Enlarging revolver chamber throats

[Trifocals]

I need help and suggestions on this one. I have several revolvers with chamber throats that need to be enlarged. Several have only one of the six that need this, several two or three of the six and several need all six throats enlarged. This involves three different calibers. existing throat dimensions have been determined by pin gauges. I Emailed a person who reams revolver throats using Manson reamers, but did not receive a reply, so I'm looking for a way(s) to do the work myself. Purchasing Manson reamers and the necessary bushings is a price prohibitive situation. I am wondering if chucking reamers would do the job??? They are relatively inexpensive from MSC and can be obtained in .001" increments. I have a small lathe and could make my own bushings. I do not favor using a split dowel or rod and emery paper to enlarge throats as I feel this could easily result in a "coned" or tapered throat. Opinions and suggestions are welcomed. :confused:

[Bad Ass Wallace]

I had a similar problem with my Ruger Vaquaro's in that the chamber throats were .450 and needed to be opened up to .452. Cylmer ground a reamer that did all 6 chambers perfectly.

[Muddy Creek Sam]

http://www.cylindersmith.com/

Sam :D

[nicholst55]

http://www.cylindersmith.com/

Sam :D

+1. You won't have the satisfaction of doing it yourself, but it will:

1. Be done right.
2. Save you a LOT of cash.

[Trifocals]

Cylindersmith is the person I Emailed but never received a reply from. He has done work for me in the past that I was very pleased with. I would use his services again if he would send a reply

[leftiye]

Chucking reamers work fine. Cut .001 undersize, and use the dowel and 600 grit method that you mentioned you didn't like to polish to size. For .001" metal removal, not much will go wrong. P.S. insert dowel/sandpaper from rear of cyl, it will stay straighter, will round the rear of the reamer cut shoulder and polish it. It will only slightly polish the chamber itself if at all IME.

[Char-Gar]

Mount the cylinder in a 4 jaw chuck and using a dial indicator get a charge hole centered. With the back gears engaged on the lowest speed, shove the chucking reamer though with the tailstock center. Of course use a lathe dog or vice grips to keep the reamer from turning.

Center and index another charge hole and repeat until all six are reamer.

Should be a piece of cake.

[ddeaton]

buy the reamer and pilots from Brownells if you have that many to do. That will pay for the tool and then you will have it for the next 6 Rugers that you will buy. What a savings! [smilie=1:

[dwt]

I just had one done by cylsmith,great work and fast turnaround, try a PM over on the Ruger forum

[MtGun44]

Search for an old post under gunsmithing that I reported on this in some detail.

Bill

[Depreacher]

My old Webley MK VI (.45 acp modified)had .449 chamber throats. I ordered the .452 chamber throat reamer and guide from Brownells. Used a hand type tap tool to turn it with, and Do-drill for smoothness. Worked great for me. After the job was finished I sold the set on that large internet site and only lost $15. Seems like I used part of a case neck (.45 colt?) to support the rear of the reamer in the rear of the large chamber. I used maybe 1/2" of the thin neck from a fired case. BE CAREFUL, only slight vertical pressure, never lateral when reaming. Put cylinder on wood 2x4 block with a hole drilled out for the cylinder bushing, and another for the reamerto go through. Simple.

[GP100man]

Elk Ridge Reamer Rentals 1-800-996-0426 give em a call & make a list of questions to ask about the accuracy of there reamers.

You`ll be surprised!!

[MtGun44]

Here is a link to my old post.

http://castboolits.gunloads.com/showthread.php?t=12464

leftieye got it pretty much right on. Leave room to polish to final diameter, reamer leaves
too rough a finish to suit me. MSC also sells laps that will leave a nice finish.

Bill

[John Taylor]

While doing some cylinder conversions I noted that not all chambers were lined up with the bore as well as I would like. I came up with an idea of using a barrel blank to insure that the cylinder bore and barrel were lined up.
http://i95.photobucket.com/albums/l132/johnptaylor/reamingcylinder.jpg
http://i95.photobucket.com/albums/l132/johnptaylor/cylinderreamerandpilot.jpg

[leftiye]

Excellent idea. Better still, a single point boring bar to cut off center holes true to the guide - in a drill guide (smooth bore). Fly in the ointment - is the barrel shank of the barrel to be used cut correctly (concentric to the bore)? A clamp to fix the cylinder relative to the frame in the firing position helps also.

[John Taylor]

Excellent idea. Better still, a single point boring bar to cut off center holes true to the guide - in a drill guide (smooth bore). Fly in the ointment - is the barrel shank of the barrel to be used cut correctly (concentric to the bore)? A clamp to fix the cylinder relative to the frame in the firing position helps also.

In this case the pistol was getting a new barrel. Also the cylinder bolt had a very good lockup when the hammer was at full cock so no clamp was necessary. New barrel and dummy barrel had the threads cut while supported with a live center so the threads should have been concentric to the bore. The owner sent a picture of a 1" group from the 45 LC so I guess I did a good job.

[leftiye]

I was not being critical. The process would be improved with the suggestions. Better is better.

[machinisttx]

In this case the pistol was getting a new barrel. Also the cylinder bolt had a very good lockup when the hammer was at full cock so no clamp was necessary. New barrel and dummy barrel had the threads cut while supported with a live center so the threads should have been concentric to the bore. The owner sent a picture of a 1" group from the 45 LC so I guess I did a good job.

FYI: most tailstocks are set with the center slightly higher than the spindle. This allows for some sag under the load of a heavy workpiece. IIRC, Brownells carries lathe "centering buttons" if you want to check alignment. Not sure of your machining experience, so I thought I'd mention it. 8-)

[John Taylor]

FYI: most tailstocks are set with the center slightly higher than the spindle. This allows for some sag under the load of a heavy workpiece. IIRC, Brownells carries lathe "centering buttons" if you want to check alignment. Not sure of your machining experience, so I thought I'd mention it. 8-)

I have been doing machine work for over 40 years and still learn new things sometimes. I usually use a strait bar between centers with a dial indicator to check alignment. I know one of my lathes has the tail stock a little low. Have not checked the newer one and the other one only gets used for reaming barrels so the tail stock don't matter. Got tired of truing up the tail stock after turning tapers so made this taper attachment so the tail stock does not need to be moved.
http://i95.photobucket.com/albums/l132/johnptaylor/Newoffsetcenter.jpg
http://i95.photobucket.com/albums/l132/johnptaylor/offsetcenterparts.jpg

[machinisttx]

John Taylor:

I have wanted to build one of those and a floating reamer holder for a while but unfortunately the company I currently work for doesn't allow personal projects on your own time. Eventually I'll get back to a small shop and get around to making them....or get my home lathe running and find a decent bridgeport. :D

[leftiye]

Nice center! I need one of those.