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mack1
10-13-2020, 10:39 PM
I am loading for an old black powder frame Colt Frontier Six Shooter (44-40). The cylinder throats are .426 and the barrel is close to .430, my question is why did Colt build them this way? I'm certain they knew how to make them shoot well.

Outpost75
10-14-2020, 04:25 PM
I have the same problem with mine. A curate 43-200QL has. .428 driving bands, large lube groove for SPG, and enlarged nose stop ring to size bullet to fit forcing cone of 1873 Winchester. Your revolver will be more accurate if you have Doug Guy hone cylinder throats to one half though over barrel groove diameter

Walks
10-14-2020, 04:39 PM
This used to drive my Dad NUTS.
Had a .44-40 with .427 chamber mouths and .425bore. A .38-40 with .400 chamber mouths and .399bore. They didn't shoot too bad, under 2 1/2" at 25yrds on a good day. Wish I still had them.
And a Cut down Calvary model with .454 chamber mouths and a .458bore, that one went away in a hurry.

Said it was always a gamble buying 1st gen SAA's. You could never find out what you had until ya got it home to measure everything.
I know He cried a bit inside when his favorite .45Colt was stolen, it had .453 chamber mouths and a .454 bore, sized COWW #454424 to .454 and it shot better than any SAA I've ever seen.

Chemoman
10-18-2020, 05:47 PM
very interesting post, the same holds true with the 45/70 trapdoor. different sizes of the bore. doug guy could make any old colt with this problem fixed easily. its the big cal rugers now who have that problem. i have quite a few revolvers and i redid the forcing cone on each one to perfection. all but the one ruger had good cylinders.

Silver Jack Hammer
10-20-2020, 01:10 AM
One the other hand I buy 3rd gens and want .44 Special Colt’s and the barrels can range .428“ -.427”. It’s like Colt’s will bore the barrel first and then decide what caliber to print on the side of the barrel, .44-40 or .44 Special.

I did have a 3rd gen that come from the factory with .430” cylinder throats and .429” barrel. It shot fine but it wasn’t that much more accurate.

I paid to have another cylinder custom bored to .430”. Waste of money. DougGuy is the ticket for accuracy.

mack1
10-20-2020, 07:41 AM
HI have watched a rifling machine run that came out of the Stevens plant from the turn of the century. The man that owns it can cut a 30 cal barrel to what ever i want so I know they could make a barrel whatever dimention they wanted.

DougGuy
10-20-2020, 09:04 AM
The 44-40 is somewhat of an anomaly in itself. Not because the barrel might be an odd size to call it a 44, but the bottleneck diameter pretty much dictates what the max diameter boolit you can use. Let's say I run a gage pin in your cylinder and the largest pin that fits the bottleneck part of the chamber is a .445" so measure the case wall thickness at the case mouth, let's say that measures .007" with a decent quality caliper, so double that, one case wall for each side, for a total of .014" and subtract from .445" leaves .431" but these won't normally chamber all the way in a cylinder with .427" or .425" throats.

Modern gun makers typically use the same barrel for all 44 caliber revolvers, most are .429" or .430" groove diameter. Shooting the old 44-40 through a .427" cylinder into a .430" barrel will have leading out the waz00 in a hurry.

The most practical thing to do is have the throats honed to at least groove diameter, or perferrably half a thousandth over, and use the biggest boolit that will fit in the bottleneck portion of the cylinder. I have found that for most purposes, honing throats to .4305" and using .430" boolits works quite well.

I do recommend using a softer more traditional alloy for the 44-40, and soft lube, even SPG for black powder works very well in smokeless powder loads.

The softer alloy will obturate and seal in the bore at a lower pressure than will a harder more typical alloy like COWW, and you CAN get away with using a cylinder with smaller throats and a soft alloy over a stout enough powder charge, as this will rapidly obturate and fill the bore for a fairly accurate and little or no leading experience with the 44-40.

I like the hone to fit method much better, it's more predictable and consistent.

Outpost75
10-20-2020, 09:40 AM
FWIW I had a Ruger Vaquero which came with .445" chamber necks, .425" cylinder throats and a .429 barrel.

I sent the cylinder to John Taylor for rechambering. His reamer opened the chamber necks to .448 and the cylinder throats to .4305". It now shoots "like a rifle" with .430 bullets.

My Hamilton Bowen .44-40 cylinder fitted to my Ruger Super Blackhawk is chambered the same way and shoots well.