It appears that I found a "sweet spot" in the loading of the 130gr Accubonds for my .260 Remington rifle on the Encore. The spot appears to be between 45.8 and 46.2 grains of Reloder 19. The attached target was shot @ 100yds from a bench, a single shot with each powder charge. My scope is a Leupold VariX III 2.5x8 set on 8.
Any observations will be most appreciated.
Hey Rol...this is looking pretty interesting.
From the image that you posted...the grouping that you've outlined in yellow looks real nice. If it were me, this is what I'd do to verify the results.
Go through your empty cases and weigh them out into groups. Try to get at least 10 cases (15 cases would be better, with the same number of firings) that are within 5 grains of each other
by weight. Then load up 5 rounds each at both the 45.8 gr charge and the 46.2 gr charge. I would also load a 3rd set of 5 shells using a 46.0 gr load...This will put a load in the middle of your range and a nice even 46.0 gr load so easy to remember. Most of the time this probably won't make a huge difference in shot groupings at 100 yards, but you never know. My .308 will go from 1/2 inch to 1/4 inch groups with a 3 tenths grain change. I've never seen that in any of my other guns, but I've run enough rounds through that .308 that its not a fluke, its just a charactoristic of that gun.
Try to go to the range on a day when the shooting conditions are as near ideal as possible. This will eliminate many variables. Shoot 3 shot groups of each of your loads. The 2 extra shells of each loading will be in case you feel that you pulled a shot or 2. If all the shots feel good, then make them 5 shot groups.
I would suggest shooting each of the groups from as solid a rest as possible. (
I use a Carlson Lead Sled...very solid...shooter issues are greatly eliminated with this rest.) Shoot each grouping on a seprate target...clearly lable each target as to shooting conditions. Date; Time of Day; Temperature; Wind Conditions are the main biggies...I also like to include Relative Humidity.
I would take my cleaning kit to the range and clean the gun thoroughly between each group. And allow maybe a further 10 minute break before shooting further groups...to let the barrel cool down as much as possible. (
Cold Bore Shot Data...know where that 1st shot of each group hit on the target in relation to the other shots in the group...I take a series of photos with my cell phone and save the images to a data file on that gun. Over time, I know exactly where that Cold Bore Shot will go. If you have a rifle that puts the cold bore right into the group with the rest of them, keep that gun forever.)
Take your time and enjoy and don't forget to post us your results.
Very Cool
