Cylinder Chamfering

[user 33697]

I could not find the discussion in the handguns forum concerning making a slight chamfer on the entrance of each revolver cylinder chamber to make it easier to load conical bullets. Can a forum member describe their method that they used to make an accurate chamfer in their cylinder chambers?

 

[Bad Karma]

I could not find the discussion in the handguns forum concerning making a slight chamfer on the entrance of each revolver cylinder chamber to make it easier to load conical bullets. Can a forum member describe their method that they used to make an accurate chamfer in their cylinder chambers?

A really good drill press with the depth set carefully will produce good results. I have not done this in years. seems unnecessary to me.

 

[64Springer]

Take a DIY store 3/4" chamfering tool, hold it your hand and rotate it back and forth to cut a small chamfer.

All you need to do is break the edge a bit.

Just do it evenly.

Sandpaper and bluing optional.

 

[William P Sepessy]

I have done this many times by by hand with a common countersink. The amount of material you remove is very small, you are just trying to remove any sharp edge at the chamber mouth. Given that small amount I don't know how beneficial it would be for centering conical bullets but it sure helps swaging round ball into the chamber instead of shaving a ring of lead from the ball.

 

[andy52]

I've done it numerous times on the other end of the cylinder but would guess it's the same either way.
You'll need a bore guide and chamber chamfered and a little oil That's about it.

 

[45D]

I've done it numerous times on the other end of the cylinder but would guess it's the same either way.
You'll need a bore guide and chamber chamfered and a little oil That's about it.

So the nipples would go in easier?!!

Mike

 

[Dude]

The idea, as I've heard, is to swage the bullet/ball into the chamber rather than shaving a ring of lead. That being the case, I'd think it's more than taking off the edge or rounding it - maybe only a little bit more.

 

[Bad Karma]

So the nipples would go in easier?!!

Mike

He may be talking about unmentionables? ?

 

[Bad Karma]

The idea, as I've heard, is to swage the bullet/ball into the chamber rather than shaving a ring of lead. That being the case, I'd think it's more than taking off the edge or rounding it - maybe only a little bit more.

Well in that case you would only need to remove about a lead rings worth of material from the mouth of the chamber. Probably not much. I haven’t done so in years but maybe it’s worth doing.

 

[M. De Land]

The idea, as I've heard, is to swage the bullet/ball into the chamber rather than shaving a ring of lead. That being the case, I'd think it's more than taking off the edge or rounding it - maybe only a little bit more.

You only want to break the sharp edge on a chamber mouth as to much chamfer allows more lateral gas escapement at the gap.

 

[TDM]

Personally, I’ve never felt the need. Tread carefully.

 

[M. De Land]

You only want to break the sharp edge on a chamber mouth as to much chamfer allows more lateral gas escapement at the gap.

The same thing happens when the edge of the forcing cone gets eroded or is cleaned up with a heavy chamfer from said heavy erosion. I know this to be true from magnum revolver work which exaggerates this problem and really starts gnawing at the top strap.
Setting a barrel back one turn to index at top dead center and shortening the ejector rod housing to get a sharp, clean barrel forcing cone ,on any solid frame gun is a fair amount of work and not for the faint of heart.

 

[nkbj]

The steel used in replicas is typically pretty malleable. You can push a lip onto the bottom of the chamfer when working on chamber mouths. You mite think it wouldn't be a big deal but a tiny bit of constriction on the shaping of the soft lead ball as it is pressed into the chamber can matter. So it's just another little something to be aware of and to check for.

 

[Crow Choker]

The theory behind it is sound but over the last 51 years of cap and ball shooting I've read alot of ya's and nay's of doing so. I've never done it, have never had problems in ramming ball into cylinder except when trying out .457's into Pietta's/Uberti's that .454's work and shave a nice ring of lead.

 

[andy52]

So the nipples would go in easier?!!

Mike

No, that wasn't what I meant. On an unmentionable revolver the chambers are chamfered to facilitate the use of a speed loader.
so, on a CB revolver it makes since to do the same on the feed end to help when seating a ball.

 

[45D]

No, that wasn't what I meant. On an unmentionable revolver the chambers are chamfered to facilitate the use of a speed loader.
so, on a CB revolver it makes since to do the same on the feed end to help when seating a ball.

I know, I was just funnin' ya.

Mike

 

[ernbar]

I wonder if the carriage bolt and valve grinding paste method done lightly will work at knocking off the sharp chamber mouth edges?

 

[andy52]

I wonder if the carriage bolt and valve grinding paste method done lightly will work at knocking off the sharp chamber mouth edges?

Normally a chamfer tool has a little steeper angle than a carriage bolt would but it would be worth a try.

 

[Dude]

Along this same line, what should be the angle of the forcing cone? I have one that's a bit rough and needs smoothing. I'd like to turn down a tool with the proper angle and polish with valve grinding compound.

 

[1861colt]

There is another reason for chamfering the chamber mouths that Colt did as indicated in his publication - "On the Application of Machinery to the Manufacture of Rotating Chambered-Breech Fire-Arms, and Their Peculiarities, Vol. 11" for the purpose of preventing chainfires.