Throating

[750k2]

I'm taking the dive into throating my revolvers.
Is it that big of deal to throat a cylinder on the gun without
removing the cylinder from the crane/gun?
Any other tips to avoid hassles?:drinks:
Thanks

[uscra112]

Throating meaning you're gonna run a reamer into the chambers? I'd sure want to have the cylinder off the gun, so I could hold it firmly and conveniently so I could be sure the reamer runs true.

[missionary5155]

Greetings
Be sure to have the reamer supported so it cannot wobble if turning it with a hand held tool.
A drill press is very nice just turning the chuck by hand. But I still add a bushing on the reamer shaft so it stays centered at both ends.
Mike in Peru

[Mal Paso]

I just reamed the throats on 2 44 Mag Revolvers using a Manson Reamer. The stated size was .431 but the reamer I received was larger. I talked to Dave Manson and their tolerance is .431 to .4315. If you want it to the tenthousandth, call Manson directly. Brownells sent me a replacement, very fast, that was still over. I broke it in on an old carbon steel die before throating the Anaconda and the finished throats are .4312. Buy all the pilots! The reamer works better and you get a set of precision plug gauges. I pulled the Cylinders on both revolvers removing the crane on the 629 as it was easy. I used a Tap Wrench to turn the reamer. You use the tightest fitting pilot for each chamber, (they were not all the same) the reamer almost lines itself up, and the cutting happens only a couple hundredths back of the pilot. Those flutes are to clear chips and keep center, they don't cut. I held the cylinder in my left hand and turned the reamer with my right. I oiled the throat and reamer too. Turn clockwise only so you don't back over a chip. Once I was through I blew the chips out with compressed air before removing the reamer. The instructions were good.

.4312 is perfect! Better than .431 I thought I was getting and better than the first reamer I got. Manson direct is the way to get it to tenthousandths otherwise .431-.4315 is the 44 range. The Real SAAMI Specification for 44 Mag Throats is .4325.

The Anaconda shoots so well I need a new front sight so I can split hairs. I just got back from my northern range. Picture below, 7 am Sunday first 6 shots, with the 6" 629. Miha's 503 sized .431, 19g 2400, first shot high-right told me poi. The real surprise was 44 Specials. I had loaded 400 44 Specials with 14g of 2400 behind some NOE 429421s sizes .431 and just quit shooting them as they weren't accurate. NOT ANYMORE. I was late leaving the property cuz I was having so much fun linking holes at 20 yards with the "specials". I shot from 20 yards as there was no sun at 25 and it was cold. Still snow in spots at 3000 feet.

[750k2]

Do you go in from the front or rear of the cylinder?
Just trying to visualize before taking the plunge.
It wont be the first time if I booger it up.
I belong to the hard knocks school of smithing - It's half the fun:veryconfu

[Mal Paso]

The reamer goes in just like a cartridge and cuts toward the barrel.

I gotta think the small throats are there boost jacketed performance, which is the largest segment of the bullet market. However in every side by side test I've done with factory jackets against a proper fitting lead boolit, the lead averages 100 fps faster.

I got a sub 2" group today at 25y, offhand, with the 6" S&W 629 and those "Specials" ......six inches high and right. Gotta have something to work on.:bigsmyl2:
.

[leftiye]

400 grit sandpaper, a steel rod that is small enough to fit into the chamber mouths (not throats) with a couple of wraps of sand paper on it. Saw a slit lengthwise in the rod with a hacksaw to form a slit to hold the end of the sandpaper. Affix the sandpaper to the rod, chuck the rod into a hand drill motor. Insert into rear end of chamber (holding chamber in hand), and carefully work the sandpaper into the chamber mouth, and sand the chamber mouth out. If you've only got a thou or two (which is usually the case) the concentricity and cylindrical straightness will be fine. Use pin gauges to tell you when desired diameter is reached - CLEAN the chamber mouth well or your measurements will be off, and the abrasive will ruin your pin gauges.

[John Taylor]

When doing cylinders, keeping things strait is very important. I use to make cylinders for conversion and made up jigs for each size I worked on. http://i95.photobucket.com/albums/l132/johnptaylor/cylinderreaming.jpg
Another way to keep things strait was to make up a dummy barrel for a reamer guide. This insured the cylinder was lined up to the barrel. http://i95.photobucket.com/albums/l132/johnptaylor/reamingcylinder.jpg
Best would be to buy a chamber reamer with the throat you want. This would insure that the throat is lined up with the chamber. I get most of my reamers from http://www.pacifictoolandgauge.com/

[Mal Paso]

When doing cylinders, keeping things strait is very important. I use to make cylinders for conversion and made up jigs for each size I worked on. http://i95.photobucket.com/albums/l132/johnptaylor/cylinderreaming.jpg


Now I understand why the drill press. The Manson Reamer Has a Pilot Bushing which it follows down the throat and is not like the one pictured. The Manson Reamer doesn't require a shop, probably costs a couple bucks more with the pilots, and won't correct for an out of position cylinder as it is guided by the old bore. I did see some through the frame equipment like yours that would.

This is fascinating! Thanks for posting! I'll try to put some pictures up.

[leftiye]

You should probly fix out of position (out of time) cylinders with an oversize locking lug which is filed to correctly position the chamber mouths. Further, you should do this with the cylinder locked into proper position with a drill guide (as shown by John Taylor) of the same I.D. as your chamber mouths with a dowel in the drill guide and into the chamber mouths to hold the cylinder in proper position. Then fit the oversize locking lug.

This is great too - when making minimum chamber (tight) cylinders out of a smaller caliber cylinder- for locating the cylinder properly on the frame. Then go to the larger reamer size (and drill guide) to ream the chamber mouths. Clamp the cylinder and frame to stop the reamer from torqueing the cylinder out of position while reaming.

[Mal Paso]

Fascinating! But what you guys describe is a whole other level. The Manson Reamer really is a Hand Tool. I'll post a picture later, camera battery died and it won't take regular batteries.
I have no reason to believe I have timing issues just throats that WERE sized for jackets.

Thanks for all the info!

[Mal Paso]

This is the Manson Reamer.

[nanuk]

[QUOTE=leftiye;1271181]400 grit sandpaper, a steel rod that is small enough to fit into the chamber mouths (not throats) with a couple of wraps of sand paper on it. /QUOTE]



Wouldn't the "Mouth" be where the rim sits? as opposed to **** end where the business exits?

I've heard of the term "Throat" to refer to the boolit supporting end, but this is the first time I've noticed the term "Mouth" to refer to the same thing.

I sure wish there was standardized terminology to describe stuff. it would be easier for simpletons like myself to follow along

[tek4260]

If you only have one or two to do, use Cylindersmith

www.cylindersmith.com


Otherwise,

http://www.brownells.com/.aspx/pid=7700/Product/REVOLVER_CYLINDER_THROATING_REAMER

Also, cut the head off of an old case to make a sleeve to hold the rear of the reamer centered. Simply slide it up on the reamer where the tape is shown in the pic above.

[nanuk]

GREAT tip about the cartridge case acting as a bush

[Mal Paso]

I like 3/4" wide office tape. You want Nothing that stretches! It builds up .004 per lap so it's easy to get good fit. It stays put. 3/4" will cover the length of most throats. Measure so the tape enters the chamber before the cutters touch the throat. Loose enough, in the chamber, it doesn't bind. Slit it with a knife when you're done.

Actually I couldn't get the case the right size to work.

[750k2]

[smilie=w:
Just got done - Manson worked great - Just under .358 per pin gauges and they look
great.
Now I'm in the hunt for more .38's with small throats.
Did the old police positive come small:idea:

[Mal Paso]

Very Cool! Let us know how it shoots.