6.5-06 Ackley Improved
I've been loading this round for about 3 years, and found significantly improved accuracy & velocities when I switched to Alliant Reloader powders, specifically RL19 and even better, RL22. (I wonder if RL 25 is toooo sloooow for this 30-06-sized cartridge?). But.... I note that Alliant's reloading info lists recipies that give very slow "V" in my rifle, which is: Rem 700 custom, Douglas 28" match stainless hand-lapped bbl, 1 in 9.5" twist, semi-tight custom chamber. My reloads when I was living in California (only mentioned because the average temp when shooting in SoCal was > 80˚ and some velocities were "improved" by cartridge temp....) were pretty hot.
I ended up with RL22 loads for 140gr bullets in the 59 to 61gr range, whaaay higher than Alliant even lists for the 264 Win Mag. And I saw velocities in the 3250 range! Wow! Some of those loads left primer pockets either "vacant" or leaking smoke when I opened the action. Now that I'm older and wiser (and still alive...) I've dialed 'em back to 57 - 59gr, and see velocities in the 3050 range, still effective on elk, deer, moose, caribou, etc. But again, Alliant would have me using max loads of about 55 - 56, which renders velocities in the 2600 2700 fps range. What gives? Anyone else have any experience with similar cartridges? Note on PO Ackley's comments on the 6.5-06 Improved: bull tweety! Too bad he didn't have today's powders but it's still hard to fathom his logic that the 6.5-06 Imp. showed no improvements over the non-Imp, given that he saw velocity increases with the -06 based imp cartridges that bracket the 6.5 The 25-06 AI, 280 AI, 270 AI all worked better than their parents. Ahh well; science moves on!