The Kel-Tec CMR-30 uses the same magazines as Kel-Tec’s PMR-30 pistol, and holds 30-rounds of .22 WMR ammunition.
Like any rimfire firearm, you will need to experiment to see exactly what kind of ammunition that your individual firearm likes and what it doesn’t. In one of the videos below the carbine does not like Winchester ammunition. The host states that his rifle likes CCI brand ammunition.
If you don’t have the patience for a detailed explanation, then you will still be well served by the information above. If you want to know more, keep reading.
Nutnfancy’s won’t allow his YouTube videos to be embedded, but this one is important enough that I’m adding a link. You can watch the whole video if you choose, however the following link will take you to the point where he presents a critique of what is the weak point in reliability with the CMR-30: Nutnfancy’s KelTec CMR-30: What Coulda’ Been Ain’t