Does the cartridge move to the rear when fired in a revolver? Then move forward again so the cylinder is free to rotate? Why does a primer in a case with no powder, leave a high primer? I'm guessing that's because the cartridge (or cylinder?) moves to the rear under recoil when using a charge.
Does a fired cartridge in a revolver cylinder move during firing?
- Thread starter Grizzlypeg
- Start date
A long time ago I made up some wax bullets for my 38/357 revolver and right after the first shot, the primer was raised and the cylinder wouldn't rotate properly. This suggests to me that in some or all revolvers the cartridge is held to the rear, maintaining the primer flush with the case. Then the other day when shooting my Blackhawk, I noticed some cases were stiff to eject. Yet the cylinder didn't have any impediment to turning smoothly. So did those cartridges move or not? If they were stiff, when did that occur?
When a primer detonates, it drives the primer back out of the case as far as it can go. When the powder ignites, the pressure then drives the case back as far as it will go, re-seating the primer flush.
In a bottleneck rimless rifle case, the same thing happens, except the case is is also pushed forward as the primer is pushed back. This can shorten the case shoulder a bit. When the powder burns, the pressure then pushes the case back and probably stretches the case a bit, as it sticks the chamber wall.
If the powder charge is mild, the case may not get pushed back against the bolt face, leaving the primer sticking out. Newbies think this is a sign of high pressure. It is the opposite.
In a bottleneck rimless rifle case, the same thing happens, except the case is is also pushed forward as the primer is pushed back. This can shorten the case shoulder a bit. When the powder burns, the pressure then pushes the case back and probably stretches the case a bit, as it sticks the chamber wall.
If the powder charge is mild, the case may not get pushed back against the bolt face, leaving the primer sticking out. Newbies think this is a sign of high pressure. It is the opposite.
I used to play around with primer powered stuff many years ago. Speer used to make plastic cartridge components and the primer was seated into the plastic base by hand pressing it onto a primer resting on the table. Due to the generous tolerances in the primer pocket, the spent primer would back out on firing allowing only single action shooting, depending on the revolver. I also tried wax bullets in real cases but enlarged the flash hole with a drill bit (clearly marking them and keeping them aside from other stuff) which alleviated the primer bulging issue.
