Material for shooter wheel?

[Benjins]

Hey all,

So our team has been trying the two-wheeled linear shooter approach. Recently, we tried using 8" and 6" pneumatic wheels. The 8" shot the frisbees about 50', but the 6" one only shot them 5'. The 6" wheels weren't just smaller, they also seemed to be made of a different rubber. Since the smaller wheels would help fitting it on the chassis, we were wondering if any teams have used 6" wheels on a linear shooter, and if so if material seemed to matter.

Thanks for any info provided.