I agree with SAHUNT and 500Nitro as to quick detachable mounts and a LOW POWER SCOPE.
Personaly I would never mount a scope on a 505 Gibbs. I don't have a scope on my Brno 602 in 458 Win. or 458 Lott as I feel they are up close and personal work. But this is my opinion and perference. I want to be able to get on target as fast as possible, and for me open sights accomplish this best.
-------------------- Mauser Rifle
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