Notice the single stack magazine from the link.
These straight tapered rounds don't feed worth a hoot, straight alignment with the chamber is critical, and, as it turns out for the 450 Bushmaster, if there are more than five rounds in the magazine the rounds will jumble and jam. Maybe that is why I am not seeing a ten round 6.5 PRC magazine in the picture.
Times have changed from the era in shooting competition when magazine feed was important. When I shot NRA Across the Course, you had two stages of rapid fire, with a reload. If you gun jammed your score suffered. The shooting game has gone to prone, single shot only, and no one feeds from the magazine anymore. Nor do some shooters want an ejector, they stick their finger in the loading port and remove the fired cartridge with their finger.
As I understand, Smallbore prone went single shot because competitors were upset when the guys who had five round (or more) magazines went full auto before the wind changed! A procedure of taking sighters until shots stayed in the X ring and the wind seemed stable, and then inserting a ten round magazine twice and and getting all shots off as fast as possible, would seem to be a match winning practice. In fact, I have noticed some unhappiness in the F class world, on electronic targets, where shooters blaze off their 20 rounds for record in under two minutes. Getting those rounds downrange before the wind changes is very important.
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