plus the Carc used a removeable magazine ' clip' that dropped lower and lower until it fell out, when empty. you could not add carts to it if it were a few low, and you could not pull it out, unless you emptied the thing by racking the bolt.
plus if you did not have the rounds in the clip just right, you would get a jamm o matic; this reason alone makes many peeps feel there is no way in Hell's Bathroom, he coulda pulled off what he supposedly did...