if these are the #'s that the Nitro Gas ram generates as published then my; your 34 are safe
Crosman Premiers 14.3-grains averaged 712 f.p.s.
spread was from 695 to 727, for a total of 32 f.p.s.
average velocity generates a muzzle energy of 16.1 f/p.
RWS Superdomes 14.5 grains averaged 694 f.p.s.
spread was from 680 to 709, for a total of 29 f.p.s.
average velocity generates a muzzle energy of 15.51 f/p.
RWS Hobbys 11.9 grains averaged 771 f.p.s.
spread was from 761 to 781 for a spread of 20 fps
average velocity generates a muzzle energy of 15.71 f/p
Air Arms domes 15.9 grains averaged 673 f.p.s.
spread was from 664 to 679 for a total of just 15 f.p.s.
average velocity generates a muzzle energy of 15.99 f/p
I have the M34 and M94 shooting 720-730 FPS with 14.3 with CP 14.3 grains, tuned of course