+1 for the Handloads.com ballistic calculator. I use it for all of my weapons. If you use a 25 yard range, just figure your load zeroed at 75, and have it print the appropriate distance above POA at 25. With the load you describe, 2" above POA at 25 would put you on at 75. My Marlin 44-40 Century Limited I load to about 1250 fps, and sight at 75 dead on POA. That translates into 1.25" high at 25. That puts it 3 inches low at 100 yards. Now for my 1900+ fps 200 JSP Taffin hunting load (Marlin 94 and Winchester 92 ONLY) load, I sight at 100 yards, which is 3/4" high at 25 yards. It should be a deer and hog thumper, with still over 1000 ft lbs of energy at 100 yards.