Hi all cylinder pistol shooters

[Scimmy]

I got into a bit of a pickle with trying to find the correct size ball/conical for my .44 Armi San Palo (Euroarms now) new model army.
Just noticed that the chambers are in fact countersunk for the 1st 1.5mm or so a larger diameter than the rest of the chamber. Was trying to achieve the shaved ring if lead on loading for a good seal and was going up and up in size to the point it was hard to seat the ball down onto the powder.

The gun was built 1979 and unfired and still in its box smothered in preservative when I got it.

Has anyone else noticed their cylinders have the above chamber features. Using a mates new model army I think its Uberti, it would appear that his cylinders are parallel and shave a ring off from the start although saying that my pistol centers the ball a treat before ramming.

Cheers all

[lilguy43uk]

My NMA replica uses .454 round balls and the chambers aren't countersunk. If you're worried about flashover, use a semi-greased felt wad over the powder.

[steve medlock]

Scimmy,

You might want to measure the chambers, (digital calipers are dirt cheap now and so useful!) and say just try the next largest ball size.

I rhink the main disadvantage of going too small is that the recoil can move the balls forward whereas you want them to stay put until fired for a number of reasons.

One the ball exits the chamber the forcing cone swages it down to the calibre of the barrel.

Steve.

[Scimmy]

Cheers Steve I'll look out for a set of calipers.
The forcing cone you mention (good description) is in the actual chamber when seating the ball/conical down into the loaded position.
After looking more closely at the pistol there is as you say another cone area at the breech end of the barrel to send/ catch the ball centrally to the bore.
Cheers

[Smokeless Coal]

The forcing cone is at the start of the barrel. The cylinder will be misaligned to the barrel to a very small extent within manufacturers tolerances. The cone forces the ball to a better position.

In a cartridge firing gun the bullet sits right at the start of the rifling. It does not go straight forwards but takes up the helical motion from that start.

With m/l revolvers there is no rifling in the cylinder nor in the forcing cone. The ball starts moving forwards without twisting for over half an inch, then we are asking it to change state to a helical movement.

Accuracy can be improved by keeping that distance as short as possible. Rather than seating the ball a long way into the chamber it should be as close as possible to the barrel.

[Jim McArthur]

I never thought of all that, Smokeless.

Cheers,

Jim

[somtec]

Hi
Another problem that can have an effect on accuracy is that some cylinder chambers are in fact undersize compared to the bore diameter so that when you load the balls you can shave to much off and it doesnt grip the rifling properly.
Ive never checked this myself just read about it on another forum where the guy made a chamber reamer so that the chamber was opened up to a couple of thou larger than the bore or as close to the correct bore size as possible.
Peter

[Eagleman]

Accuracy can be improved by keeping that distance as short as possible. Rather than seating the ball a long way into the chamber it should be as close as possible to the barrel.

Which is presumably the entire point of using "fillers" like semolina in between powder and ball.

[steve medlock]

Not strictly the entire point - it also fills up any void between powder and ball if the rammer is unable to seat the ball that far into the chamber.

Steve