Cause for down range groups opening up?

[Rick Richard]

I have a Rem 308 5R that will shoot a ragged hole at 100 yards and .4s at 200, but opens up considreable at 300 and beyond. The projectile is the 168 AMAX being pushed by 44 grains of 4064. Can somone help me understand what is happening and what I can do to resolve the issue?

Thanks in advance for all informative feedback.

 

[4bycamper]

Thinking this could be a scope issue.

What scope are you using? Can you readjust the parallax?

 

[Rick Richard]

It is an older Burris 4 x 14 I believe and you can't adjust for parallex. I was sort of thinking this may be the case, but wanted some expert opinions.

Thanks!

 

[FearNoWind]

but opens up considreable at 300 and beyond.

How much is "considerable"?

Check your parallax:
Go outside and sight on something about 100 yards away. Move your eye side to side while you keep the object you're sighting on in your field of view. Then repeat the test moving your eye up and down. If the object appears to move in relation to the cross hairs in the scope you have a parallax problem.