You could blow a fork seal if put the wrong pressure into the fork.

If you set a regulator to 50psi then you will only put 50psi into the fork, it won't magically put a large volume of air at 300psi into the fork and blow the fork to pieces.

I've used a compressor with a tire inflator to put air into a fork and it has never looked like blowing up.





I do recommend getting a shock pump.