Correct bullet size for 3rd gen. SAA?

[jphendren]

I have a 3rd gen. Colt SAA that I bought new in 1997.  I am going to be ordering another couple boxes of Goex 45 caliber bullets for loading with black powder to shoot in this revolver.  They offer them in both .452 and .454" diameter.  Would the .454" size be a better fit for a 3rd gen.?  I have read that their cylinder throats are usually .455" or so.  Would the larger size help reduce leading?

Jared

[Trailrider]

Although the barrels in the 3rd Gen Colt's have been nominally set at .451-.452" groove diameter, you will probably obtain better accuracy from bullets that most closely fit the chamber throats, which tend to run larger.  I would suggest obtaining a couple of different sized bullets, or even soft lead round balls in .452 and .457.  Drive them through each chamber throat from the rear, using a wooden dowel and a padding of some sort so you don't ding up the front of the cylinder.  (Remove the cylinder from the gun to do this.)  Measure these bullets and see what size the throats are.  Then I'd go .001 over the throat diameters.  If you don't get decent accuracy, you can try smaller or larger bullet sizes.  If you can't do this, then I'd go with the larger bullets and see what happens.  No, you won't blow the gun if the bullets are slightly oversized.  The only possible problem you might encounter with bullets that are too large is whether the cartridges will go into the chambers.

Hope this helps.

[Fox Creek Kid]

...Then I'd go .001 over the throat diameters...

Scientifically impossible. Your best bet is to go chamber throat diameter for bullets.

[jphendren]

From what I have read, most modern Colt's have a .451" groove diameter, and .455-.456" cylinder throats which is not ideal.  I have been shooting .451" Goex 235gr bullets from Powder Inc.  They seem to shoot pretty well, but on this last trip my cylinder and barrel took some heavy leading.  So I am not sure if it is because the bullets were undersized allowing hot gas to pass the bullet melting the driving bands, or if it is a lube issue.  Powder Inc. only offers the Goex bullets in two sizes, .451" and .454", which is still too small for a modern Colt cylinder.  I have not measured the throats on my Colt as of yet, but will do so when time permits.

I read a threat elsewhere, where someone asked Colt to build them another cylinder with a removable bushing, and with .452" throats.  Colt did this for free, however, the throats were still the standard .455".

Jared

[Fox Creek Kid]

From what I have read, most modern Colt's have a .451" groove diameter, and .455-.456" cylinder throats which is not ideal.  I have been shooting .451" Goex 235gr bullets from Powder Inc.  They seem to shoot pretty well, but on this last trip my cylinder and barrel took some heavy leading.  So I am not sure if it is because the bullets were undersized allowing hot gas to pass the bullet melting the driving bands, or if it is a lube issue.  Powder Inc. only offers the Goex bullets in two sizes, .451" and .454", which is still too small for a modern Colt cylinder.  I have not measured the throats on my Colt as of yet, but will do so when time permits.

I read a threat elsewhere, where someone asked Colt to build them another cylinder with a removable bushing, and with .452" throats.  Colt did this for free, however, the throats were still the standard .455".

Jared

Actually Colt will NOT do this as the original cylinder falls into SAAMI specs. What people who are serious shooters do when faced with this problem is buy a Colt .357 cylinder & have it rechambered to .45 Colt with proper throats to match their specific groove diameter.

My Colt FSS throats were undersized by a hair so I had the chambers & the throats opened up a tad by a ´smith with a 44-40 reamer made to his specs as well as a 0.431 finish reamer. Shoots ragged holes now. 

[Trailrider]

Scientifically impossible. Your best bet is to go chamber throat diameter for bullets.

Hunh? How is it impossible to go .001 over throat diameter?  I shoot Ruger Old Model Vaqueros in .44-40 and I shoot .430" bullets, and the throats are .425"! With hard cast bullets the slugs are squeezed down and then re-expand on leaving the throat.  The problem with going .001 over throat diameter is if the throats are SO large that you can't chamber the rounds.  I HAVE had that problem with the original cylinder chambering in the .44-40 Rugers.

[Sagebrush Burns]

Shooting smokeless loads in my Colts (45 Colt caliber) I have tried both .454 and .452 bullets and noticed no appreciable difference in accuracy or barrel leading.  My experience would lead me to believe that lead hardness and soft lube would be more important than bullet diameter.

[Fox Creek Kid]

Hunh? How is it impossible to go .001 over throat diameter?  I shoot Ruger Old Model Vaqueros in .44-40 and I shoot .430" bullets, and the throats are .425"! With hard cast bullets the slugs are squeezed down and then re-expand on leaving the throat.  The problem with going .001 over throat diameter is if the throats are SO large that you can't chamber the rounds.  I HAVE had that problem with the original cylinder chambering in the .44-40 Rugers.

Trailrider, on many 44-40 revolvers the problem is the finish reamer and not just only the throat diameter as SAAMI specs for the 44-40 are very ¨wide¨. Also, you´re bullets are not very hard if you´re able to swage them down 0.0025 (either side) by thumb pressure and as such you are not really shooting an oversized bullet as you yourself have stated that you are ¨swaging¨ the bullets down upon chambering.

On another note, it´s wise to allow 0.0005¨ - 0.001¨ for fouling if you´re doing CAS style shooting. Especially real BP. That´s why I shoot soft bullets sized to 0.430¨ in a 0.431¨ throat.