Recent trend of hitting high

[msstate56]

(Started new thread)The last two matches- I’ve noticed a trend of hitting high. Myself- I’ve got a rifle and ammo combo with dope verified out to 1000 yards. This dope and ballistic calculator solution have been consistent under a variety of conditions. I’ve noticed other shooters and myself missing high quite a bit.
Conditions- 80-90F, ~70% RH, ~29.70 absolute. Wind gusty Left to Right 5-6, gust to 10. Mirage was present but very light. Like I said, I saw this enough from multiple shooters. I’m trying to figure out what we are missing? If it is light angle, target shadow, is there any way to combat that? Or do you just have to learn that certain targets on certain ranges do that?

 

[Deleted member 10043]

I seen wind vs terrain cause this for one thing.

 

[b6graham]

error in ranging target. mirage/light

 

[Deleted member 10043]

It is not uncommon. I don't bother zeroing back to 100 yards. I change the zero to match the dope as long as the distance isn't material. I have one rifle that ended being 180 yards. It hasn't changed over time. It doesn't have to be 100 yards.

 

[Erno86]

Higher temperatures makes the air less dense...so the bullet will go higher if you sighted in on a colder day.

Does the rifle have a left or right hand twist?

 

[LawnMM]

Follow through or terrain.

 

[msstate56]

Right hand 1/8

 

[msstate56]

I noticed it from multiple positions, prone with rear bag, off PRS barricade, etc.

One thing I noticed when cleaning my rifle last night was a significant buildup of carbon in the blast chamber of my TBAC U7. So much so that some of it scrapped off on the muzzle brake when I unthreaded the can. I clean the carbon off the TBAC brake every 100-150 rounds. Would this buildup inside the can be leading to increased muzzle velocity?

 

[Meety Peety]

How high are we talking and at what distances? Are we talking about a couple tenths at 800 or are you missing a 300 yard target by a mil? There are a lot of things that could be factors, without being there and/or knowing all of the details, I'd just be guessing. That being said, I am going to guess incorrect target distances. Who ranged them and are you missing high across the board or just on certain stages/certain targets? I see a lot of guys miss high at every match, they also miss low, left, and right too. I would ask the guy who cleaned it if he noticed any peculiarities and made an adjustment. This is assuming you have no issues with your zero, velocity, dope, scope tracking, breathing etc.

 

[Faronth]

Any chance your ammunition temp was up? 90 degree day, was it in the sun long enough to heat up above ambient temp? I have been at a range and not notice the sun creeping up and have left ammo in the direct sun accidentally, (I live in Arizona). Were rounds loaded into a hot bore and left for a bit before shooting?

 

[msstate56]

No rounds were loaded until start of the stage. All ammo was kept in my pack, in the shade.

Towards the end of the match, I was hitting high across the board. That included 4 different stages shot from multiple positions. Ranges were given on the match sheets, and I don’t think anyone argued they were wrong. Hits were .2-.3 high. Enough that I was missing over the shoulder of a reduced IPSC at 500-600. Target ranges were 200-647 yards. It got to where I had to hold at the bottom of the IPSC to hit center. Some shooters didn’t seem to have an issue, and some others like myself were missing high. There was a lake off to the left, and most of the “high” stages were up the hill off the lake. I guess it’s possible that the wind coming up the hill could have pushed bullets high. But that still doesn’t explain why someone who shot in the same wind didn’t hit high, then I did right after.

 

[b6graham]

significant DA change

 

[Fig]

The gravitational pull of the earth has lessened due to climate change... It's making everyone hit high...
This thread is an arrow into the sky.

I will say I've seen wind and terrain do crazy things with a bullet. This is especially true out West in the wide open spaces. I've seen up and down drafts over a hill move bullets twenty feet at range. This to the point where you can hardly believe how much it's pushing them around. It doesn't seem possible, but there it is.
"Hold .4 high"...*DING*. There is likely nothing wrong with your dope.

This is why recoil mitigation, follow through, and accurately spotting your misses is so critical. Often you can't predict what terrain and wind are going to do way out there. The first one you send is sometimes an immediate form of dope (when the shot feels right). It's won or lost based on how you handle the misses rather than the ones that impact by the book.

That's part of what makes the guys who are good so good, and how they can consistently hit 90%+ of the targets. Yea, they're good shots, but they're also good at correcting their shots.

 

[msstate56]

That’s essentially what I ended up doing on the last 2 stages. I said I don’t know why it’s going high- but it is- so I just held low and it resulted in hits.

 

[Erno86]

Is the rifle barrel free floated?

Of course...any undue downward pressure on the forearm of a non-free floated barrel, will have a tendency for the P.O.I. to shift higher.

 

[Rancid Coolaid]

Were you shooting at an uphill target?

 

[bschneiderheinze]

I’ve been having this same problem .3 at 600 and 2-3 tenths under 600. I hit targets from 600-1000. I hit a 8” ground hog at 1000 but under 600 had problems. I was even missing at 300 yards. Went from a van seat where I missed four targets at 415 yards to prone and aiming under them and got all 4 hits. Just can’t get my dope to line up across the board. I guess all just take a couple tenths out under 600 at the next match.

 

[msstate56]

Barrel is free floated in a chassis, and no up or down hill to the targets (well not more than a degree or two). I’m beginning to think it has more to do with atmospherics in relation to the way my eye is seeing the targets, possibly in conjunction with mirage.

 

[Conrad]

Verify: zero, optic height, atmospherics—as in did you reference atmospherics as the day warmed up?

Consider wind via terrain.

After that, then yes, think about Snell’s law, it happens.

 

[wade2big]

I’ve been having this same problem .3 at 600 and 2-3 tenths under 600. I hit targets from 600-1000. I hit a 8” ground hog at 1000 but under 600 had problems. I was even missing at 300 yards. Went from a van seat where I missed four targets at 415 yards to prone and aiming under them and got all 4 hits. Just can’t get my dope to line up across the board. I guess all just take a couple tenths out under 600 at the next match.

You could just shoot a target and measure the correction with your reticle. Write down that number. Do this every 100 yards until you reach your max range. Those numbers you just wrote down are practical working numbers. The numbers written down match your rifle, ammo, and you. You do not need to match theoretical numbers that a ballistic app spits out. Remember that cell phones are relatively new. Shooting is not.

 

[bschneiderheinze]

You could just shoot a target and measure the correction with your reticle. Write down that number. Do this every 100 yards until you reach your max range. Those numbers you just wrote down are practical working numbers. The numbers written down match your rifle, ammo, and you. You do not need to match theoretical numbers that a ballistic app spits out. Remember that cell phones are relatively new. Shooting is not.

I plan on doing this but current my range is shut down due to flooding

 

[wade2big]

I plan on doing this but current my range is shut down due to flooding

That sucks. We dealt with it not long ago with ther Hurricanes and tropical storms that tore up the Texas Gulf Coast.

 

[Erno86]

Naturally...you'll have P.O.I. issues if your eye is not perfectly centered in the scope or peep sight.

The only other scenario that I can think of at the moment...is inconsistent cheek weld position.