to aid expansion of the bullet skirt as many erroneously believe. The Frankford Arsenal tests resulted in the M1882 bullet of 500 gr of a 16-1 alloy. It also had a dished cavity to maintain dimensions and correct weight. The mass of the M1882 bullet of that alloy does obturate quite well over 70 gr of BP. The later 45-55 bullets were of 20-1 alloy I believe.

Larry Gibson

[osteodoc08]

He had some loaded rounds he'd found that are 45-70 inside primed. Most of the bullets are 45 cal and the one I saved weighs 401.3 gr. in it's oxidized state. It has a small hollow in the base that leaves a thick rim. There are three grooves with a round nose.

Those would have been the M1873 bullets used in either the rifle load (45-70) or the carbine load (45-55). The alloy was 12-1 and was a "compressed" (swaged) bullet of 405 gr weight as per the detailed description in; "Description and Rules for the Management Of The Springfield Rifle, Carbine and Army Revolvers" of 1874. In the later '70s Frankford arsenal began experimentation with other softer alloys as it was found the M1873 bullet of 12-1 alloy did not have the mass to obturate correctly in most TDs and probably never did in the 45-55 load. BTW; the hollow base is revered to as a "dished cavity" and is there simply to maintain correct weight with standardized external dimensions of the bullet. The dished cavity is not a "hollow base as in a minie' bullet and is not there to aid expansion of the bullet skirt as many erroneously believe. The Frankford Arsenal tests resulted in the M1882 bullet of 500 gr of a 16-1 alloy. It also had a dished cavity to maintain dimensions and correct weight. The mass of the M1882 bullet of that alloy does obturate quite well over 70 gr of BP. The later 45-55 bullets were of 20-1 alloy I believe.

Larry Gibson

Dang LG, I love having you around. Thank you.

[DLCTEX]

Thanks Larry, the lead should make good holoowpoints for my 45 acp.

[thompsonm1a1]

I purchased a piece of melted civil war lead from ebay and I am going to melt I down and make some hollow base minnies for deer hunting. I have plenty of soft lead but I want some real civil war lead and make some bullets for my muzzle loader.