Conical Bullet For Ruger Old Army Revolver.

[Turnup]

The Ruger Old Army has a 1:16 twist rate. Uberti have also gone to this now. Pietta and older BP revolvers have a 1:30 rate.

All ROAs have the same twist rate? Mine is approximately 1 in 38" as near as I can measure it.

[loiner1965]

All ROAs have the same twist rate? Mine is approximately 1 in 38" as near as I can measure it.

will check my 1992 pietta now

edit.....tricky to do on a revolver but mine looks like 1 in 32 twist which seems right

[simgre]

All ROAs have the same twist rate? Mine is approximately 1 in 38" as near as I can measure it.

Yes, I believe they all have 1:16”. This is due to when deigned, Bill Ruger wanted to use as much of the Blackhawk model for ease of parts inventory and chose to use .45 Colt barrels from the Blackhawk for the OA.

This is also why the ROA uses .457 ball over the standard .454. The groove diameter of the 45 colt barrel is .452 and its said that optimum ball to bore fit is two thou over groove diameter. So by the time the ball has passed through the forcing cone it needs to be .454. But, you also need to have shaved the circumference of the ball to seal the chamber. A .454 ball doesn’t allow both events.