I use the 6mm Dasher Alpha cases, exclusively, they have been good cases...primer pockets are on the tight slide, so go with Remington 7 1/2 primers as the cups have a slight bevel allowing normal seating. They have been taking pressure well cause I pushed them a bit, as most handloaders do...
The 6mm Dasher could double as a varmint rifle, as I shot the 55 gr, 58 gr, and 70 gr with good accuracy and velocities...over 4000 fps with the 2 lighter bullets, and over 3700 fps with the 70 bullets. The 6mm Dasher is very versatile...could check the ballistics between the two, 6mm and 22 dasher to help with your decision, on what is right for your needs.