ScottZ
Single-Sixer
What diameter bullet would you guys recommend starting with?
.45 Colt - What diameter should I start with?
- Thread starter ScottZ
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Ia.redneck
Bearcat
.452 is most common. Try to measure the exit holes on your cylinder and go with that or .001 bigger. 
ScottZ
Single-Sixer
Thanks
Lost Sheep
Single-Sixer
Thanks for asking our advice.
You see, whatever size bullet you start with, if it is larger than your the exit hole of your cylinder's chambers (the throat) it will wind up being sized down to the size of THAT CHAMBER's throat. Note that not all chambers may be exactly the same size, including the throat.
If your throat is the same size as the bullet, good. If the throat is larger than the bullet, there will be some blow-by of hot gasses and burning powder as the bullet exits the chamber throat and enters the barrel's forcing cone. Bad, but not disastrous. If your throat is substantially smaller than the bullet's diameter, you may get higher pressures than you would if they were more closely matched. This may result in overload pressures (check for signs of pressure) or merely higher velocity with no substantial drawbacks. This is one reason we start low and work up loads carefully.
If your bullet (however it came to be the diameter it is) is smaller than your barrel's bore (the grooves) you are likely to have leading and poor accuracy. Hot gasses blowing by the bullet tend to melt the sides of lead bullets and leave the lead on the inside of the barrel. If you bullet does not get the proper spin from the rifling or gets off-center in the barrel, accuracy will suffer.
These principles apply to all revolvers, but are an issue mostly with 45 Colt because it is the most popular surviving caliber from the black-powder and percussion revolver days. .454" was the normal diameter for the bulk of the century from the 1860's (or thereabouts) through the early to mid 1900s. After that, .451" became more popular and now is very nearly the norm.
If you slug your barrel and measure your chamber throats for your revolver, you will know for sure. Reaming chamber throats to match your barrel is fairly easy to do if you have the tool and a gunsmith should do the job for a reasonable price. Then you will know for sure what bullet size you should get.
I hope this clears up the "whys" and "hows".
If your gun is of fairly recent manufacture, .452" for lead and .451" for jacketed is 90% sure to be right (my guess on the percentage). If you can push a .452" through the chamber throat easily, maybe you should try a larger bullet. Go into your gun store and ask if you can try that with their bullets.
It is polite to ask BEFORE you bring the gun into the store. Better still, if it is a single action, go in with only the cylinder.
Lost Sheep
IA.Redneck is right.ScottZ said:
You see, whatever size bullet you start with, if it is larger than your the exit hole of your cylinder's chambers (the throat) it will wind up being sized down to the size of THAT CHAMBER's throat. Note that not all chambers may be exactly the same size, including the throat.
If your throat is the same size as the bullet, good. If the throat is larger than the bullet, there will be some blow-by of hot gasses and burning powder as the bullet exits the chamber throat and enters the barrel's forcing cone. Bad, but not disastrous. If your throat is substantially smaller than the bullet's diameter, you may get higher pressures than you would if they were more closely matched. This may result in overload pressures (check for signs of pressure) or merely higher velocity with no substantial drawbacks. This is one reason we start low and work up loads carefully.
If your bullet (however it came to be the diameter it is) is smaller than your barrel's bore (the grooves) you are likely to have leading and poor accuracy. Hot gasses blowing by the bullet tend to melt the sides of lead bullets and leave the lead on the inside of the barrel. If you bullet does not get the proper spin from the rifling or gets off-center in the barrel, accuracy will suffer.
These principles apply to all revolvers, but are an issue mostly with 45 Colt because it is the most popular surviving caliber from the black-powder and percussion revolver days. .454" was the normal diameter for the bulk of the century from the 1860's (or thereabouts) through the early to mid 1900s. After that, .451" became more popular and now is very nearly the norm.
If you slug your barrel and measure your chamber throats for your revolver, you will know for sure. Reaming chamber throats to match your barrel is fairly easy to do if you have the tool and a gunsmith should do the job for a reasonable price. Then you will know for sure what bullet size you should get.
I hope this clears up the "whys" and "hows".
If your gun is of fairly recent manufacture, .452" for lead and .451" for jacketed is 90% sure to be right (my guess on the percentage). If you can push a .452" through the chamber throat easily, maybe you should try a larger bullet. Go into your gun store and ask if you can try that with their bullets.
It is polite to ask BEFORE you bring the gun into the store. Better still, if it is a single action, go in with only the cylinder.
Lost Sheep
If a late model Ruger the correct bullet should be .452 cast. Earlier (pre-80s), all bets are off (believe .454 is usually necessary). If you can press the .452 sized bullet into the cylinder throats with finger pressure then you good to go. They should NOT fall through but need just a bit of pressure. If you feel you have to hammer them in with a sludge ... then the throats need reamed to .4525. Simple test. Note that you should get a bullet of the right hardness to. For most .45 Colt loads a BHN of 12-15 are good. This allows the pressure to bump up the bullet size to fill the throat to seal the bore and not allow gases to get by the bullet (cause leading as said above).
Barrels from Ruger I believe are quite consistent size wise. Only thing you might run into is a constriction which also cause leading because a constriction squeezes the bullet down and when it passes the constriction it allows hot gases to again get pass the bullet. As said above leading occurs and accuracy suffers. More common on .44 and .45 barrels where the barrel is threaded to the frame. Fire lapping or Taylor throating can cure this problem. Easy to tell if you have constriction if you run a pure lead sinker down the bore. Once tapped into the bore it will go down the bore quite easy ... until you hit a constriction. Then it takes just a bit more tapping to get it pass the constriction.
Hope that helps.
Barrels from Ruger I believe are quite consistent size wise. Only thing you might run into is a constriction which also cause leading because a constriction squeezes the bullet down and when it passes the constriction it allows hot gases to again get pass the bullet. As said above leading occurs and accuracy suffers. More common on .44 and .45 barrels where the barrel is threaded to the frame. Fire lapping or Taylor throating can cure this problem. Easy to tell if you have constriction if you run a pure lead sinker down the bore. Once tapped into the bore it will go down the bore quite easy ... until you hit a constriction. Then it takes just a bit more tapping to get it pass the constriction.
Hope that helps.
