Same here ... 870 with Hastings rifled barrel .... 12ga ...
The Federal Power Shok seemed to be the most accurate out of my barrel ... so that's what I am shooting ... and they are relatively inexpensive ... and I get 2 1/2 inch groups at 100 meters ...
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Federal F127 SS2 Power Shok - Sabot Hollow Point - 1500 fps - 1 oz
Zeroed at 100m --> 1.66 Inches High at 50m
Zeroed at 100m --> -2.21 Inches Low at 120 Yards
Zeroed at 100m --> -7.47 Inches Low at 150 Yards for
Zeroed at 100m --> -22.55 Inches Low at 200 Yards
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Sighted in at 100 meters.
And I am not shooting further than 120 meters ... and with that my setup shoots 2 inches high at 50 meters or 2 inches low at 120 meters. So, all those shots are still in the boiler room .... and no need for crazy calculations or fancy reticles ....
If you want to know the drop for your ammo:
http://spoton.nikonsportoptics.com/spoton/spoton.html
I still haven't tested the Remington AccuTips out of this barrel .... if they group well, the ballistics would be a bit better:
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Remington AccuTip 12ga 2 3/4"
Zeroed at 100m --> 0.95 Inches High at 50 Yards
Zeroed at 100m --> -1.54 Inches Low at 120 Yards
Zeroed at 100m --> -5.66 Inches Low at 150 Yards
Zeroed at 100m --> -17.13 Inches Low at 200 Yards
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Remington AccuTip 12ga 3"
Zeroed at 100m --> 0.86 Inches High at 50 Yards
Zeroed at 100m --> -1.44 Inches Low at 120 Yards
Zeroed at 100m --> -5.34 Inches Low at 150 Yards
Zeroed at 100m --> -16.24 Inches Low at 200 Yards
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