A 447 A.C. won't climb at 30 mph. 40 or above. I weigh the same as you and put hundreds of hours on mine. It is not a rocket, but it will climb.
Make certain you have the proper pitch blocks on the Ultra. I believe the A.C. used 13-degree blocks, but others will know better.
The Ultra is not an ideal prop because (1) the leading edges are sharp when they should be rounded (2) the blades are untwisted. As other posters have noted, there are better-performing props.
25 feet is an awful lot of rotor for such a light gyro. Dennis Fetters tried 25-footers on the A.C. 447 but settled on 23's. A rotor that is is too lightly loaded will spin too slowly, which creates a cluster of problems.
Two LIFE and DEATH safety tips:
(1) get some good gyro training. If you're trying to make a 447 climb at 30, your training was not thorough enough!
(2) make certain that you have a horizontal stabilizer on your gyro. The factory job works nicely. Without a stab, an Air Command lowrider is a proven widowmaker! Its prop thrustline is 5-6" above its CG, making it extremely prone to power pushover (PPO). And, anyway, it handles far better with the stab. Night and day, in fact.