Each gun will shoot differently but my Ultra Elite love the Hornady 200gr SXT. When I first got it, I bought a box of a variety of bullet sizes and brands from 165gr to 230gr and the SXT was a clear winner. As there will never be a clear winner in the "small and fast" versus the "big and slow" debate, I'm guessing that the middle of the road 200gr isn't a bad compromise. Whatever you decide to use, make sure to run at least 100 rounds through it to ensure reliability. If it gags on even one round, it's not acceptable.
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My idea of gun control is watch the front sight and use both hands!