1874 Sharps at 600 yds, pure success !

So this morning was the testing of BPCR at my clubs 600 yd range. Thus far i've received some elevated pushback about attempting 600 yds at my club. The concern was the fact at the base of our impact berm is built up with vary large rocks to stop sand erosion down the 30 degree angle. The concern was for bullet impacts and ricochets possibly injuring our manned target pullers. Happy to report all my hard work of calculations and trajectory comparisons, payed off and long story short, the 45-70 caliber is only impacting about 12" lower versus a typical supersonic 308 at 600 yds. Myself and 4 other seasoned mid range shooters tackled the task of testing and spotting shots for safe impacts within our berm. I shot very well considering i'm fairly new to BPCR. I loaded up using BACO's 545 Creedmoor boolit, and 68 gr of Swiss 1.5F and i was at about 1244 fps average with a SD of about 10 fps. This is about a 3.5 MOA load at 200 meters for me. We shot at a standard NRA MR target and my initial 600 yd shot was a 8 ring score at 12:00. My issue is I was not 100 % exact on my dope calculations as I'm using the MVA 5x scope with the micrometer turrets. I had to deviate from the suggested mount bracket mount distance to obtain correct eye relief so in doing so that throws off your MOA click graduation increments. The theoretical .5 moa per graduation actually worked out to about .48 moa. More time spent testing come-ups will fine tune this number. All in all i'm extremely happy the day of testing went off well. All my shots were well "within the black" scoring rings, so moving foward now it's time to test different loads.