By RIO I assume you mean the Royal Buck? It worked just fine but then I only fired one round at a time. One round of one brand in the chamber and another brand in the magazine for those targets where I shot a side by side pattern.
I bought 5 round boxes for testing but I see where Estate, Royal Buck and maybe one or two others have 25 round boxes of 00 which work out to be a lot cheaper for 5 rounds than the small boxes. There's better performing ammo out there but again, this is a shotgun at close range. If Estate or Royal Buck was all I could get my hands on I sure wouldn't feel helpless.
Gunnery, gunnery, gunnery.
Hit the target, all else is twaddle!
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