Yep, that one.original Deerstalker semi-auto rifle
I may have ended up with that turkey. For sure I had one like it, briefly. I did some programming work for a gun store in the late ‘90’s and bought a later ‘80’s 44 Carbine. Cause it was cool. It was also a jamamatic. Sold it back a month later. It turned out to be something minor that Ruger fixed for free but by then I’d moved on. I never tried it with handloads since it was jamming on factory so I can’t help there. H110 and a Sierra 240gr JHC sounds like a good plan to start, though. I do remember those guns came with a warning not to use lead. It clogs the gas port for some reason.Not all of the carbines shoot the same in my experience though.
My first carbine was a very early mint gun that just didn't take to any load I tried,
so down the road it went (to a collector
I've tried 180,200 and 240gr Hornady XTPs with H-110 and WLP they functioned well but the POIs were quite different mostly in elevation. The 240gr XTP with 24.0gr of gave a average of 1,795 fps, the 200gr XTPs averaged 2,082 fps with 28.2gr of H-110 I didn't get numbers on 180sLoading 23.5 grs. H110 under the 240 jacketed soft points