Recently received my Tikka-custom 280 Ackley Improved from Kampfeld Customs (build specs/gunsmith review posted in Firearms section) and couldn't wait to get to the range for some load development. I'm heading to Idaho next weekend for a mule deer hunt so being in a time crunch I set aside a weekend and had high hopes that this would be a smooth ordeal. Boy, was I surprised..
I loaded 20 rounds at a cross referenced safe charge and a 12 shot ladder all at mag length, and headed to the range. This rifle has a new #3 Bartlein barrel, so I followed Frank Greens break in procedure. Shoot 1 shot, clean, repeat for 5 rounds. Shoot a group, clean. Repeat until there is little to no copper fouling. The 4 shot group is shots 7, 8, 9, 10. Clean, foul, 3 shot group is shots 13, 14, 15. WOW.
The ladder test was 12 shots loaded in .4gr increments. I decided I was going to follow @rfurman24 YouTube video of a modified OCW method to get things worked out as fast as possible. The ladder test Identified a nice velocity plateau around the 57.6-58.4gr range, so I ran home and loaded (4) each at 58.2, 58.4, 58.6.
As you can see there was a velocity jump on the 3rd shot at the 58.4gr test charge, I attribute that to the case chambering hard and not having a desired .002" shoulder bump (I had some issues with sizing, I'm assuming because this brass was once fired out of a Savage chamber, and I believe my new chamber is on the tight side), but that happened to be the best group. If you pluck that shot the ES is 4. To me, this substantiates the ideology of harmonic tuning and the fact that consistent POI can mitigate some velocity spread. All of the test groups had the same general POI, so I loaded 20 more of 58.4 and headed to the long range. Zeroed the rifle, and two shots downrange at 400, and 600 had the same outcome, little high. Adjusted the velocity and BC until it matched the deviation I measured and adjusted the calculator, confirmed at 600, and the next couple shots repeatedly landed on a sub MOA target at 980 yards. Time to head to IDAHO!!
Final Load Specs for 162gr ELD-M:
58.4gr H4831SC
Hornady brass (that will be replaced ASAP)
CBTO: 2.595" - functional mag length (estimating about .080" - .100" jump, didn't measure and don't care)
CCI 200 Large Rifle Primer
Additional notes: This is actually my wife's rifle, so the velocity isn't screaming because I didn't want it to translate into more recoil and during the build all I could stock up on were these Match bullets. I hope to obtain some 140 VLD's to test in this rifle eventually. Once this hunting season is over and the barrel speeds up I'll probably redo this test more extensively and involving seating, but for now I'm absolutely satisfied with the situation as a whole!
I loaded 20 rounds at a cross referenced safe charge and a 12 shot ladder all at mag length, and headed to the range. This rifle has a new #3 Bartlein barrel, so I followed Frank Greens break in procedure. Shoot 1 shot, clean, repeat for 5 rounds. Shoot a group, clean. Repeat until there is little to no copper fouling. The 4 shot group is shots 7, 8, 9, 10. Clean, foul, 3 shot group is shots 13, 14, 15. WOW.
The ladder test was 12 shots loaded in .4gr increments. I decided I was going to follow @rfurman24 YouTube video of a modified OCW method to get things worked out as fast as possible. The ladder test Identified a nice velocity plateau around the 57.6-58.4gr range, so I ran home and loaded (4) each at 58.2, 58.4, 58.6.
As you can see there was a velocity jump on the 3rd shot at the 58.4gr test charge, I attribute that to the case chambering hard and not having a desired .002" shoulder bump (I had some issues with sizing, I'm assuming because this brass was once fired out of a Savage chamber, and I believe my new chamber is on the tight side), but that happened to be the best group. If you pluck that shot the ES is 4. To me, this substantiates the ideology of harmonic tuning and the fact that consistent POI can mitigate some velocity spread. All of the test groups had the same general POI, so I loaded 20 more of 58.4 and headed to the long range. Zeroed the rifle, and two shots downrange at 400, and 600 had the same outcome, little high. Adjusted the velocity and BC until it matched the deviation I measured and adjusted the calculator, confirmed at 600, and the next couple shots repeatedly landed on a sub MOA target at 980 yards. Time to head to IDAHO!!
Final Load Specs for 162gr ELD-M:
58.4gr H4831SC
Hornady brass (that will be replaced ASAP)
CBTO: 2.595" - functional mag length (estimating about .080" - .100" jump, didn't measure and don't care)
CCI 200 Large Rifle Primer
Additional notes: This is actually my wife's rifle, so the velocity isn't screaming because I didn't want it to translate into more recoil and during the build all I could stock up on were these Match bullets. I hope to obtain some 140 VLD's to test in this rifle eventually. Once this hunting season is over and the barrel speeds up I'll probably redo this test more extensively and involving seating, but for now I'm absolutely satisfied with the situation as a whole!
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