IMO If you can keep most of your shots within the "8" ring on a sillouette target at 7 yards with a draw and fire, it should be good enough for SD. That contains most of the vital organs you want to hit.
I've also heard you don't really need a tight group in a SD situation (probably not going to acheive that anyway with the adrenalin flowing) You want to spread the shots out and hit more vital organs so the perp bleeds out quicker. That's just what I read, and made sense to me. You do want an accurate weapon capable of tight groups. It's nice to be able to draw quickly and place a shot on a playing card, takes practice though. I don't think I can do that very quickly. And certainly not in a situation. It seems that a lot of people are lucky to hit anything when the adrenalin kicks in, from looking at police car videos and and hearing about gang bang shootouts where they find like 20 spent cases and maybe 1 person was wounded.
Tom
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