I shoot 2 3/4" #6 steel about 90% of our hunts.
I was pumped when dunns had these on sale for 169/case plus the $50 rebate. 11.90/box to the door. #6 hevishot at 1500 fps is some bad stuff!!
Your still shooting #6 steel, not #6 hevishot. The #6 on the box is the size of the steel shot in the duplex load. The hevishot ballistic equivalent shot portion in that load is probably around a #8 9.8gcc hevishot. Or smaller if they are using a pellet more dense than the old hevisteel pellets. But whatever pellet they are using, it is still supposed to be a ballistic match to #6 steel. Know too they use a wad that is not cut all the way. At least they were last time I cut one open, so unless your using a wad stripping choke, you should see a very tight black cloud type pattern at teal decoying distance.
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