Re: Best Ammo for my new GAP Non-typical .300 WSM?
Something to consider with the mail order and semi-custom reloading shops, what happens when you need to buy replacement ammunition on the road? It may not be an issue for for those that exclusively hunt locally but, the people who fly and loose ammo know what I'm talking about (How would you like to fly to Africa with a ~$10K double rifle only to shoot some 20 year old well worn bolt action that had ammo in camp after practicing and training for a year on a DR)?You don't mention where you live so, it's hard to know what local shops are around you. If someplace like Cabela's or BassPro are near you, check what they normally stock so you have some idea what sort of short notice replacement ammunition is available locally.
In terms of what specifically to buy, it depends on what you are hunting. In general, I would suggest finding something with good performance on things like deer and another for tough animals like Elk, Bear, etc.
A final thought, you might want to call GAP and see what they recommend.