Curious, why does everyone think they need anything faster then a 8tw to run the heavy for caliber 130's?
I used a Bartlein 8tw finished at 22 on my 25 SAUM to shoot the 134's and it stacks them up about as good as anything I've ever owned. I bought a Proof CF .257 barrel awhile back to make a 25CM and it's a 7.5tw but that's only because it's what they had available.
An 8tw seems to be getting it done fine and all the twist calculators I've run it through put the 134's at a SG of 1.50+ For a little extra security I guess a 7.5tw would be fine but I don't understand why anyone would need anything faster unless you plan to shoot some custom lathe turned bullets that are realllllly long.