Scope temperature shift fixes

[JEFFPPC]

I have one question nagging me. So you focus with your parallex knob looking thru the atmosphere and come up with a distance. So if your go into the sun or conversley the shade or the temp changes the atmospheric condition has now changed. So looking thru it and focusing to it your going to get a different number. It's very common at 100 yards or 1000 yards every time you come to the bench you readjust your parallex but often your POI is not changed. So your dial gives you a different number because you adjusted To The Condition. . That makes sense to me. If the scope is physically changing internally dimensionly how could it Not change POI and some say it doesn't.

 

[JEFFPPC]

Temperature affects the way field target shooters use a scopes parallax adjustment to determine distance - the air volume in the scope tube IS affected by pressure changes from temperature changes so the scope doesn’t focus the same way when adjusting for parallax

And that change is happening in the air the entire distance to the target. So when you adjust to it you will get a different number. Your trying to make the scope to donating it is not designed for.

 

[JEFFPPC]

I don't wish to argue especially since I don't shoot FT but I think you guys are using the scope as a whipping boy because your trying to make it be something it was never intended to be . So you guys shoot a tough discipline, many very well, I will retreat, those who compete have my respect.

 

[cavedweller]

I don't wish to argue especially since I don't shoot FT but I think you guys are using the scope as a whipping boy because your trying to make it be something it was never intended to be . So you guys shoot a tough discipline, many very well, I will retreat, those who compete have my respect.

You are correct - we are using scopes in a way they were never intended to be used, yet that’s the game of field target.
Don’t ask me why or how this came to be, but someone may be able to shed some historical light on how this came to be. Currently we / I take a scope that can focus as close as 10 yards and using the parallax adjustment I mark a large parallax wheel at 1 yard increments for point of focus out to 55 yards. You really need to try field target as it’s really quite fun AND very challenging!
Notice the large ranging wheel in the picture

 

[cavedweller]

We use distance to determine poi based on actual shots fired at known distances or also using ballistic programs like StrelokPro; ideally the APP dope matches or actual shots taken dope. Anyway, come visit a field target event - great people!

 

[BackStop]

@BackStop - come visit us in pensacola Fl 1st Saturday of the month at Santa Rosa shooting center and we will introduce you to field target

I truly wish I could...

Thanks!

All my best!

Kerry