New guy here, been looking around for a while but ran into a wall and need some help.
Took the rig out last weekend, looking for hits out to 1k. I knew I would need to true the measured MV to reflect real world performance because that's just how it goes. Zero was confirmed at 100 yards, calculations were solid at 782 yards (POI may be a tad low, mirage plays with me sometimes) but when I go out to 1,076 yards the data says to dial up 9.7 mils, and nothing. I do the stupid thing and dial up more thinking I must have mil'd the target too close, and still nothing. After an hour and multiple trips to the target and back I put the smooth brain away and decide to dial down to 8.7 mils, then fire off another at 8.2 mils. Next trip to the target shows 2 holes, spaced about 1/2 mil apart (ending up about .3 mils high of target waterline). "Okay, that's odd" I think to myself, but it be what it be and hits don't lie. I shoot a 3 round group to confirm at 8 mils then go home to reevaluate my life decisions and play with the calculator only to find out to adjust POI to reflect ~7.7 (where the waterline is) I have to adjust MV from 2697 to 2988! At this range my bullet is still supersonic, so I haven't adjusted BC, but in trying it just for the sake of fun I found out I'd have to move the BC from .301 to over .410, which simply can't be.
Where have I gone wrong? Scope tracks beautifully, so I don't think it could be that. Muzzle velocities are expected to be a little off, but not by THAT much! Please see below for all relevant data.
Rig:
Tikka T3 CTR .260 Rem
KGB Bravo (AICS Mags)
Harris 6-9" (that's what she said)
Vortex Viper PST Gen 2 (Leveled)
Weaver Rings & 20 MOA Base
Ammo:
142 gr Sierra SMK (1742C)
43.0 gr. Hodgdon H4350
CCI BR-2 Primers
Starline Brass
Base to Ogive @ 2.409" with an average OAL @ 2.027"
Magnetospeed V3 Avg MV @ 2697fps / 8.3 fps Standard Deviation
Weather:
D.A.: 4350
Station Pressure 26.16
55.2 Degrees American
25.5% Humidity
Thanks to anyone who can help out, I'm just confused.
Took the rig out last weekend, looking for hits out to 1k. I knew I would need to true the measured MV to reflect real world performance because that's just how it goes. Zero was confirmed at 100 yards, calculations were solid at 782 yards (POI may be a tad low, mirage plays with me sometimes) but when I go out to 1,076 yards the data says to dial up 9.7 mils, and nothing. I do the stupid thing and dial up more thinking I must have mil'd the target too close, and still nothing. After an hour and multiple trips to the target and back I put the smooth brain away and decide to dial down to 8.7 mils, then fire off another at 8.2 mils. Next trip to the target shows 2 holes, spaced about 1/2 mil apart (ending up about .3 mils high of target waterline). "Okay, that's odd" I think to myself, but it be what it be and hits don't lie. I shoot a 3 round group to confirm at 8 mils then go home to reevaluate my life decisions and play with the calculator only to find out to adjust POI to reflect ~7.7 (where the waterline is) I have to adjust MV from 2697 to 2988! At this range my bullet is still supersonic, so I haven't adjusted BC, but in trying it just for the sake of fun I found out I'd have to move the BC from .301 to over .410, which simply can't be.
Where have I gone wrong? Scope tracks beautifully, so I don't think it could be that. Muzzle velocities are expected to be a little off, but not by THAT much! Please see below for all relevant data.
Rig:
Tikka T3 CTR .260 Rem
KGB Bravo (AICS Mags)
Harris 6-9" (that's what she said)
Vortex Viper PST Gen 2 (Leveled)
Weaver Rings & 20 MOA Base
Ammo:
142 gr Sierra SMK (1742C)
43.0 gr. Hodgdon H4350
CCI BR-2 Primers
Starline Brass
Base to Ogive @ 2.409" with an average OAL @ 2.027"
Magnetospeed V3 Avg MV @ 2697fps / 8.3 fps Standard Deviation
Weather:
D.A.: 4350
Station Pressure 26.16
55.2 Degrees American
25.5% Humidity
Thanks to anyone who can help out, I'm just confused.
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