Without having such a magazine, there are basically two issues I would think of.

-) pressure plate (thickness of film channel/tension)

-) frame spacing / frame counter (measured by advance/ by spool rotation)


One could check the residual way the spring loading of the pressure plate yields without any film and with bare and paper-backed film and compare these.

But more telling would be just to run a film through and look for scratching on the base- and emulsion side. Best even compared to a type 220 film tun through. A uniform exposure for neutral density might reveal any pressure induced. The same time c

The same goes for the advance. One might not even need to process a film for this but mark the frames from within the image aperture. The same time checking what the frame counter indicates.