Vortex scope issue

[AleksanderSuave]

Running a vortex razor gen 3. It’s been to vortex once for a turret “repair” (turrets would lock while dialing) and parallax knob adjustment..

Got the rifle out (badrock southfork) to my first mid range distances over the weekend, previously only went to 200 yards.
Staying consistent with the same ammo (federal gold medal sierra match kings).

Started the day about 8” low at 100. Rezero’d, went to shooting and the ballistics calculator (tried a few) did not line up at all with the scope.

At 300 yards approx, BC showed 14.5 moa up, but the scope was way over. About 7.25 up got me there.
After about half hour or so, spoke with the guy running the event and asked for help. I ended up rezoroing again..but the BC still didn’t match up to scope.

for example:
200 yards: had it set to 1 moa up
290: 2 moa up
530: 7 moa up
588: 10.25 up

Also, parallax knob was really odd. Had to be on the 150 mark to see well around 600 yards.

After all that took it back to the 100 yard range and had to rezero again, it was shooting high. Did a quick box test..seemed ok.
Ammo was federal gold medal sierra match kings.

Checked scope rings, action screws, muzzle device, nothing loose.

Vortex said they think it was simply the wrong muzzle velocity in the BC, but offered to test the scope for me. Any ideas before I send it back a second time?

 

[swd]

What cartridge and bullet? 14.5 MOA is a lot of elevation if it’s a center fire rifle. That’s 600 yards+ for my rifles.

 

[AleksanderSuave]

6.5 creedmoor, it was federal gold medal sierra match kings 140 grain

 

[Eagle Six]

Your scope may be bad and need service, but first I would check your ballistics calculator. It's just a calculator, garbage in, garbage out. It's seems to be giving you garbage as a solution.

 

[LiveFire]

Have you ran your ammo through a chronograph?

 

[Eagle Six]

for example:
200 yards: had it set to 1 moa up
290: 2 moa up
530: 7 moa up
588: 10.25 up

These do not seem to make sense. The 200 is good, 290 isn't enough, 530 isn't enough, 588 is about right.

Of course that is with my AB calculator comparing various loads. I would start going over the input you made in your calculator. And then confirm you feel good about you marksmanship and the distance to target.

 

[STOMP442]

Calculator issue for sure. Sounds like its giving you clicks instead of MOA. 14 clicks I can believe at 300 yards. Moa should only be about 3 to 3.5 for a 100 yard zero on a Creed. 14 clicks is exactly 3.5 MOA if you were to dial it up counting clicks.

 

[swd]

6.5 creedmoor, it was federal gold medal sierra match kings 140 grain

Here’s calcs for a 140SMK at 2650, should be very conservative speed wise. How did your actual come ups compare.

 

[AleksanderSuave]

just to verify, I ran the BC myself, had a buddy run his own, and the RSO running the long range shoot at our club ran his own calculations in strelok pro.

Its been a while since I ran a chrono on this, so we used the ammo box velocity to try to get close.

In all 3 instances, none of the values were even remotely close to accurate.

For all of the above distances, the RSO used an LRF to confirm distance as well.

 

[AleksanderSuave]

Here’s calcs for a 140SMK at 2650, should be very conservative speed wise. How did your actual come ups compare.

my table in chairgun elite BC is pretty similar to these values.

 

[fkimble@charter.net]

Are your clicks each up from 100 zero are they additive from the previous distance?

Frank

 

[Jarhead6870]

What ballistic solver are you using? Are you using a G1 or G7 drag model and what is your BC number entered?

 

[LiveFire]

I went to federals website and punched their info into strelok pro and got this chart. The numbers look different than what you were getting from your calculator.

 

[Seagull]

What rail and rings do you have . If you dnt have a 20moa rail that mite be why your elevations are strange .

 

[rijndael]

What rail and rings do you have . If you dnt have a 20moa rail that mite be why your elevations are strange .

As long as he's zero'd at say 100, and he puts that in his calculator, rail and rings are irrelevant.

 

[AleksanderSuave]

What rail and rings do you have . If you dnt have a 20moa rail that mite be why your elevations are strange .

20 moa rail (standard from badrock) and I believe its the 1.1" tall vortex PMR rings

 

[AleksanderSuave]

Are your clicks each up from 100 zero are they additive from the previous distance?

Frank

from the 100 yard zero

 

[jepp2]

Also, parallax knob was really odd. Had to be on the 150 mark to see well around 600 yards.

Maybe your experience has been different, but I only use the numbers printed on the parallax dial to know which way to turn it. I've never had a scope (many brands and models) that you could get the parallax actual to match the number on the knob.

 

[fkimble@charter.net]

I'm with Jepp2, the parrallax numbers are never "right". Loved the old Weaver "T" series. The parrallax numbers were like a micrometer. You spent the time testing each yardage and writing it down. Them you could dial it in perfectly at any yardage. I put tape on my knob or tube depending on how its set up and as I test the different yeadlines, I mark the tape. Once and done.

Frank

 

[AleksanderSuave]

Maybe your experience has been different, but I only use the numbers printed on the parallax dial to know which way to turn it. I've never had a scope (many brands and models) that you could get the parallax actual to match the number on the knob.

Yes, never been dead on but my other scopes have been somewhat close.

When I spoke with vortex rep he said specifically that having to be on the 150 yard parallax mark, when I was shooting to 600, was very odd, and possibly a sign of an issue.

Knowing that they worked on the parallax, windage, and elevation turrets, Im inclined to believe that any (or all 3) may still have issues..