Well, I finally got some testing done with this new Encore barrel.
First off, there isn't much for data on this round, so I was going from experience with various AI's, and at first had some puzzling results.
I elected to start with 1 gr. over max using H4831 .260 Rem data and the 125 gr Nosler Partition for my main deer bullet. As this case has a capacity is 1/2 way between the .260 and 6.5-06 cases.
On my initial 49 gr load, the velocity was about 250 fps over what I had expected. The cases extracted ok, but on the 3rd round, there was a slight hint of stickiness on opening. I went ahead and fired the 49.5 gr load,,,and it was pushing it. I quit there and went pulled the rest of the load ramp. From there I backed off 2 full gr., and 47 gr. proved still to be above what my hopes had been. Accuracy wasn't too bad, but I'll have to admit, I'm not the worlds best shot and also I haven't had much trigger time in all winter, so i know I wasn't at my best on the bench.
I did shoot the 47.5 gr. load, but group had opened up some.
I think the 49 gr. is absolute max in this barrel (17" Pac-Nor 9" twist polygonal OTT chambered). The some what puzzling part of why the one round was ever so slightly sticky, is I checked that lot of bullets and found .0005" variation in diameters. And that is also why I'm getting more variation in velocity than I had hoped. I'm happy with the 47 gr load in general, I would like to see that velocity spread tighter, but that's likely due to bullet diameter issue. Then too, I would like to see a higher load density, than I'm getting with the H4831. Still I'm getting better velocity then I had hoped when I decided on building this barrel. I can only assume that between the tight OTT chamber and possibly a tight bore, that I'm in the .260/Swede realm of data, and getting the velocity I am.. I really from experience would have guessed it top out in the 52 gr. with this powder bullet combination.
I think I'll get some more trigger time in and play around the 46.8 - 47.2 charge weights and see if I can't tighten up the numbers some. Then change from 100 yd zero and set up for point blank range on a 4" target. Then too, I might pick some RL22 or VV 165 and play around some more.
Sorry, kinda hard to read that pic, right is 47 gr. H4831 2769 fps avg., 22fps spread, .472 group,,,left 47.5 gr. 2807 fps avg., 39 fps spread, .703 group
Dave
