Has anyone found that their AR-15 POI shifts down when their gun warms up? I shoot about 1 shot per minute usually in 5 shot groups. I first noticed this when shoot at the 600 yard range and as the day went on I had to hold over more. I would think the gun warming up would increase the velocity but it appears the opposite is happening. A guy at the range suggested maybe my gas port opens up a little (its not adjustable) as it warms up. Any ideas why my POI is shifting down as the gun warms up?
Thanks,
Eric
Thanks,
Eric