We are lucky to live in a time when so much of 45 Colt load development has been done for us. I adopted one of Linebaugh's personal loads long ago, 13 grains of HS6 with a Missouri Bullet 255 SWC for 1045 fps from a 5 1/2" Ruger Vaquero. I checked its velocity with the 4 5/8" Vaquero and once around the cylinder, the numbers look like this:

Temperature: 81 Degrees
Distance: 6 feet
Average Velocity: 1055 fps
Extreme Spread: 54.09 fps
Standard Deviation: 19.39 fps
Chrony BetaMaster II

Considering that you are dealing with six different chambers here, the ES and SD numbers ain't bad at all. This 4 5/8" Vaquero, which has a tight barrel/cylinder gap, even gave 10 fps more velocity than my old 5 1/2" gun- but the short Vaquero printed it a full 10"high with it at 65 yards. Not close enough for a hunting revolver.

Next, I tried an old standby load for modern single action revolvers, consisting of 8.0 grains of HP38 (or W231) and a 255 grain SWC. This is one of those loads you will see in articles by reputable gunwriters, but you won't find it in the powder companies's manuals. I tried it because I wanted something that still hit with authority, but shot lower than the 13.0 HS6 load mentioned above.

From the short Vaquero, the HP38 load produced an average of 883 fps, with an extreme spread of 41.13 fps and a standard deviation of 15.71 fps. Excellent numbers all around; except it grouped about a 10" at 65 yards from this gun and hit about a foot low. Well, shizz... just goes to show you can't take anything for granted.

Back to the drawing board. I decided to split the difference and try 12.5 grains of HS6 with the Missouri Bullet 255 SWC. I was hoping it would slow the load down enough to move the POI down, without compromising the accuracy of the 13.0 grain load. It worked out real well, too. Six shots at a nut can lid from 65 yards. My right shoulder is giving me grief so I fired left hand, semi-supported over the range bag.

I believe the two rounds on and near the lid are what the gun is doing. The low/left round was me touching it off early and the one 3" left was just my screw-up. But the four best shots tell the story as far as accuracy potential and zero confirmation in this handy fixed-sight revolver. It's a great little sixgun by any standards.

I didn't have time to chrono the 12.5 load today, I'll check it when time permits and report the actual velocity. I'm betting it's right at 1000 fps which is plenty to drive SWC's through grass-munchers.