[calex59]

A company called Barnes has been making copper bullets for a long time and they are quite successful. The bullets act very much the same as lead does, they expand well and do a good job on game. I am not defending this idiotic move by the military but merely stating some facts. I like lead bullets and have a hard time imagining anything else would work well in my muzzle loader:).

However, Barnes bullets have quite a following, or they used to have at any rate.

[calex59]

I should add that Barnes bullets also cost about 36 dollars, and up, per 50 bullet box.

[Ruy Dias de Bivar]

Years ago, a gunsmith (I can’t remember his name, he was from Trinidad, Co, later Salt Lake City) who designed a .22 cal bullet made mostly of copper with a small lead tip.

He said it was devastating on even big game in that it opened up, held together and went through the animal like a small buzz saw.

[USFRIENDINVICTORIA]

Interesting facts, thanks.

Just based on the relative specific gravities of lead and copper; I would expect copper bullets to have a significantly higher muzzle velocity (given the same load, etc.) than lead. However, that higher muzzle velocity translates into more air resistance — combined with a lower density, they should lose velocity faster than lead bullets.
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After writing the above, it finally occurred to me to “look it up”. Here’s what one manufacturer has to say about their copper bullets.

http://site.cuttingedgebullets.com/pages/lead_vs_copper