Pietta 1851 .36 needs reamed

Any way a handyman could ream out a Pietta cylinder a few thousandths with home tools?

I have an extra cylinder that I would like to use the 130 grain Lee conical in. The Lee conicals I moulded out of pure lead will not enter the chambers easily. I thought they would at least slide in easily because of the rebated base. But the rebated base has to be pressed in precluding straight starting. I would like to open up each chamber about .001 or so. I thought of a dowell cut to use some emory with a drill. Even with a loading press they do not start easily at all. I feel that if I could open the chambers up slightly that the rebated base will align the slug better for straight seating.

FYI A 22 grain charge is too much for the bullet to clear the barrel. My 18 grain charger leaves plenty of space. I think a 20grain charge would be optimal. I will chronograph soon and report back.

Bob

See if you can buy a bullet sizer- this is a tool that is used with a reloading press. Lee used to sell hand held presses for a small charge and you could even buy a used/re-conditioned one from them. You place a bullet in position and then operate the lever, the bullet goes through a channel and is squeezed down to the desired size.
Probably less fuss than reaming out every cylinder and you can still use the same balls in the cylinders you are currently shooting.

Lee sizers:
http://leeprecision.com/bullet-casting/lube-and-sizing-kit/

Lee press:
http://leeprecision.com/reloader-press.html

An inexpensive setup. I like the Lee press I linked to as it is great for sizing bullets or depriming cases. Lee's sizer works very well. Lube the bullets first and it goes easier and wipes the bullet clean too.

3/8" hand reamer?

Don't make the gun fit the bullet. Make the bullet fit the gun. Size the bullet so that it's right.

I think ideally the chambers should be the same diameter as groove size. As I understand it, the revolver chambers are often somewhat undersized, and could stand to be reamed out anyway, but if all is well there, don't go opening the chambers up more than that. :wink:

Good advise! Chamber mouths should be at and no more than .001 over groove diameter. Check groove diameter at the muzzle as very often revolver barrels will be constricted under the threads in the receiver and need lapped out.
You can ream the cylinder mouths with a simple mill vise on a drill press table if square and plum. First chuck up a spud or plug gauge in the quill and find dead center of the chamber. Lock down the vise in that position, raise the quill and now install a chucking reamer. Set the depth adjuster and thread lock it with the jamb nuts. Ream it out and repeat the procedure for each chamber.
Chamfer the sharp edge just a bit on each chamber mouth to clean up any burrs. Mike D.

Yesterday I brought my Uberti 1860 Army to a local smith to have him ream/hone the cylinder in addition to recutting the forcing code. If things work out well I'll have him do some other jobs.

I was amazed what a taller front sight and an 11 degree cut on the forcing cone does for the accuracy of these percussion revolvers. :thumbsup:

That's good news if it works. I knew an eleven degree forcing cone angle worked good with lead bullets but was hesitant to try it on a ball shooter. I have both 8 and 11 degree cutters. It will have to jump a bit more before engaging rifling after cleaning up the original steep angle.
One does not want a compound angle in the forcing cone. Mike D.

Many, if not most C&B revolvers have chambers under bore size and accuracy can often be greatly improved by reaming the chambers to just over groove diameter of the barrel.
If the bullet's rebated base is too large to start into the chamber as intended then resizing the bullet won't solve the problem since you would have to reduce the whole bullet to a diameter smaller than the chamber and then it would fall in and fall back out. I've hand reamed my '51 navy with a 3/8" reamer which has a slight lead-in taper at the end. That taper allows the reamer to start in the undersized chamber mouth and by taking care not to run it too deeply the chamber is still a tight fit with .375" balls seated slightly below flush. My reamed Navy with .375 balls and 18 grains of 3f will group five shots into an inch and a half at 25 yards so I do recommend the practice to anyone at all handy with tools.

I think you meant to say, "...most C&B revolvers have chambers under groove size and accuracy can often..."??

I've never seen a C&B revolver with the chamber size smaller than the bore but I most of them have chambers that are smaller than the rifling groove diameter.

I don't know why they do this and it does hurt accuracy.

Several Italian companies have offered special "target" models that have chambers that are equal to, or .001 larger than the groove diameter so it's not like they don't know that this is important.

Had another idea today that is much simpler than the previous one I outlined.
The drill press will still be used but the tool to hold the reamer will be a tap guide made by B-square. The reamer goes in the bottom in a chuck and the top stem goes into the drill press quill.
I use these all the time for tapping holes straight.
You don't even turn the press on but just use it as a guide to keep the reamer perpendicular.
Turn the reamer by one hand and hold the cylinder flat down on the table with the other letting the reamer find it's own center as you turn the T-handle. Mike D.

CoyoteJoe said:

Many, if not most C&B revolvers have chambers under bore size and accuracy can often be greatly improved by reaming the chambers to just over groove diameter of the barrel.
If the bullet's rebated base is too large to start into the chamber as intended then resizing the bullet won't solve the problem since you would have to reduce the whole bullet to a diameter smaller than the chamber and then it would fall in and fall back out. I've hand reamed my '51 navy with a 3/8" reamer which has a slight lead-in taper at the end. That taper allows the reamer to start in the undersized chamber mouth and by taking care not to run it too deeply the chamber is still a tight fit with .375" balls seated slightly below flush. My reamed Navy with .375 balls and 18 grains of 3f will group five shots into an inch and a half at 25 yards so I do recommend the practice to anyone at all handy with tools.

Click to expand...

+1 this is exactly what I was thinking. Letter size drills I have I have used to ream with the press a 1/2 thousandths or so at a time. The "U" size opened things up and a U size is .368 and it was too tight to slide in. But it wound in with the press operating slow. A "V" size is .377 so a standard 3/8ths is in between. A metric 9.5 may be between the U and the 3/8ths but I am not quite there yet. The Lee bullet now fits in up to the second band allowing it to seat straight. I may lap instead of using the 3/8ths drill just to gain a smidgen more clearance.


Bob

Absolutely anything else is just plain :shake: in 2 years time there will be some poor newbe on here wondering why his secondhand gun is chainfireing etc. :td: Came across this very thing this weekend last with a shooter that was having massive troubles with a cb revolver he had just purchased .

This is an interesting thread. I had no idea this was the case with C&B's. My navy appears to actually have a chamber size slightly larger than the bore. Recovered balls have an obvious barrel shape from passing down the length of the bore, more so I believe than just what pressing them into the chamber does (the slight ring of lead shaved off).

Of course accuracy was never great when I was shooting this gun but I attribute that to a few things. First, I didn't have a clue about working up loads and just shot what gave a decent kick but wasn't max loads. Second, the front sight flew off some time back and I couldn't find it. Its pretty durned hard to aim without a front sight! Finally the dumb kid who tossed this kit together (that would be me :redface: ) thought it was a good idea to try and crown the barrel with a Dremel tool........ :shocked2: :slap: What can I say, I was a 20 year old kid who wanted a cool six shooter like dads..

when working on anything screw up the cheap part not the expensive one.
Experience is the thing you get right after you needed it
Bunk

Yeah, what he said... try sizing the back halfs of the bullets to slip into the chambers before reaming the cylinder.
With the chambers half way between the bore and groove diameters the guns can shoot pretty darn good, completely in opposition to conventional wisdom. With a properly aligned long bullet you have more weight of lead but it's more difficult to make accurate, hence the extra steps to make the bullet suit the gun.

Why long bullets don't have a round* backside to enjoy the accuracy potentials of round ball mystifies me. Ah ha! Something else to experiment with!

* or at least elliptical !

There are countless molds out there plus Eras Gone has what, 2 or 3 period bullet molds for the .36 that may be just the ticket for that gun.

Zonie said:

I think you meant to say, "...most C&B revolvers have chambers under groove size and accuracy can often..."??

I've never seen a C&B revolver with the chamber size smaller than the bore but I most of them have chambers that are smaller than the rifling groove diameter.

I don't know why they do this and it does hurt accuracy.

Several Italian companies have offered special "target" models that have chambers that are equal to, or .001 larger than the groove diameter so it's not like they don't know that this is important.

Click to expand...

I actually emailed some manufactures about this. All I got back was "they are just reproductions." Guess their take is they are for looking at and making noise.
An older Walker I have was an accuracy nightmare. It turned out to be one of the undersize cylinder bore. Reamed it to tight .451. Increased cone angle and dressed the crown. Went from 6-7 inches right to dead on the vertical. Fortunately it's the only revolver I have that was this way.

bang said:

I actually emailed some manufactures about this. All I got back was "they are just reproductions." Guess their take is they are for looking at and making noise.
An older Walker I have was an accuracy nightmare. It turned out to be one of the undersize cylinder bore. Reamed it to tight .451. Increased cone angle and dressed the crown. Went from 6-7 inches right to dead on the vertical. Fortunately it's the only revolver I have that was this way.

Click to expand...

I have a 1973 Replica Arms 1861. It happens to be a true .36 in that it is a .375 bore using a .380 ball. It is quite annoying the manufacturers now will not make the bores the correct size. They did what they want not what is correct, even though they are correct verywhere else. Now off my soap box. My gun was made with the barrel not extending far enough back from the web. I can't just file back the web or the wedge won't work. To get the right cylinder gap, the barrel has to be wedged to bring the cylinder gap to being tighter at top of cylinder than at bottom of that chamber. The result is the chamber opening is slightly compressed at the top. So now I will freshen up the chambers with a .376 reamer and lightly chamfer the chamber mouths. My chambers lock up dead center on all 6 si nv the forcing cone is fine. Oh, and degrease and wipe some cold blue in the chambers to cover the fresh cut metal so it go and rust on me.