Doesn`t make sense ???

[Double Naught Spy]

I`m running Lapua cases.
Lapua Scenar 123 HPBT.
CCI #200 Primers.
28.5 GR. Varget.

Wilson 22" Barrel.
Cryptics Coating BCG.

Deviation is under 10
Some of the FPS are identical !

The problem is at 100 yards the spread is more that 2" ???
What is going on here ???

Please help I`m stumped ???

Simply put, velocity and standard deviation are not the the only components of precision. The SD and velocity are just telling you that your loading and burn rates are producing consistent results, but that may not jive with your particular barrel and harmonics, assuming that you didn't introduce in problems into the equation as the shooter. You need to find the correct combination that works with your barrel, not just the combination that produces good SD. You may need to be consistent at a different velocity.

I just noticed, the brake had come loose !!!

Or your muzzle brake has come loose and messed up things at the end of the barrel.

So did tightening it down resolve the issue?