I’ll make this one short. Did some velocity testing last week on the 260 and today on the 6.5-284 over the magneto and got the following results. Temperature difference of about 20 degrees is the only variance (colder today).
42.3gr H4350 in a 24” 1:8 260 Rem with 140 ELDM = 2795 FPS 5-shot average
Round count about 200.
47.3gr H4350 in a 24” 1:8 6.5-284 with 136 Scenae-L = 2760 FPS 5-shot average
Round count about 60.
Why would 5gr more powder cause a slower velocity? Same primer in both calibers, same muzzle brake.
42.3gr H4350 in a 24” 1:8 260 Rem with 140 ELDM = 2795 FPS 5-shot average
Round count about 200.
47.3gr H4350 in a 24” 1:8 6.5-284 with 136 Scenae-L = 2760 FPS 5-shot average
Round count about 60.
Why would 5gr more powder cause a slower velocity? Same primer in both calibers, same muzzle brake.