Post by deadeye on Feb 19, 2016 10:22:37 GMT -5
2/16/16- played hookie from work to go play long on farm fields-last day possible since a thaw is upon us.
1st up were a couple of rifles getting ready for elk hunt this fall to get drops & make sure they were flying correctly..308 & 300rum//2hot groups today due to all I had to get in.
500yd-.308 1"
wind overcompensated on purpose to make sure I was on the board,shot both @ 650yds with satisfaction,stopped @ a few distance's to check wind in relation to cover & no cover areas.got my drops logged for future work-rifles good.
.458 brux HIS-1/20 twist
prior session a week ago smooth form bullets resulted in keyholing @ 623yds with pittman 325(kp) & parker 327's,shot the 344 bomb also but brainfarted & launched @ wrong target.
load that day-kp & 327=73.0gns h4198 with wool wad both bullets hitting approx. 4"high @ 200yds//344bomb 90gns 3031 approx. 3.5"high @ 200yds//310apb zero @ 200yds
so today I would leave all bullets sized as prior & no adjustments on my burris xtrII ffp 3x15,i would use a 2.5mil hold on all @ 500yds.....5.1mil hold on all at 650yds hopefully to check for stability & if stability exist get some drops for all 3 bullets with their respective loads. fwiw
**only change was replacing wool wad with the walters .060 veggie wad with no work from the 200yd bench - a gamble**
the rest on top of truck cab with plywood was somewhat stable but all I had at this time to pull this off,had to be very careful as to not manipulate the rifle as I was testing practice holds if I made any mistakes vertical was showing through the scope view. not the best condition but what I had to deal with today.
the plan was to launch 2shot groups @ 500yds,check & go to 650yds-driving to the target each & every time after a 2shot group for each bullet.
wind was approx. 5-6mph at gunrest from 4"30 for about 100yds, approx. 3-4mph 3"00 for approx. 350yds & the last 200yds @ target wind was wrapping around some cover & hitting from 1"30 @ 5mph.
1st up 325 pittmans @ 500yds
1.25"@ 500yds-lucky I know.> then shot a 2shot @ 650yds-13.5" but no keyholing
the farm field was showing signs of it would get too soft soon ,so not much time so I elected to finish the rest @ 650yds since I was on the board comfortably.
650yds board results with 5.1mil hold
pittman 325-13.5" approx. 5" below poa ............ sighted @ 4.0"high@200yds
parker 327-11.5"(1 loaded loose)5" above poa.........sighted @ 4.0"high@200yds
344bomb- 2@ 6.25" ,3@15.25"/ 11" above poa for 2high shots,lower shot could have very well been a difference of bore changing from the h4198 loads,thats why I shot 3....sighted 3.0"high@200yds
310apb- 7.5" vertical (with 1 loading loose) 17"high above poa........zero@200yds.
.308-5.5"
with testing in the past @ 650yds after this test I have come to the conclusion that in order for a smooth sized bullet to do well at these distance's with this bullet jacket thickness it probably will have to go down the bore with approx. 40lbs or more of loading resistance-definitely not suggesting a hammer down.
wad-in this case with all bullets it made a difference(no keyholing on all) 310 apb was full formed no wad 74.0 gns h4198
I do not believe a duplex will solve it either since the photo below was a 325be load was n110 boosted & keyholed in 2011 with a pacnor 1/22 twist.
I was able to achieve later great results with this barrel out to near 800yds with more loading pressure-approx. 40lbs.
I can see the reason full form dies were invented.
not a great group day @ 650 but I think I learned a few things today
enough "yawing" for now 
