Dober - Re: 130 ABs, I ran 44/IMR4350, first 2 in same hole, and the 3-shot groups went 1.25, at 200 yds. This was Fed 7/08 and 308 brass respectively.
RP brass did about the same size group, but triangle shaped. At 100 yds, RP did .5-.6 out the box in a custom heavy bbl, while Noz shot in the 4s and under when I did my part.
Not sure what load you ran in your 130 tests.
The 129s shot great in my 9 twist custom 6.5-308 23" long ago.
A 129 has a bearing surface similar to many 120s and has speeds close - in the 2800s often.
No doubt your 120BT/3K load is a deadly one. In the past I ran IMR4350 and 414 for best results. 414 metered great, but not used enough to know if temp sensitive.
H4350 is what I use now, though RL series may get tried and a few more. Varget can do well w/light bullets, as 4320 if you have any to burn up.
My 9" custom did not like OVER 129s, but a Sako 75 also w/9" did fine w/Amax 140s, Berger 139/140, and 142 SMK HP, all under 1", but that gun again - put 2 in the SAME HOLE at 200 yds twice back to back out of 3 shot groups, using a 20x scope.
Good look, and good hunting.
