I've done a bunch of reloading over these winter months (retirement is great). Even my 357 Maximum.

I bought the Ruger about 10 years ago. We shot it some when I first got it but that's about it. I loaded some IMR4227 and WW296 with Hornady 180 XTP using both CCI BR4 and Rem 7 1/2 primers. Last week it was 58° here in E. KY so decided to do some chrono and grouping. Thought I would share some results.

180 Hornady 180 XTP, Remington brass, 19.1 grs IMR4227, 1.988 OAL:
Rem 7 1/2= 1444 fps, SD 9
CCI BR4= 1390 fps, SD 16

180 Hornady 180 XTP, Remington brass, 18.0 grs WW296, 1.988 OAL
Rem 7 1/2= 1564 fps, SD 16
CCI BR4= 1549 fps, SD 20

The target analysis is performed using OnTargetShooting.com software. Neat program. Chronograph is a MagnetoSpeed
The difference in BR4 and 7 1/2 velocities is something I've noticed with .223 loads as well.

---