I am not a hair splitter, when it comes what round is the best. I do not own a 6.5x55, nor the Creed. I do, however, own a Criterion-barreled .260 on a Remington short action. It is phenomenally accurate (for my eyes) with about anything that I put through it. I can load the bullets to 2.848, but cut it close on the magazine. I have backed that off to 2.840, to enhance field functionality.
I like the 129 Interlock and can push it to just over 3000 fps from my 24-inch barrel, with a max (as per Nosler data) load of Re 17, with 1/2 moa accuracy.
I have recently done a bit of testing with the 147 ELD-M and Re 26. I started with 48 grains, using a mag primer and the load shot very well with an average of 2922 fps. The es was not good and one shot was 2964 fps. There was a bit of ejector marking, so I stared to back down a bit.
47.5 grains using standard primers got me 2891 fps, with an es of under 12. Mag primers opened up the es a bit, and were actually a few fps slower! The primers were somewhat flat, but not bad, even though it was a fairly warm day.
I dropped back to 47 grains. With the mag primers, the pressure signs were non-existent. I only fired two shots over the chrono and they were 2826 and 2825, which was pleasing. The standard primers averaged 2819 fps, for three shots, but had a bit worse spread. Accuracy-as with all the loads-was good enough for me. This moderate load is a full 100 fps faster than a max load of Re19, which clocks 2724 in my rifle.
I am going to test some 140 Partitions next in the coming days.
As I stated, I am not really a hair splitter. I don't measure distance off the lands etc., and generally seat to just over what the book recommendation is, depending. I have seen nothing that the 55, nor the Creed will do any better or worse than the .260. The 55 has the long mag, which is a plus, but a .260 put in a long mag allows less powder crunch, too.
Between these three, it is nothing but personal choice, as to which you choose. Throating, twist, yada, yada, yada, are the choices to make, but as far as difference, I can see nothing that would be a game changer to me.
