I have a 5” Blackhawk Bisley. Normally I shoot heavy loads through it like 265gr at 1200fps.
Looking to do either 255 plated or 255 hard case lighter loads that shoot with the same front sight….ideally
Blackhawk, the one with adjustable rear sight, not the Vaquero with a fixed rear sight, right??
Front sight isn't going to matter much, factory original should be fine. Difference in point of impact with lighter loads should be within the adjustment range of your rear sight.
So, what should I work up for plinking?
Depends on what level of load you want to plink with. There are roughly three general load levels common these days. (and I'm not talking in detail about the Tier I, II, & III pressure levels yet.)
Generally speaking the common load levels are, the original black powder load level /smokeless equivalent (a 250gr slug around 800-850fps +/- depending on barrel length), the cowboy action load level, which is lighter than the original BP level, and then everything heavier than the original BP level velocities, either by a little, or a lot.
If you're used to shooting 265gr @ 1200, you'll be amazed at how light the standard BP level load is going to feel. Might just be your "perfect" plinker.
Cowboy action loads are lighter, some 100fps less than standard ammo, they're made for that game, with light loads to minimize recoil saving time which matters in the game.
For me, they are too light. Gun goes "pop" and I feel like I should be checking the barrel to make sure the bullet came out. I want a load with enough recoil to be felt, and be fun even when plinking. For ME, the point of shooting an SA revolver in .45 Colt is to shoot one in .45 Colt, not shoot a cat sneeze target load. But that's just me...
Of the powders you have, the only one I am even a little familiar with is AA No.5, and it is a fairly fast powder, full pressure loads don't fill the .45 Colt case all that much, so its important to check case fill closely to make sure a double charge doesn't get a bullet and get loaded. A slower powder fills the case more, and makes a double charge more easily seen and the very slowest pistol powders double charge would overflow the case.
Even Rugers can be blown up if a double charge happens and gets past your check and becomes a loaded round. Not likely, but not impossible, so be careful.
Same warning applies to all large cases using the small charges fast burning powders require.
If you can, I recommend you get some Unique. I've used nothing but Unique in the .45 Colt for the past 40 years. Some say it burns too dirty, some say it doesn't measure smoothly enough. To which I say, "so??" I shoot cast 250gr SWC its going to be dirty no matter what. Meters smoothly enough for me.
For about the last 35 years or so, I've only been loading one load in my Ruger .45 Blackhawk, 10.0gr Unique under a 250gr cast SWC. Clocks just a bit under 1100fps from my 7.5" barrel gun so that puts it a bit above standard factory ammo in speed. Recoil is "stout" but not uncomfortable for me, (plus I use Pachmayr grips), its fun to shoot, accurate, and has plenty of "thwop" when it hits.
Its my "one load to rule them all" thing, which I use for plinking and everything else. Had my years of turning the .45 Colt into a match for the .44 Mag, (in RUGER guns) settled on a good stout load less than .44mag levels but a little bit above standard .45 Colt.
The advantage to only using one load is once you learn it, You're there. Every time you shoot the gun is going to be shooting the same. No worry about a change in the POI due to a lighter or faster bullet.
With my chosen load and now decades of practice, I know exactly where to hold to hit what I want hit at range 0-200yds.
one of the joys of Ruger Blackhawks in .45 Colt is that you can shoot anything from "cat sneeze" to "Dragon roar" level loads and the only thing you might need to do is adjust the rear sight.
So, just decide what general level of load you want to plink with, and load a few test rounds and see if its what you're looking for.
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