Another Long Range shooter, a good friend of mine has a 25/284. I shoot with him a lot and his 25/284 is almost a duplicate of my 25/06 as far as loads and velocities are, they both have 26" to 27" Hart barrels (10" twist). Both rifles shoot 108 VLD JLKs real good. I shot a 5-shot 7" group with mine @ 1022 yds, with the 108 VLDs, with 54 grH4831, velocity 3150 fps, from a 200 yd zero bullet only dropped 248", which is very flat for a 25 cal. JLK said he never figured out the BC for this bullet but it was around .500, I believe it might be a little higher. I think you will have difficulty reaching 3500 fps with 100 gr bullets, but please let me know how you make out.