So I bought my boy a 20ga mossberg combo gun it come with a turkey and slug barrel. I put a red dot on it and bought a hs undertaker .572 what r the best shells for this combo. I bought mag blends but ur not suppose to shoot out of this choke I guess. I would like to use this gun also this year. Help please
Mag Blends from EM aren't doing so hot in the 20ga. Try Straight 7's from Fed, EM or Nitro unless you reload then TSS would be the option. I'm not familar with the HS Undertaker choke. Is it ported? Does it say no steel or no heavy shot? I have put 50-75 tungsten based loads through my 'lead only' RSF choke without a problem.
CB
For a start I suggest Federal FC #6 lead for the turkey gun and definitely Federal TruBall slugs for deer. Be sure to pattern this set up as I expect good 30 yard patterns OK 35 yards and not acceptable at 40 but you have to find out.
The Undertaker 582 is for hevi-shot. I personally feel that you are safe with the HTL #7 loads in your 572 choke. Many of the Rem Super Full chokes being used for HTL loads clearly state for lead shot only.
the Undertaker .582 is too open of a choke for me
I got one for my 870 youth and the patterns were just to open for me
My Beretta 391 Urika puts 145 Hevi-13 7's into a 10" circle at a lasered 40 yds using an Undertaker .582 choke. I have a Tightwad .570 that puts 158 into the same circle at 40 yds but it's not as even a pattern as the Undertaker.
TSS 9X8's thru my Undertaker pattern very well in my Benelli M1 20ga. If you reload, I'd give those a try.