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Taidog1
04-21-2024, 05:35 PM
I'm stepping from SFP into / learning dialing with MIL and FFP. I now have a question about my SFP hunting scope.

I've sighted in my SFP scope @ 100 yards (or 200) using the 15x power setting. Done. Good groups.

Now - I go to the range or field and change my power setting to 6x (or 4x or 10x). I don't touch my elevation or windage trurret. Will my POI - my accuracy - hold at 100? I'm not talking about bullet fps and trajectory ballistics - just POI at 100 at a diffent power setting. I've spent a lot of years believing I knew this. And I MAY be right that POI will hold at different power settings on my scope?? Right?? Killed a good bit of game at many yardages doing this. Always worked.

I just want to make sure I have this right.

Thank you. Much appreciated.

Whynot
04-21-2024, 08:16 PM
I'm stepping from SFP into / learning dialing with MIL and FFP. I now have a question about my SFP hunting scope.

I've sighted in my SFP scope @ 100 yards (or 200) using the 15x power setting. Done. Good groups.

Now - I go to the range or field and change my power setting to 6x (or 4x or 10x). I don't touch my elevation or windage trurret. Will my POI - my accuracy - hold at 100? I'm not talking about bullet fps and trajectory ballistics - just POI at 100 at a diffent power setting. I've spent a lot of years believing I knew this. And I MAY be right that POI will hold at different power settings on my scope?? Right?? Killed a good bit of game at many yardages doing this. Always worked.

I just want to make sure I have this right.

Thank you. Much appreciated.

Yes- the center crosshair point of aim does not change when you adjust the power... doesn't matter if you are on lowest power or highest power.

What does change are the subtensions (the reference points below the center crosshair) as you change magnification. (if you only have a duplex reticle then this doesn't apply). But if you have a reticle that has different aiming points- be it a mil, moa, or bdc- then those additional aiming points and wind holds are only correct at one magnification.

Think of it this way- if you are looking at a target and from top to bottom it covers 4 moa lines at max power.... now you power down. Because you decreased power the target now appears smaller- but the reticle did not change so it now only covers 2 moa lines. That is how a sfp scope works... if it has a .2 mil reticle set to be correct on 20x then those reticle marks will actually become .4 mil if you adjust the power to 10x.

FFP changes the size of the reticle as you adjust the power- so if you are looking at a target that is 2 mil on 20x and zoom down to 4 power the target would still cover the same 2 mil on your reticle.

Taidog1
04-22-2024, 10:57 AM
Yes- the center crosshair point of aim does not change when you adjust the power... doesn't matter if you are on lowest power or highest power.

What does change are the subtensions (the reference points below the center crosshair) as you change magnification. (if you only have a duplex reticle then this doesn't apply). But if you have a reticle that has different aiming points- be it a mil, moa, or bdc- then those additional aiming points and wind holds are only correct at one magnification.

Think of it this way- if you are looking at a target and from top to bottom it covers 4 moa lines at max power.... now you power down. Because you decreased power the target now appears smaller- but the reticle did not change so it now only covers 2 moa lines. That is how a sfp scope works... if it has a .2 mil reticle set to be correct on 20x then those reticle marks will actually become .4 mil if you adjust the power to 10x.

FFP changes the size of the reticle as you adjust the power- so if you are looking at a target that is 2 mil on 20x and zoom down to 4 power the target would still cover the same 2 mil on your reticle.

Whynot...

Thank you very much for the confirmation and plain language explanation. What you said after your text in red above..........I'm still learning. Definitely a work in progress. I'm sold on FFP MIL for LR "target" work - for all the good reasons.

Just not sure I need a FFP MIL scope for Hunting??? Over many long years, the game I've taken have been inside 400 yards. That said...knowing how to dial correctly would be an advantage down the road should I only have an ethical LR opportunity.

Have a good day.

Cheers!!!