Its a 308 pre-fit on a howa 1500 in a krg bravo chassis shot with a front rest and rear bag. Tried 175 & 168 matchkings and 150 hornadys , 3-5 moa is just what it shoots. This action has never shot great but this is by far the worst.
Interesting,
Is it possible, as I heard relating to 260 Rem that Saami Specs for a 3 degree leade
And caused erratic accuracy issues with our new VLD type bullets
( according to Mr Tooley here I believe it was)
And similarly, could it be possibile that your 308 chamber - does not have a 1.5 deg leade angle?
Causing the same problem.
Just a thought that maybe simply throating the lead to ensure you have a 1.5deg may help bunches.
(In other words, no telling what 308 Reamer someone else used ,,,
.......just to get get the product out the door)
I have gotten very good accuracy with 175 TMK's in a variety of 9&10 twist 308s
so your Standard 175 SMK should do similar.
3 MOA is frustrating
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Another thought here
I once (Once is enough) tried an MDT chassis
Now granted it was their light LSS chassis
Regardless
Upon taking my barreld action out of a bedded wood stock which printed 1/2"
And placing it into the MDT chassis
My groups immediately opened up to 2-3 inches at 100 yds
I was beside myself
Checking everything else of course
Not correlating the two together, but then had to think that is the only thing I changed
So I put it back into the wood stock and low and behold it went right back to pringing 1/2" or less.
Come to find out the chassis flexed so much at the forend (I hate 6061 chassis's) that was the problem
Is your fore end stiff enough for your barrel, weight?