Apropos of the earlier post re: the implausibility of a Winchester 73 being used in a movie (Slow West) set in 1870, I thought you might like to know that there are several other similar inconsistencies in that film, something I’m sure their armourer would have informed them of at the time.
The Sharpes Rifle which uses those large metallic cartridges is known as a ”Sharpes 1874” for obvious reasons. As your correspondent pointed out it is was mainly used for shooting buffalo and because the gun is so long (1.2 metres), to fire it from a kneeling position means one would probably have little chance of hitting that silly little house made from machine sawn timber, let alone a human being. The recoil would be such that it would probably result in the shooter being slammed on his back only to mutter “Bugger, I must learn to shoot lying down and rest the barrel on something stable.”
The shorter of the Colt 45’s is probably a Peacemaker (how’s that for irony) which didn’t start being manufactured until 1873, while the longer barrelled one is most likely any Army Colt which wasn’t produced until 1875 — even then both of these early models would have needed to be cocked before each round was fired. The most common hand guns immediately after the Civil War were military issue Remingtons and Navy Colts both of which used percussion caps.
The Derringer would have been around at that time (though those folk would never have been able to afford one … nor the Colt for that matter) but was so inaccurate that to shoot someone from that range would have had more to do with luck than where it was being pointed.
On a completely different note, last Thursday night I saw the world premier of an Australian movie The Daughter (Simon Stone, Australia, 2015) at the Sydney Film Festival. Based loosely on the Ibsen play The Wild Duck, it managed to cast an Indian Runner as the duck and I’m sure the poor creature must have been utterly dismayed when it was dramatically released into the wild here in Australia; which begs the question: did Ibsen ever write a play called The Domesticated Duck?