They aren't as effective. Still, its funnier tickling people to death with the 303s
I shot down A20s with the mosquito's 4x0.303s. At least in one case where we were 1v1 and the A20 was fresh, it took a little over 2000 rounds (out of my 3200) to bring it down. I am not a very good shot, but given the short distances and the size of the A20, I'll assume I was hitting at least 10%, so that means at least 200 "ping-ping-ping" sounds in the other guy's head phones...
Finally his tail came off and he floated down to the sea, but if he would have exploded mid-air, he'd still be hearing "ping-ping-ping" for like 10 seconds in the tower. 12x0.303 will do the job in less than 1/3 of the time because in addition to throwing 3 times as many slugs per sec, you are more likely to concentrate damage on one critical component of the target. The other guy will probably still be hearing pings for half a minute in the tower...
I know of at least one kill by a real 12x0.303 typhoon. However, that armament was quickly phased out.
