NM Blackhawk Flat top.45acp/.45LC Cylinder throat size?
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George
Blackhawk
Link is still mot working fo me!
George
Blackhawk
Yep link is working now! Great work! GeorgeDougGuy said:
Most 45 Colt cylinder throats are opened to .4525". Many jacketed bullets are made at .452". Most of the old timers cast their Colt, or Colt clone bullets from a .454 mold and sized at .454 or .453". Some of the newer guns shoot cast sized at .452" just fine. My Vaquero does.
Size of cylinder throat does make a difference. I have a DW .357 that I used in competition. Every once in a while I would get a flier. One day I marked each cylinder with a marker and shot once at each of 6 targets. I went through 5 times and compared the 5 shot groups. It was easy to find the cylinder that was spitting the fliers. I marked that cylinder with black sharpie, and then went through again. I wanted to confirm EXACTLY where point of impact was in relationship to center of target for each of the other cylinders, and as the gun got lighter. It was surprising how much that gun moved as it got lighter 220 grains at a time.
Hope this helps.
Steve
Size of cylinder throat does make a difference. I have a DW .357 that I used in competition. Every once in a while I would get a flier. One day I marked each cylinder with a marker and shot once at each of 6 targets. I went through 5 times and compared the 5 shot groups. It was easy to find the cylinder that was spitting the fliers. I marked that cylinder with black sharpie, and then went through again. I wanted to confirm EXACTLY where point of impact was in relationship to center of target for each of the other cylinders, and as the gun got lighter. It was surprising how much that gun moved as it got lighter 220 grains at a time.
Hope this helps.
Steve
George
Blackhawk
Shaggy357 said:Most 45 Colt cylinder throats are opened to .4525". Many jacketed bullets are made at .452". Most of the old timers cast their Colt, or Colt clone bullets from a .454 mold and sized at .454 or .453". Some of the newer guns shoot cast sized at .452" just fine. My Vaquero does.
Size of cylinder throat does make a difference. I have a DW .357 that I used in competition. Every once in a while I would get a flier. One day I marked each cylinder with a marker and shot once at each of 6 targets. I went through 5 times and compared the 5 shot groups. It was easy to find the cylinder that was spitting the fliers. I marked that cylinder with black sharpie, and then went through again. I wanted to confirm EXACTLY where point of impact was in relationship to center of target for each of the other cylinders, and as the gun got lighter. It was surprising how much that gun moved as it got lighter 220 grains at a time.
Hope this helps.
Steve
Steve, New model Vaquero? Do you know the throat size of that cylinder? .45colt? Just wondering how close it is to the size of my NM Mid frame flattop .45colt cylinder. Yes what you say makes sense. How I see what your saying! As the gun get's lighter as you shoot you run into the chamber with the tight cylinder you get more recoil not only from lightening your load of 220 grain bullets but you get to the tight cylinder and also get more recoil from that and that will throw your shot off a bit. I would think that if the gun was put on a lead sled and recoil was taken out of the equation that flier would hit a lot closer on the target. My guess is that the barrels lands and groves it's size has a lot more to re stabilize that bullet then any other factor. am I seeing this right? Thanks! George
I have said over and over that how EVEN the throats are is more important than their diameter. You can always size to fit the throats.
Uneven throats cause variations in pressure which greatly affects the recoil impulse felt by the shooter. Tighter throats develop more pressure which causes the gun to recoil differently in the shooter's hands, and the boolit will often shoot to a different point of impact than the same load fired from a loose chamber, using the same point of aim.
I try to get throats within .0002" of each other before they leave my shop, I use Z minus pin gages in half thousandth increments and you can tell from the feel of the gage pin when throats are even. This is what I try for and it works quite well.
Factory throats for Ruger single action revolvers don't adhere to any explainable time line or period or even model to model. Most of the 45 caliber throats are in the .4505" to .452" range, with the trend to generally be near .451" on average. I report this as I use the .451" pilot most, and the .4505" pilot is a close second for hundreds of cylinders reamed. Medium frame models seem to be more consistent, most of these are right at .451" which still does not facilitate using .452" bullets without sizing them down to throat diameter as they are fired.
Uneven throats cause variations in pressure which greatly affects the recoil impulse felt by the shooter. Tighter throats develop more pressure which causes the gun to recoil differently in the shooter's hands, and the boolit will often shoot to a different point of impact than the same load fired from a loose chamber, using the same point of aim.
I try to get throats within .0002" of each other before they leave my shop, I use Z minus pin gages in half thousandth increments and you can tell from the feel of the gage pin when throats are even. This is what I try for and it works quite well.
Factory throats for Ruger single action revolvers don't adhere to any explainable time line or period or even model to model. Most of the 45 caliber throats are in the .4505" to .452" range, with the trend to generally be near .451" on average. I report this as I use the .451" pilot most, and the .4505" pilot is a close second for hundreds of cylinders reamed. Medium frame models seem to be more consistent, most of these are right at .451" which still does not facilitate using .452" bullets without sizing them down to throat diameter as they are fired.
