TT and Vortex Gen3 in PRS

[ma smith]

The most plausible question is probably that riflescopes do not really shift zero with temperature very much if at all.

There's tons of stuff than can legit shift zeros in a match, from light quality in am/pm, to mirage, to velocity migration, etc. these may or may not also correlate to ∆temp˚ readings. ...

IMHO...

The issue here is having a plausible mechanical explanation, limited to a single optic/SKU, from a single OEM around the optic.

That of course needs some kind of evidence or observations, that the existence of or extent of... remain unclear or unkown....

It seems like the parallax function is the most misunderstood of any scope function.

Wait, is it 'parallax' or 'side focus'...or...

J/K

 

[GenericBadGuy]

However, I talked to Vortex about the issue and they tested all of Bakers scopes from below freezing to boiling point and could not recreate the issue. Just being transparent.

 

[koshkin]

In seeing the whole story I call BS on this whole "thermal shift problem" with the Gen III. As most know I have no love for Vortex now but not going to jump on some made up bandwagon of something that has never been seen in any other scope and all of a sudden just this scope has it happen. Seeing the rest of the story in shooters claiming this hurt them and having shot this sport over 20 years and seen people come up with all sorts of reason why they shot bad (Hint- it's always the gear and never them). Not even going to entertain this BS anymore.

And Ilya I wouldn't even waste a minute trying to prove this.

I am going to experiment a little bit with it since I am curious. I will be surprised if I find anything because from what I know of how riflescopes are built (riflescopes in general and this riflescopes specifically), we should not be seeing zero shifts due to temperature.

This is mostly to satisfy my own personal curiosity. It will either confirm that my understanding of what is happening inside a scope is correct or I will learn something new.

Since I do not know the shooters involved personally, I do not have any opinions on whether they sincerely believe the scope was the issues or whether they are simply out to slander Vortex.

ILya

 

[Cody S]

where is this podcast or whatever of people gossiping about vortex? quick search came up empty so far
I also might "downgrade" from a gen 2 razor to a gen 3 if I find the right buyer lol

 

[308pirate]

This bullshit story is one more example of the appeal to authority logical fallacy.

 

[stanley_white]

This bullshit story is one more example of the appeal to authority logical fallacy.

I take this card deck with me during meetings at work.

https://thethinkingshop.org/products/critical-thinking-cards-deck

-Stan

 

[jthor]

View attachment 8455679

What?

 

[oso1]

In seeing the whole story I call BS on this whole "thermal shift problem" with the Gen III. As most know I have no love for Vortex now but not going to jump on some made up bandwagon of something that has never been seen in any other scope and all of a sudden just this scope has it happen. Seeing the rest of the story in shooters claiming this hurt them and having shot this sport over 20 years and seen people come up with all sorts of reason why they shot bad (Hint- it's always the gear and never them). Not even going to entertain this BS anymore.

And Ilya I wouldn't even waste a minute trying to prove this.

You too often come into this threads and ruin them with common sense and logic

 

[diggler1833]

From ~ 25 degrees F late this winter to sitting out in the sun in 98 degree weather over this last week to the point where everything metal on the rifle was hot to the touch...I have experienced no shift with my G3 Razor.

Not saying it is impossible, just saying that in my small sample size of (1) that I haven't seen it.

 

[Cody S]

I don't believe it, but I'd still like if someone could direct me to where people are badmouthing vortex.
I'm bored and I'd like to know why.
still gonna be a vortex fanboy.

 

[Covertnoob5]

I don't believe it, but I'd still like if someone could direct me to where people are badmouthing vortex.
I'm bored and I'd like to know why.
still gonna be a vortex fanboy.

Conversations at matches not on a podcast or something.

 

[koshkin]

I'll be kicking off a livestream in half hour to discuss thermal effects in riflescopes.
Tyler Patner will join for a while. FIeld Target shooters have been paying attention to this for a while, so I want to pick his brain.
It will be on Youtube, Facebook, X and my Locals page. Here is the link to Rumble
It will pop up on Youtube once I start the stream.

ILya

 

[M8541Reaper]

Everyone who shoots in PHX in the summer can probably attest to temp not shifting the optic’s zero. Shit goes from 85F to 115F

 

[taliv]

@koshkin You have mentioned the term field target shooters… never heard of this discipline. Who are they and how is what they’re doing different? Why would they be paying attention to thermal effects that aren’t happening to PRS shooters who are also in fields shooting targets?

 

[hlee]

@koshkin You have mentioned the term field target shooters… never heard of this discipline. Who are they and how is what they’re doing different? Why would they be paying attention to thermal effects that aren’t happening to PRS shooters who are also in fields shooting targets?

“Field target shooting” is a specific shooting discipline using air rifles.

https://www.aafta.org/

 

[taliv]

Ok so why would air rifles be different? Just super close parallax? Different recoil?

 

[koshkin]

Ok so why would air rifles be different? Just super close parallax? Different recoil?

They use side focus wheel to measure distance and adjust for drop based on that.

Tyler goes over it for a few minutes:

Field Target is a hideously difficult shooting discipline from a shooting standpoint and that is one of the reasons.

ILya

 

[Rob01]

Seems like it’s similar to NRL Hunter and what we used to do before PRS became barricade benchrest.

 

[koshkin]

Seems like it’s similar to NRL Hunter and what we used to do before PRS became barricade benchrest.

Field Target is unsupported. You can adjust side focus, magnification and turrets as you shoot through the course, but no bipods, tripdods, etc. Field Target Hunter allows some support, but the optic can be no more than 16x and once you start the course, you can not adjust magnification, side focus or turrets.

ILya

 

[Rob01]

Field Target is unsupported. You can adjust side focus, magnification and turrets as you shoot through the course, but no bipods, tripdods, etc. Field Target Hunter allows some support, but the optic can be no more than 16x and once you start the course, you can not adjust magnification, side focus or turrets.

ILya

Ah I saw the pic of a tripod being used so thought that was how it was run. So you can't use a sling either seeing it's unsupported?

By "start the course" in hunter do you mean the stage of fire or the whole match? If the whole match then that's actually kind of ridiculous.

 

[koshkin]

Ah I saw the pic of a tripod being used so thought that was how it was run. So you can't use a sling either seeing it's unsupported?

By "start the course" in hunter do you mean the stage of fire or the whole match? If the whole match then that's actually kind of ridiculous.

I am not sure of the whole range of specifics, since I do not shoot FT. I was going to, but then I moved out of California and a whole other range of possibilities opened to me. I keep on meaning to get back to it, so I'll work out the details.

I do not think they use slings in FT, but they occasionally use straps to help contort their bodies into some semblance of support for the rifle.

ILya

 

[steve123]

I used to shoot a centerfire field course match in AZ and would win quite a few of these matches.
What I would observe was a shift in vertical of .2 mil at distance when the wind was blowing around 10 to 15 mph full value.

Also saw a huge vertical shift at a friend's place when the wind was blowing hard into us. This location is near the top of hill. I thought my scope was broken but when I went back later that week to test all was normal again.

Both times we were shooting near the top of a hill so I blame these odd conditions for exaggerating the poi.

I've shot airgun FT for almost a 1/4 century. There is a small amount of shift in scopes as far as image focus at various temperatures but it is different from scope to scope. This affects the 12 fpe WFTF shooters more than the 20 fpe shooters. I've won state 7 times without accounting for this affect but it was done in 20 fpe divisions.

 

[steve123]

@koshkin You have mentioned the term field target shooters… never heard of this discipline. Who are they and how is what they’re doing different? Why would they be paying attention to thermal effects that aren’t happening to PRS shooters who are also in fields shooting targets?

As far as heat is concerned there's more to it than just the scope being affected in FT.

Pcp air rifles are notorious for poi shifting. It can be a frustrating combination of things or just one thing. All which need to be narrowed down.

It used to be we'd cover our guns or put them in a gun case so they weren't baking in the sun and it does help lessen shifting. Guns have been getting more stoutly built though nowadays. Look up MAC1 USFT, it's super robustly built and mine was a problem free rifle. So is my Thomas FT rifle.

 

[steve123]

Ah I saw the pic of a tripod being used so thought that was how it was run. So you can't use a sling either seeing it's unsupported?

By "start the course" in hunter do you mean the stage of fire or the whole match? If the whole match then that's actually kind of ridiculous.

There is often an outlaw non AAFTA recognised division called "unclassified ". A tripod can be used which I did for a few years.

In Hunter division shooting sticks or a unattached bipod are allowed.

Gets a bit silly the rules in the various divisions.

 

[Huskydriver]

Heard it at a match the shooter who tried to get the don had a vortex and got some thermal shift

 

[steve123]

I am not sure of the whole range of specifics, since I do not shoot FT. I was going to, but then I moved out of California and a whole other range of possibilities opened to me. I keep on meaning to get back to it, so I'll work out the details.

I do not think they use slings in FT, but they occasionally use straps to help contort their bodies into some semblance of support for the rifle.

ILya

The contraption of straps you are referring to is called a "shooting harness". It supports the back and is pretty comfy to use when shooting in the sitting position and provides a much steadier aide than a sling.

Fun pre PRS and NRL story - About 15 years ago Ryan Kerr was able to get into what I call a "gumby" position. This is almost laying down forward while sitting then being fully supported with both elbows on the ground. He'd always win the sitting stages. So the Phoenix club decided to run a rope across the line in front of us for the sitting position stage with the new rule that the muzzle had to be above the rope. BTW I wasn't involved in this decision at all although I used to tease Ryan some about it.

Then one time in a sitting stage I decided to game it and use my harness and bum bag like I do in FT, LOL! Nope they saw me coming up to the line with the contraption and told me no it wasn't allowed so I didn't use it although it was still attached on me so I threw the bum bag(also used in FT) onto the ground to sit on when it was go time and they were kicking the bum bag out from under me, LOL! I'm looking back at them yelling at me thinking what the heck are you doing. I got the picture that it wasn't allowed either. Nice try on my part though.

 

[Rob01]

The contraption of straps you are referring to is called a "shooting harness". It supports the back and is pretty comfy to use when shooting in the sitting position and provides a much steadier aide than a sling.

Fun pre PRS and NRL story - About 15 years ago Ryan Kerr was able to get into what I call a "gumby" position. This is almost laying down forward while sitting then being fully supported with both elbows on the ground. He'd always win the sitting stages. So the Phoenix club decided to run a rope across the line in front of us for the sitting position stage with the new rule that the muzzle had to be above the rope. BTW I wasn't involved in this decision at all although I used to tease Ryan some about it.

Then one time in a sitting stage I decided to game it and use my harness and bum bag like I do in FT, LOL! Nope they saw me coming up to the line with the contraption and told me no it wasn't allowed so I didn't use it although it was still attached on me so I threw the bum bag(also used in FT) onto the ground to sit on when it was go time and they were kicking the bum bag out from under me, LOL! I'm looking back at them yelling at me thinking what the heck are you doing. I got the picture that it wasn't allowed either. Nice try on my part though.

That was an OK boys technique used a lot with the sitting and the rifle across the foot and elbows on ground. Saw them do it a bunch but I don't bend that way. lol

 

[steve123]

That was an OK boys technique used a lot with the sitting and the rifle across the foot and elbows on ground. Saw them do it a bunch but I don't bend that way. lol

LOL, same here. I'm the opposite of limber.

 

[Emerson0311]

I am not sure of the whole range of specifics, since I do not shoot FT. I was going to, but then I moved out of California and a whole other range of possibilities opened to me. I keep on meaning to get back to it, so I'll work out the details.

I do not think they use slings in FT, but they occasionally use straps to help contort their bodies into some semblance of support for the rifle.

ILya

So the FT shooters are more precise shooters than barricade bench rest? It seems like their style of shooting would add many more reasons for missing due to positions rather than optics shortcomings. The more solid the rest/bench/support the easier to track when the scope is “shifting zero” no?

 

[Tx_Aggie]

So the FT shooters are more precise shooters than barricade bench rest? It seems like their style of shooting would add many more reasons for missing due to positions rather than optics shortcomings. The more solid the rest/bench/support the easier to track when the scope is “shifting zero” no?

FT shooters shoot unknown distance targets without the aid of a LRF, and so use the parallax wheel on their scope to range the target. I think because of this they’ve become really concerned with how temperature can affect rifle parallax setting, since large shifts in parallax can result in them mis-ranging a target.

 

[Emerson0311]

FT shooters shoot unknown distance targets without the aid of a LRF, and so use the parallax wheel on their scope to range the target. I think because of this they’ve become really concerned with how temperature can affect rifle parallax setting, since large shifts in parallax can result in them mis-ranging a target.

Ah, ok, that makes sense. So like Ilya was saying, more likely a parallax issue that a zero shift.

 

[CK1.0]

This thermal shift thing has been bugging me for days now and I can't shake the feeling that there's probably a simple explanation.

Then this guy says:

As far as heat is concerned there's more to it than just the scope being affected in FT.

Pcp air rifles are notorious for poi shifting. It can be a frustrating combination of things or just one thing. All which need to be narrowed down.

It used to be we'd cover our guns or put them in a gun case so they weren't baking in the sun and it does help lessen shifting.

Just spitballing here, but:

Is it just a coincidence that Baker and Zane both run full-aluminum chassis and both have allegedly had problems? Could it be the chassis that are shifting in the sun? Metal moves (expands) when it gets hot.

 

[koshkin]

This thermal shift thing has been bugging me for days now and I can't shake the feeling that there's probably a simple explanation.

Then this guy says:


Just spitballing here, but:

Is it just a coincidence that Baker and Zane both run full-aluminum chassis' and both have allegedly had problems or is it just because metal moves when it gets hot (because it does)..? Could it be the chassis' that are shifting in the sun?

It is unlikely. Very unlikely. I suspect Rob's take on it is spot on.

ILya

 

[Vivacious Stallion]

Shot a local-ish to me field style match in the desert yesterday with my Gen 3. Started at 65 °F and ended at 104 °F according to my car. Gun and scope were in the sun for the entire time due to no real shade. Never saw any zero shift or issues and shot a 61/70.

 

[308pirate]

Is it just a coincidence that Baker and Zane both run full-aluminum chassis and both have allegedly had problems? Could it be the chassis that are shifting in the sun? Metal moves (expands) when it gets hot.

Nobody who has a financial skin in this game is going to admit that mating a steel barreled action to an exposed aluminum beam is a problem when both get very hot.

 

[steve123]

So the FT shooters are more precise shooters than barricade bench rest? It seems like their style of shooting would add many more reasons for missing due to positions rather than optics shortcomings. The more solid the rest/bench/support the easier to track when the scope is “shifting zero” no?

FT is much like the other rifle shooting sports. The most common reasons for a miss is either getting the wind wrong or making a mental mistake of some kind. However in FT there are often a few standing and kneeling shots so whoever is better at positional usually gets the winning score in their division or the match high score.

The pellets we use have a G1 BC of approx .030 which causes these projectiles to blow more than one would think in the wind, like 3-4 times more than a 22rf would. As far as an MOA size at distance the 'Kill Zones' as we call them aren't particularly small. A fun and quiet shooting game it is, almost relaxing sometimes. Way less pressure felt than during PRS type matches.

 

[MikeMiller]

What most people confuse for zero shift is because of one of a few things

Atmospheric conditions changed and impact is high or low based on what the temp did I remember shooting many long range matches where my morning base zero was more elevation dialed on than my afternoon base zero

Mirage gives the shooter a false location for the target. Because the water vapor changes the way you see the target you will change your aiming point. Hence making you think the zero is off. It can be up or down depending on sight in versus shooting conditions. Add a very slight wind and it will go slightly left or right as well

Ammo temp has changed and pressure/velocity has gone up or down. Changing impact up or down

 

[stanley_white]

This thread is robbing me of something to blame other than myself for my inaccuracy.

Damn you all.



-Stan

 

[TheOE800]

This thread is robbing me of something to blame other than myself for my inaccuracy.

Damn you all.



-Stan

Can’t blame your gun now either, AI boy!

 

[carbonbased]

Reading this thread, I was initially feeling all smug and self-satisfied with my two GenII’s.

And then you fags swoop in with your fancy Vulcan logic and…

 

[louu]

This thermal shift thing has been bugging me for days now and I can't shake the feeling that there's probably a simple explanation.

Then this guy says:


Just spitballing here, but:

Is it just a coincidence that Baker and Zane both run full-aluminum chassis and both have allegedly had problems? Could it be the chassis that are shifting in the sun? Metal moves (expands) when it gets hot.

The scope is attached to the action witch is attached to the barrel, what's the chassis have to do with anything?

 

[rijndael]

The scope is attached to the action witch is attached to the barrel, what's the chassis have to do with anything?

If that were all that mattered, zeros wouldn't change when moving a barreled action from chassis to chassis.

 

[CK1.0]

The scope is attached to the action witch is attached to the barrel, what's the chassis have to do with anything?

...it's a giant piece of aluminum that may or may not flex when heated up. When stuff flexes the shit attached to it moves too.

(btw, spitballing = taking a guess)

IDK what causes the phenomenon, or if there really is a phenomenon. It's most likely just BS.

 

[koshkin]

This thread is robbing me of something to blame other than myself for my inaccuracy.

Damn you all.



-Stan

I was disabused of that illusion years ago. When I miss, I know it is me.

ILya

 

[Hickswr]

I was disabused of that illusion years ago. When I miss, I know it is me.

ILya

WTH…..you guys miss???

 

[DairyDictator]

For what it's worth, I heard the issue was that the optics started tracking strong/weak when it heated up then returned when cooled, not necessarily a zero shift. Thought this could possibly be due to differing materials in the erector assembly.

That being said, I've only ever heard of it coming from the same two people mentioned in this thread. I have 3, two of which are black, and have not had such issues.

 

[koshkin]

WTH…..you guys miss???

Only during full moon.

 

[Spd37]

Where are the Gen 3’s made ?

 

[Islas82]

Where are the Gen 3’s made ?

Japan

 

[rothgyr]

For what it's worth, I heard the issue was that the optics started tracking strong/weak when it heated up

What is strong weak? Like too much elevation when dialing up, and fail to return to zero when it's hot? Or that turrets simply feel different if they're cold vs hot?