Strange Things goin' on here...
All 3 groups (5 rnds Total per.) start with bug-holes then 5th shot goes left 1/2"...and Next 5 rounds are a .7" -.8" group...Each Time.
I can "call" 1 of those that wrecked the 0.148" group, (but not that far off) but I know sight-picture and trigger-control, etc. were as good as the pictured groups when things went to .7"-.8"
These loads were Hand Trickled to a Digital Hornady scale and then Beam-Scale confirmed to +- 0.05 grains before charging. Brass is all FL sized, trimmed, and seating done with Forster BR die. Essentially Zero Run-Out with this fantastic die. Bullets were 69 SMK's seated to 2.30 - 2.305 OAL on the smallest and 2.345 on the other two groups. Ogive-length was checked for consist. with caliper tool. Powder is VV-N135 and primers Rem. BR-SR. Short of turning the necks it doesn't get much more accuracy-anal that that.
Bore was not scrubbed recently as I shoot about 200 before "Real" cleaning. Usually 2-3 Hopes patches and then dry bore before case. Prob. about 150 rnds. into that cycle. Gun is a Bone-Stock, Thumb-Hole, Savage (BTCSS) .223 with 36x Fixed "T36". I can see very precisely on the paper at 100 yds. Everything is Tight as it should be.
I just have a hard time swallowing my hold and breathing-trigger work going to pot almost "Mechanically Cyclical" like this. So many of the shots in the .7-.8 groups (another 30 rnds.) both before & after the 3 groups above "felt" just as good as the first 4 shots in the 0.148...?
I am thinking that glass-bedding and aluminum pillars would do away with this strange behavior?
What about Heat of barrel? I never let it get too hot to put a hand on but it will get pretty warm below that level.
Lastly, temp 75, wind 5-8 mph, 100 yds between 20 Ft. berms all the way down with lots of trees on top...Essentially zero wind effect on that light a day at only 100, I think.
OK, Time for the Gun-Doctors to take over here and let me know if you think I just SUCK, or if there may be something to this "Gun-Change Rhythm" that a good Epoxy & Pillar job might cure.
Standing-By and Eager as the Devil to Hear ALL..
Steve D.
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