MV true up

[Rugger7622]

Quick question on MV true up. I shot yesterday for the 1st time over 300 yards. I shot at 500 yards and 565.

Gun: Tikka T3X, 22 Creedmoor, 16.5” PVA 1/7 twist, 85.5 Bergers at 3,032 MV, SWFA 3-15 scope. Set up on a bench with bags

500 yards, dialed 2.4 and hit right around where it should
565 yards, dialed 2.9 and hit 6” high

Seems like large dial up for 65 yards, but this was the solution with the Hornady app and AP app.

Would you true up MV for the 565 or shoot it again to confirm?

 

[HandgunHTR]

What is the diameter of your cone of impact at 100? What I am getting at is that if your cone of impact is about 1.2" at 100 yards, that equates to 6" at 500 yards, which means that for any given shot, they could be 6" apart from one another.

One shot should not be used to make decisions. Shoot groups of preferably 10 or more to make those types of decisions.

Another thing to note, a 0.5 mil adjustment at 560 yards equates to a 10" point of impact shift.

 

[Rugger7622]

With a 10 shot group at 100 yards, the Bergers are a bit under an inch. I normally would shoot 10 shot groups but at 500 yards I was just seeing what it would do to get on paper. I was surprised the solution in the apps had me come up that much for 65 more yards and then surprised I was 6” higher than the solution.

 

[Rugger7622]

Sorry, the 1st picture is from my 6.5 saum, shooting 156 Bergers. Here is the 500 yard picture of the 88.5 bergers.

 

[mxgsfmdpx]

Not a ton of experience with the Bergers these days, but something seems off here. Is it consistently hitting 6” high or just data on the one shot?

You aren’t shooting far enough to start dicking with trueing here in my experience. A quick pull into the Revic app using G7 shows these numbers…







If you are using known/proven BC for a good bullet, and using using a good/known chrono like the Garmin with consistent average MVs over 20 shot strings, and are still having an actual proven error in the ballistics data at 500-600 yards, you almost always have an issue somewhere else in the system.

Chasing and adjusting MV and BC at ranges below 600 like you are shooting is just gonna cause even more issues. Unless there is some “known” data issue with the specific bullet you are using that I am not aware of.

 

[Rugger7622]

I totally agree. The solution in the calculators were on at 300 and 500, but the solution provided for 565 was off by 6" high. Both calculators had me come up to 2.9mils vs. 2.4 for 500. It seems weird to me, but I've never shot this distance before.

 

[Rugger7622]

Also, I've shot around 50 of these 85.5's over a Garmin to get the average MV of this load. Probably best to got shoot the 300, 500 and 565 again to see if I did something wrong. The calculator was dead on my my saum. I also checked the dial up when I got back and it was still on 2.9mils, which was the 565 yard distance and what I shot last.

 

[Lawnboi]

I would not true mv if you have it confirmed with a chrono at that range with that bullet. You’re likely only building an error into your solver.

 

[Rugger7622]

I agree, I'll shoot it again to see if I get the same results. Just seems strange that the solver is on at 500 and would that far off 65 yards further.
Could have been something I did, but I cannot figure out what it was.

 

[Lawnboi]

I agree, I'll shoot it again to see if I get the same results. Just seems strange that the solver is on at 500 and would that far off 65 yards further.
Could have been something I did, but I cannot figure out what it was.

Most of the time when I see guys truing at that close of range I think cone of fire variables, or weapon system problems are causing the most error. It’s also easy to true some environmental factors in that rage into your solver. None of the above make for a solid system.

 

[Rugger7622]

Thank you. Not sure how it fell apart height wise in 65 yards, but I’ll shoot it again to see if it repeats

 

[mxgsfmdpx]

Thank you. Not sure how it fell apart height wise in 65 yards, but I’ll shoot it again to see if it repeats

For fun, before you do that. Reconfirm your 100 yard zero with 10 shots and chrono it while you’re at it

 

[Rugger7622]

I sure will, I shot a 10 shot group the week before and it was on and a .85”ish group. If it was off, wouldn’t the 400 and 500 yard poi’s have been off as well?

 

[Rugger7622]

Here is last weeks group, I was dialed 1 mil up to shoot the group, just FYI

 

[Ucsdryder]

Can you move back to 800-1000? Curious to see if the trend continues.

 

[BBob]

6” error within 65 yards? Something’s wrong. Your drop table is right and your not going to be able to true a 6” error in 65 yards without everything else going to hell.

 

[Rugger7622]

It's not 65 total yards, 500 was good 565 was 6". I can't get back any further around me, 565 is the longest. I'll shoot again this week and see if it continues.

 

[Lawnboi]

It's not 65 total yards, 500 was good 565 was 6". I can't get back any further around me, 565 is the longest. I'll shoot again this week and see if it continues.

Semantics; what he’s saying may not have matched what you thought but the statement is true.

If you’re having to change MV that much, for a Berger hybrid, at times of flight that low, you need to be assessing other things.

 

[Rugger7622]

Fair point, thanks and I agree, just doesn't make sense to me that 100, 300 and 500 were good and 565 was 6" high. I'm pretty sure it's me, but I can't seem to figure out what I did.

I'll go at it again and see if it repeats.

 

[BRTreedogs]

Here is last weeks group, I was dialed 1 mil up to shoot the group, just FYI View attachment 902243

So you are saying this picture is of a 100 yard zero, dialed up 1 full mil?

And it’s only approximately 1.5” high?

A mil is approximately 3.6”


You need to start over.