TC's recommended factory loads for it...
 
65gr .350 patched RB, 40-60gr of FFFG for approx 1900-2150 MV, 520-670 ME
 
128gr MaxiBall (lubbed) 40-60gr of FFFG for approx 1760-2000 MV, 890-1150 ME
 
In actual use 15-60gr Goex FFFG (reduced a little if Swiss), probably a .015" patch for the RB (depending on what the mold throws), and shoot to find what combo's your particular rifle likes for your uses.    You can vary patch thickness, but I wouldn't push the powder much higher like I can in my TC Hawken 36.  They are capable much farther than the 50 yards commonly printed for them, over twice that in perfect conditions, especially if sighted for a longer PBR.  
 
Have fun, nice find.
 
 
 
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