Asking for comments on Hornady Superformance ammo

[Garand Hunter]

I am finishing up the sporter job on my 1909/38 Peruvian Mauser 7mmX57 rifle and with the 29 inch barrel I am lookin at great performing ammo over 250 - 300 yards for antelopes in Wyoming. These critters like to stay outa range most of the time. I have two boxes of Superformance 139 gr ammo on the way for some reach out and touch them action this coming October. Any comments on this ammo or other brands for long shots over rolling terrain ? Last year I used my .243 Mossberg 1550 and my BAR 7mm Mag. One hit with the Bar and they don't even twitch after the hit. Thanks.

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