I have two 6.5X284's that I just finally finished for this shooting season. While they both shoot AWESOME they are so different in speed it's very strange. I have always been told that berger hybrids are a little faster than the VLD's because of the smaller bearing surface. so I exspected that to hold true and it didn't in this case. here are the details:
6.5X284 custom action, standard neck - 29" Krieger barrel and it's shooting the 140 hybrids @ 2980fps.
6.5X284 Savage action, .290 neck - 29" Hart barrel and it's shooting the 140 Hunting VLD's @ 3085fps.
Same powder and primers, but the custom action is shooting .4 grains more than the savage. I just find it amazing that they can be so different.
both the same amount of grooves. The bench gun does have a little more freebore and the bullets are set out a little further than the savage but I didn't think that would make 100 feet difference since it has .4 grains more. I am happy with both just find the difference in speeds odd.
Shoot 'em both a few hundred rounds; I suspect it'll even out as the throats wear a bit. I had a 7rum that was a bit slow to start with. Within a couple hundred rounds it was right where it should have been.
I have 150 rounds on the Custom action gun
I have 98 rounds on the Savage
I know they might speed up a little and thats fine I am very happy with the speed of both just don't know why the savage is so much faster. not a bad problem to have since they are both shooting bug hole size groups.