Bore up sets a waste of time ?
 

I was thinking about installing a systema bore up set for better accuracy and velocity but have read that they will only work properly with at the very least a m 130 spring. I think its safe to say that the FPS would be much to high. Has anyone had success with a bore up set and a ms 120 spring or is it just a waste of time ? Thanks

The spring doesn't need to be as high as an M130.

Minimum is a Systema M120 or equivalent, so a Prometheus MS120SP is sufficient. That is information that I have acquired directly from Systema.

I've effectively run a bore up set in an Armalite with 6.03mm tightbore 590mm length inner barrel and Systema M120S spring. That setup was shooting ~425fps.

Excellent !! Thanks so much