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Support Equipment For PCP/HPA/CO2 and springers ,rams => Optics, Range estimation & related subjects => Topic started by: jjohnsonlta on June 04, 2023, 09:59:00 AM

Title: Are AO and SF scopes necessary?
Post by: jjohnsonlta on June 04, 2023, 09:59:00 AM
I found this post subject on AGN and thought it was pretty interesting. https://www.airgunnation.com/threads/are-a-0-and-s-f-scopes-necessary.1278982/ (https://www.airgunnation.com/threads/are-a-0-and-s-f-scopes-necessary.1278982/)         

I am currently using a Hawke 3-9x40AO scope on my Stoeger 22 cal Bullshark Bullpup.  I use this gun for both hunting and target shooting. I was finding that I was not having the time to adjust the scope when hunting at various ranges and really wanted a point and shoot gun setup. After some study like the above post I decided on getting the Hawke 4x32 non AO scope.

The post on AGN explained this subject pretty well and showed different opinions on what works best for people. The suggestion of just setting my current scope to a fixed lower magnification probably would have worked but I wanted the benefit of the lighter and simpler scope. This post also answered  this subject pretty well for me.

   
Title: Re: Are AO and SF scopes necessary?
Post by: Back_Roads on June 04, 2023, 10:34:24 AM
 Depending on intended use and weight and distance requirements, I do have many guns set up with simple optics. Along with others dedicated to distance shooting and extreme precision needs, with variable power and focus adjustments.
Title: Re: Are AO and SF scopes necessary?
Post by: Hoosier Daddy on June 04, 2023, 11:31:08 AM
I have a couple Non AO scopes that get used from time to time... the are OK but they are scopes like CP's that came with airguns so I believe they are set to 50y.
PB Non AO's are usually set at 100y.  ;)
 My one and only Hawke is Non AO Sport HD 3-9X40 and it is simply amazing at 30Y... been on a NP Benjamin Springer that ain't no slouch for 5 years.

As far as Side Focus goes, yeah it's nice... when I buy a new scope I look for that but is not a show stopper. I don't mind turning the end-bell if needed.
But a Sidewinder with a wheel is so stinking easy!!!  8)
Title: Re: Are AO and SF scopes necessary?
Post by: c_m_shooter on June 08, 2023, 10:59:36 AM
The biggest factor in Parrallax error is objective diameter.   If you get a 20mm scope the error is undetectable until inside of 15 yards.  I have verified this with my Leupold 1-5x with the factory 150 yard parrallax setting.



Title: Re: Are AO and SF scopes necessary?
Post by: TorqueMaster on June 09, 2023, 03:50:27 PM
I'd say you're right -- larger objectives increase the error possible, but mismatched parallax setting and shooting distance is what causes it.  If you stick on a scope parallax fixed at 100 yards, and shoot at 25 yards, it's pretty bad by airgun standards.  This useful equation, stolen from:
https://www.lelandwest.com/parallax-error-calculator.cfm (https://www.lelandwest.com/parallax-error-calculator.cfm)

Parallax error in millimeters (Pmm): ( 0.5 x D x ( Abs ( R - P ) ) / P
    D = Objective diameter in millimeters
    R = range to target
    P = fixed parallax setting of scope

Below is chart for a 20mm scope.  If you are using a 40mm scope, yes, all numbers would be doubled!  This is worst case with your eyeball way off to the edge of the scope image.  The good news is -- if you can keep your eye consistently well centered in the scope, you won't have "any" error.  Also worth noting, if you set your parallax way too close, say 25 yards, then shoot at 100yards, this is WAY worse for potential error than having parallax set for way way too far past the target. 

Anyway, for point-and-shoot, I'd set the parallax at or just short of your maximum taking range, zoom where you like it, and not fiddle with it unless you have time.  A pre-set parallax 50 yard scope would be ok, 100, less so.  The weight savings from non-AO, and depth of field (and field of view (and brightness)) from lower magnifications all factor in, too...

 

Title: Re: Are AO and SF scopes necessary?
Post by: bear air on June 09, 2023, 04:37:15 PM
I recently bought a lpvo and am checking the waters right now. Its only a 1-4 so it's way different than the 3x12 with ao that I had on it.
Title: Re: Are AO and SF scopes necessary?
Post by: lefteyeshot on June 09, 2023, 05:18:50 PM
I usually shoot 25-50 yards, sometimes 75. I don't think it make much difference. Just something else to break. Last few years I've been buying two different scopes at Wal mart figuring they would be easy to exchange. But none have broke. They do the job. I've had 5 Hammers break.

Simmons Protarget 30mm 3-9x40 mildot $54
CP 3-9x32 mildot lum $54
Title: Re: Are AO and SF scopes necessary?
Post by: Yogi on June 09, 2023, 11:04:00 PM
If you want to hit what you are shooting at regularly get a adjustable parallax scope that "focuses" down to 10 yards and has hash marks for hold over/under.
Do you HAVE too, no but it sure makes things easier.

-Y