I'm shooting 7-6.5prcw in 2 different barrels in my ATX. 180 hybrids and 168 vlds are stuffed way below neck/shoulder to fit in a mag. 180s at mag length limit powder. I single load 180s in one of the barrels and it absolutely hammers but I can't get those results mag-fed. The other barrel is a short carbon barrel shooting 168's at mag length and I'm not giving up too much, a little velocity and maybe some accuracy seating into the shoulder but its not the bullet I was hoping to shoot. Short answer is, short mags work, but you're NOT gonna mag feed and get the same results you could from a longer action. Single loaded 180's below.
Also, the AW mags won't hold WSM rounds reliably. They'll vomit all the remaining rounds out the top after extracting a round in my experience. Maybe you could work the feed lips but IDK. MDT WSM/PRC mags work excellent in my ATX.
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