Confused with my dope today

[Dski48]

Today at the range I was running 168 Berger's in my 308 and took them out to 1000 yards. I was using sterlok pro for my ballistic data and also using the weather flow meter for my atmospheric inputs. There was a slight right to left breeze at anywhere from 2-7 mph roughly. My dope was spot on at 300, 400 and 1000 but at 600 it was roughly 2.5 moa low. My rifle was shooting sub moa at all the other distances why would my data randomly be off only at 600 yards

 

[Olen_4504]

Two likely scenarios that may or may not apply, but have been the reason I’ve experienced this:

1) target wasn’t actually at 600 yards
2) mistake when dialing

I wasted 15 rounds the other weekend trying to hit 720yds and realized I was dialed 4.1 instead of 4.6

Doh

 

[Dski48]

I don't think it was the first one as I was at the range and the target was marked 600 yards and my buddy hit it with 600 yard dope and dope called for 14.9 moa and I was on 15.25 for the first shot and I hit super low. I had to dial to 17.5 to get a hit

 

[seansmd]

I wouldn't trust range signs for distance or buddy's dope. My jeans are labeled 34 inch, I don't trust that either ?

 

[clcustom1911]

I always confirm target distance with my laser rangefinder. The "200" yard line at my local range is actually 209. With short action cartridges, that doesn't matter....

But 22LR..... Yeah..... That changes things A LOT. That extra 9 yards equates to 7 more inches of drop.

 

[Dski48]

I wouldn't trust range signs for distance or buddy's dope. My jeans are labeled 34 inch, I don't trust that either ?

My first time out there I took my range finder. The targets were within 3-5 yards of what they said. I wouldn't inside such a small difference in distance would cause that big of a error

 

[Subwrx300]

My first time out there I took my range finder. The targets were within 3-5 yards of what they said. I wouldn't inside such a small difference in distance would cause that big of a error

If yardage is known to be correct ( by you and multiple readings from laser plus other people's dope lines up correctly), AND you've checked torque on all scope mount screws and bolts, that leaves 2 answers:

1. You did something drastically different in your fundamentals/shooting technique
2. Your scope has tracking issue in that range.

On number 2, my buddy had issues similar to yours where at about every 6-8MOA on the turret, it simply wouldn't come up the correct amount. The erector was sticking in that range and would get unstuck and go to proper elevation after 8-9MOA dialed but he had a dead spot in turret. Sent it back and they confirmed it.

Easy to test: Run a tall target test at 100yds, dialing your 300, 400, 500, 600, 700 and 1000 corrections. Keep shooting at a dot on the bottom edge of to target and see if the group centers (say 3 shots each) measure the correct distance from your POA and dialed solution. If it doesn't, time to get your scope looked at.

Reply back if you need guidance on running test, but your cardboard should be at least 40" tall to ensure your on paper throughout test. Put the 100 zero dot at the very bottom and keep aiming at it while dialing up for each group.

 

[Subwrx300]

If yardage is known to be correct ( by you and multiple readings from laser plus other people's dope lines up correctly), AND you've checked torque on all scope mount screws and bolts, that leaves 2 answers:

1. You did something drastically different in your fundamentals/shooting technique
2. Your scope has tracking issue in that range.

On number 2, my buddy had issues similar to yours where at about every 6-8MOA on the turret, it simply wouldn't come up the correct amount. The erector was sticking in that range and would get unstuck and go to proper elevation after 8-9MOA dialed but he had a dead spot in turret. Sent it back and they confirmed it.

Easy to test: Run a tall target test at 100yds, dialing your 300, 400, 500, 600, 700 and 1000 corrections. Keep shooting at a dot on the bottom edge of to target and see if the group centers (say 3 shots each) measure the correct distance from your POA and dialed solution. If it doesn't, time to get your scope looked at.

Reply back if you need guidance on running test, but your cardboard should be at least 40" tall to ensure your on paper throughout test. Put the 100 zero dot at the very bottom and keep aiming at it while dialing up for each group.

@Dski48 Need to add: make sure your berm at 100 stops shots 40-50" higher than poi or you'll be sending rounds into the stratosphere and neighboring properties. Easy to forget when we are just shooting at 100yds...