Enlarging cylinder chambers

[hmeier4799]

The cylinder chambers on my Uberti 36 Remington measure .371" to .372". the barrel grooves are .380".
Does anybody know where I can get the chambers enlarged closer to .380"?

 

[whitedog333]

http://www.discount-tools.com/creamersindexmain1.htm
Try this web site.

 

[Blizzard of '93]

need the reamer that has a 'pilot' on the end unless the cylinder is set-up indexed in a mill.
Brownell's has hand reamers for gunsmiths. seems someone here has a set I hope he weighs in I'd like to have my .44's reamed true bore size.

 

[DanChamberlain]

What kind of accuracy are you achieving with the current setup?

Dan

 

[R.M.]

I wouldn't worry about the reamer with a pilot. Reamers are for the most part "Self-Centering". If they have a round hole to follow, they'll follow it. I've opened them up just on a drill press.

 

[59sharps]

tri-L or Ball Accuracy will do it. you can get thier Address of the N-SSA web Sight links of interest.

 

[wulf]

When I didn't have a shop I asked a friend to ream
all of my 36 cal cylinders to 380.I bought the
reamer and gave it to him after the job was done.
Sorry I don't remember where I bought it..no guide
and done on a drill press..very simple. All my 36
cal shoot like a 38 special..to me. Patersons 1851
and 1862....also extra back pressure...
Wulf

 

[Blizzard of '93]

I wouldn't worry about the reamer with a pilot. Reamers are for the most part "Self-Centering". If they have a round hole to follow, they'll follow it. I've opened them up just on a drill press.

glad that worked out for you but ask a gunsmith concerning this.
I would use one with the stub pilot.

 

[R.M.]

Any machinist will be able to do a proper job just with a normal reamer and a drill press.

 

[59sharps]

Make sure when they ream they also center ea. chamber on the barrel. not just inlarge the chamber. you will be suprised how many are off center.

 

[Dphar]

The cylinder chambers on my Uberti 36 Remington measure .371" to .372". the barrel grooves are .380".
Does anybody know where I can get the chambers enlarged closer to .380"?

I would carefully test fire with FFFG BP and see how it shoots. Many shoot best with just enough powder to produce about 1/16" of compression with the ball seated just slightly under flush. But this can vary.
You can polish them with a "split stick with 320 wet or dry paper. I would order a .374" plug gage from MSCdirect.com. This will allow you to check the size accurately.
I would stop at .374 and test fire. If the rifling is deep it will likely fill the grooves and shoot OK. If not then you can enlarge further.
Carefully done with a 5/16" steel rod split stick polishing with an electric drill will keep the holes round. Just saw a slot down the rod about 1/2" (for this job) insert a strip of wet or dry and spin with a drill.
Use narrow strips of paper so when polishing the paper is ALL in the chamber to prevent funneling. Final polish with 400 or 600.
Reaming without careful setup in a lathe or mill is asking for problems, pilot or not.

Dan

 

[nkbj]

Amen Dan.
And, I've actually made it work with a dowel rod and some duct tape instead of a split stick. Take a little off, measure, take a little off, measure again and again. Like Gramma used to say, "Measure once, cuss twice".

 

[Dphar]

Amen Dan.
And, I've actually made it work with a dowel rod and some duct tape instead of a split stick. Take a little off, measure, take a little off, measure again and again. Like Gramma used to say, "Measure once, cuss twice".

I double stick tape for some things but the split stick is easier to change paper on and can be wrapped to fit the hole tight.

Dan

 

[Dphar]

Any machinist will be able to do a proper job just with a normal reamer and a drill press.

Yes but each hole is a separate set up without a fixture $$$$

The reamer only "self centers" if everything is lined up properly.
Dan

 

[R.M.]

And a stick with sandpaper on it is better?????

 

[Dphar]

And a stick with sandpaper on it is better?????

I freely admit I never enlarged a percussion revolver cylinder. I almost did a "second gen" Colt 1860 I had but sold it instead.
But I have done some cartridge cylinders. Enlarging a 38-44 to 45 is about the only sure way to get a 45 Colt cylinder that will shoot worth a darn for example.
I have done it both ways.
The last one I did was a S&W 629 that was a few thousandths undersize, .425". I used a .429 jacketed bullet as a "plug gage".
I won't ream a cylinder without a fixture to hold it then its got to be carefully set up even with a piloted reamer, and I have some of these. Finding the center of the hole and all that. If reaming from 38 to 45 there is no choice.
If you only need a a few thousands its often easier to polish it. Saves the buying a reamer or making one from one you buy. No need for anything more high tech than something to spin the rod or "stick".
Yes folks, with brains and care often low tech works as well or better than high tech.
The problem with going to a machine shop is having the "fix" cost more than the entire gun. I would also point out that "machinists" are not "gunsmiths" and this can cause troubles as well.
Dan