Ruger blackhawk 45 colt,shooting 315gr Kieth style bullet @ 1050fps through a 4 5/8" barrel hits 8" high.Front sight is .335".How much higher does the front sight need to be to hit 2-3" high or my rear sight is bottomed out how much would I need to take off?

Cotton,

Is this "the" only load that you intend to shoot out of this Blackhawk? My 1st thought is "not" to make permanent alterations to the revolver just for the sake of dialing in that particular load.

??

Renster

To be honest, there is no way to tell, exactly. Shooter's grip has as much to do with elevation as do the sights on those plowhandles, especially the shorties.

What distance? I wouldn't think more than 1/16" would be needed.

Doin' a JB Weld build-up?

http://www.bowenclassicarms.com/PastPress.html

Read Bowen's article "site crankin" it very specifically tells you how to mathematically figure out how much more sight you need. I would suggest retesting your load with the rear sight NOT bottomed out more in the middle of the adjustment range. If you figure it bottomed out then a heavier bullet like a 335gr or 365gr would create the same problem for you later.