When I carry in the field I always use a Wilderness Safepacker (link below). Depending on the size of the firearm these can get a little bulky, but the concept is sound. With the velcro system you can attach them to a lot of things, plus your firearm and an extra magazine are always covered and fully protected from brush. it only takes a couple of seconds to click the buckle and access your weapon too. They're not cheap, but you buy it once and you're good - made in the USA! I have 5 and my wife has 1, so 6 in the family (so far).
https://www.thewilderness.com/safepacker-concealment-holster/
