There's been some very interesting information on this thread, thanks.

I've only fired modern weapons and that was many years ago so I'm envious of you.

Rob your colt navy firing was this the cap and ball version, I know some were converted to metal cartridge, I know you said you used it two handed, but do you think the kick affected the accuracy of the shot or was the ball out of the barrel before the gun jerked up.
I'm interested in its application to rules for old west guns, i.e. is a gun with a bigger kick intrinsically less accurate?
I would be interested in your opinion.
Cheers