I have also chrono'd the Hornady Factory 120gr GMX at ~3050 and the 123gr Scenars at 3060, using RE-17 (23" barrel).

Depending on your choice of 120gr Mono, it should be possible to achieve >3,000 ft/sec without excessive pressure, so long as you use either fairly fast powders, or a barrel >24".
If you do, it's a great flat-shooting load and should kill anything within a quarter of a mile!