I have some Remington Core-Lokt .30-40 krag brass I fired recently. I have an old box of Western 180gr .30-40 krag that I would like to fire and reload. When I look at the two cases I notice difference in shapes. The old Western Super X round has a longer Neck. I resized the remington cases but the shoulders still do not match. Is it normal that there be different shaped casings for the same round? Is there a problem with shooting the older Western rounds even though the case is different?