The most likely cause is extra resistance during rewind or from the reusable cartridge, not normal frame advance. Since your frame spacing and transport appear normal, the film is probably feeding correctly while shooting. Torn sprocket holes usually happen when the film is being pulled while something binds—such as a take-up spool jamming during rewind, the film catching on a sprocket, or a reusable cartridge creating too much drag.

With bulk-loaded film, there’s also no factory-set roll end, so if you keep winding after the roll is effectively finished, you can stress the sprocket holes. Reusable cartridges can also be finicky if they’re closed too tightly or pinch the film.

What to try:

• Test with scrap film in daylight to feel for drag.
• Compare with a factory-loaded cartridge in the same camera.
• Check reusable cartridges for pinching or excessive friction.
• Be gentle when you reach the end of the roll and during rewind.
• If needed, inspect the camera during a test run (with sacrificial film) to see where it catches.

So the issue is most likely cartridge/rewind friction rather than the film itself damaging during normal advance.