With the tight choke he is using, I don't think buffer will help much. I load #1 buck, in 3" loads, using MM wads, and add buffer(BPI load data). But I am thinking I probably don't have to. I do play around with unslit MM wads, and have tried not cutting any slits, which kind of turns it into a slug, for 30 yards, before the wad finally trails away from the pellets... I have been cutting little V shaped wings in the wads, to act as air brakes, for both buckshot(MM Wads), and tungsten turkey loads(TPS Wads), and that seems to help with more pellets on target at extended ranges. I am guessing the unslit wads tumble chaotically, which doesn't let all of the pellets exit uniformly. Cutting the air brake V's, seems to stabilize the wad until the pellets/shot exit. I have pre-slit wads too, but I seem to get better pattern density with unslit wads, with my custom V-wing slits. I don't usually shoot 12 ga. buckshot patterns beyond 50 yards, for buckshot. I guess I should see how my loads do. My 12 ga. buckshot loads are for self-defense mostly.
I did load some 10 ga. buckshot loads, that do look nice and dense to 60 yards, but I haven't gotten my Browning Gold 10ga out for coyotes recently.
Squeeze
P.S. One thing to mention, tighter chokes don't always mean tighter patterns, with buckshot, or tungston turkey shot. In some cases with BPI wads, I have found modified or just plain old full, gives tighter patterns, rather than the extra or extra extra full chokes. So definitely play around with more open chokes, if one tries the full length BPI TPS wads(MM wads are discontinued
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