I don't know what all this rubbish about the danger of emptying a blind mag is. I just point in a safe direction, strip the round out of the mag with the bolt and draw the bolt back. The round is never chambered and the bolt certainly never closed. This is just as quick as dropping a mag and stripping the rounds out by hand and replacing the mag in the rifle so it doesn't get lost.
I've never stalked in bush before but I gather that shorter rifles are easier to manoeuvre. Fatter bullets generally perform better in shorter barrels than narrower bullets and suppress better. Also when you have a short barrel then there isn't really the need to go to a big capacity case. From this the natural conclusion would be the mighty 308, but pretty much anything will do.
Disclaimer: I'm a relatively new shooter and know sod all and have even less experience.
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