I recently purchased a Howell 45 Colt conversion cylinder for my Pietta replica 1858 Remington black-powder revolver. I have a question that wasn't covered in the instructions that came with it. The cylinder has a seventh locking slot positioned about one third of the way between two of the normally spaced other six. I was wondering about its purpose and proper use. The cap-and-ball cylinder it replaces has no such extra slot.

I think it's supposed to be where you lower the hammer betw the chambers for the gun to be 'Safe'.
The cylinder will lock into that extra slot holding it inbetw the chambers/rounds,, and the hammer will be down inbetw the rounds as well.

Probably better to just load 5,,but JMO.

Thanks! You were right, but it's pretty tricky to get the cylinder lined up right to lock in place properly. It would have been better if they'd have copied the system from the original cap-and-ball cylinder - it has a notch between each chamber position that you can lower the hammer into between the caps - that gives you six safety positions - simple and more efficient. Often seems like the old ways are best, but I guess that would be too much extra machining.

That's what Kenny Howell did on his 5-round .45 ACP conversion for the Pietta 1858.

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