brand new to optics and pcp's...question

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Dan_Br

Member
Jul 11, 2018
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I will start off saying it could be me, but with my brand new and first PCP (Kral Puncher breaker .22) I am stacking pellets at 25 yds. Still hitting aim point at 35ish yds which is what ChairGun said should happen JSB.s (18.13 pellets)

Here is the question,

I zeroed my scope at 25 yds at 6 power, if I change to 13 power (the max) out at 34 yds, shots are lower .

Does that make sense or perhaps it is just me?

I am shooting off a front rest and rear of gun on back of my hand on table.

thanks in advance

dan
 
What scope do you have?

FWIW...Your pellet travels in an arc, due to gravity pulling the pellet towards the center of the earth. The barrel and the scope are not parallel in elevation. The barrel sits crown high in relation to the scope. The pellet will climb up to the apex, then begin to fall again. Where the pellet crosses the line of sight through the scope is the zero . On the way up (closer to gun) is the secondary zero...on the way down from the apex is the primary zero. You want to work on the primary zero.
 
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"A good scope should hold the poi throughout the entire magnification range. The key word here is "good". Check some of Joe Wayne Rhea's videos on scopes"

I am confused by this, can you clarify?

I thought this is only true for FFP, but POI will shift for SFP scopes if you change magnification, correct? If not, I need to go back to FFP vs. SFP school as I thought I understood that changing the magnification on FFP does not change POI, which I thought was the big benefit of FFP scopes. i.e, magnification can increase and decrease and you don't have to change hold overs. Target and reticle get bigger with increased magnification, but holdovers remain constant. 

In other words, a good scope should hold the POI for FFP scopes (not SFP) scopes for the entire magnification range? Do I have this correct?

Thanks
 
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"A good scope should hold the poi throughout the entire magnification range. The key word here is "good". Check some of Joe Wayne Rhea's videos on scopes"

I am confused by this, can you clarify?

I thought this is only true for FFP, but POI will shift for SFP scopes if you change magnification, correct? If not, I need to go back to FFP vs. SFP school as I thought I understood that changing the magnification on FFP does not change POI, which I thought was the big benefit of FFP scopes. i.e, magnification can increase and decrease and you don't have to change hold overs. Target and reticle get bigger with increased magnification, but holdovers remain constant. 

In other words, a good scope should hold the POI for FFP scopes (not SFP) scopes for the entire magnification range? Do I have this correct?

Thanks
Click to expand...


We're not talking about holdover. Let's say you zeroed the scope at 25 yards and 10X. If you stay at 25 yards and increase the magnification to 16X the POI should stay the same. Holdover is entirely different matter where different distances and magnification comes into play. FFP reticles stay the same size relative to the magnification.
 
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Anyone who says your scope should hold same poi throughout different magnification ranges must know zero about ballistics. Unless you have a first focal plane scope your poi will change due to magnification and angle it just depends how much. YouTube some stuff and watch Matt's videos before he came an FX slob and their very informative! It takes time and practice to learn it all 
 
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I think I understand.

Ok, so the key is that if both the zero and shooting distance are both at 25 yards, POI will not change even if you change magnification. That makes sense because your zero is exact at 25 yards - dead on.

But, if you zero at 25 yards at 10x magnification; and then “ Change shooting distance” to 40 yards and change magnification to 16x, POI will change right?

thanks
 
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A properly working scope will not change poi if it is hitting dead center of the crosshair at a specific range when the magnification is changed. When you start changing distance now that is a different story. Dan_Br I'm sorry to say your scope is not perfect but how many are? If you pick a magnification and study what your retical means there you should be fine. When you change magnification you will have to check zero 1st and then study what your retical means there as your markings change values when you change your magnification on an SFP scope, Bill.
 
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Anyone who says your scope should hold same poi throughout different magnification ranges must know zero about ballistics. Unless you have a first focal plane scope your poi will change due to magnification and angle it just depends how much. YouTube some stuff and watch Matt's videos before he came an FX slob and their very informative! It takes time and practice to learn it all
Click to expand...

Huh?

This is news to me. Can you point me to an article/video that explains this?

(Unless we’re talking about parallax, imperceptible distances or very inexpensive scopes)

Thanks 
 
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You scope may be malfunctioning, where the focal zoom is not in perfect alignment.



What kind of scope is it?
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the scope I purchased is UTG Pro 3-12x44 Compact Rifle Scope. It is a second focal plane scope. I am going to try again to zero at full magnification and then dial back. It could be me not having correct cheek weld and such, table is a MDR Predator folding table, good but not perfectly rigid.

thanks to all who responded

dan
 
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I will chime in and agree with others, a common problems on less expensive scopes include:

1. Point of impact changing with changes in magnification.

2. Point of impact changing with Ocular (eyepiece) adjustment.

3. Point of impact changing when your parallax is adjusted (even if it is correct for the distance)

4. Colored haze around the reticle when illuminated.

5. Chromatic aberrations (rainbow colors seen when looking at a black and white target in full sun).

6. The scope fails the "box test", lacks repeatability.

7. Scope drifts after a number of shots, especially notable on springer rifles.

8. Loose feeling knobs, some stiffness is a good thing, as long as it doesn't drag in certain positions.

9. A CenterPoint logo is found on it.

10. Just bad glass, hazy, excessively sensitive to glare. 
 
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