After all you have tried why not settle on the bullet you want to shoot and load up fifty rounds with a proper load you know that works and seat all the bullets 5-10 thou out of full jam. Then go to the range with your wind flags and an arbor press and start shooting two shot groups.Ok, Aint dead yet..lmfao..I will try to tell you the story so bare with me here..
I used the go gages to set the barrel as I have in the past..This is a 26 inch
bull barrel,7 twist,stainless..And with the wylde chamber..The barrel is floated
action screws are tight. Mounts is tight..
The box test was done on my sons rifle at 100 yards..It seems to have performed
very well..I have tried from 62 to 90 grain bullets...
Now at 100 yards it will do 1/4 inch 3 shots...At 300 which is where I need it
it will group maybe 4 to 8 inch..Not good...Checked the crown and the twist..
When I clean it,I GET NO copper at all...I think I am thru messing with it and
will get a Shilen...I had a McGowin befor which shot excellent..But shit happens.
I appreciate all your replies...
The wylde , was designed by Bill Wylde to allow the semi autos shoot both 556 and 223 safely with accuracy improvements in semi autos .Wylde was originally developed as a match chamber for .223, not to shoot both 5.56 and .223. That was just a happy coincidence. It is a perfectly fine chamber for a bolt gun.