SFP Question

[cea1960]

While out hunting I spotted a squirrel in a tree but only it's head was showing. I have the 3-12x32 Bugbuster set at 6x with a zero at 30 yards. I zoomed to 12x to get a more precise shot, but the squirrel took off before I could take the shot. 

I know that if a SFP scope is zeroed in at say 30 yards at 6x and then it's changed to 12x the mildots won't give the same holdover POI.

Will the zero still be the same, or does the scope need to be re-zeroed at 30 yards when set at 12x? 

 

[wyshadow]

Good question. My guess would depend on how good your scope shifts as you change magnification. Test it out and let us know

 

[vmaxpro]

On a cheap scope yes sometimes you will have a poi shift changing the zoom. Ive had scopes over 1500$ do it though but they got sent back. For the record, not one leupold or nightforce Ive ever owned moved with the zoom. Im shooting an athlon ares and it doesnt budge. Try it and see what happens

 

[Xbowsniper]

Cea1960,

With a Second Focal Plane scope, what you described is correct. If you zero at your distance, 30 yards in your case,, no matter what your magnification, 30 will always be dead on.. if you are shooting at a closer, or a further target other than 30 yards, you must use holdover. With a second Focal Plane scope, this is normal. Also, every magnification between 3 and 12, will have different holdovers at the same distance. This is normal as well.

A very important thing to remember when sighting in a second Focal Plane scope, is this:.........

When you sight in a scope, as you said, your zero is 30 yards, you must do so at the highest magnification your scope has, in your case 12x. When this is done, now when you reduce the magnification to a lower power, the scope will be dead on.

When someone zeros their scope in at 3x, and then goes to 12x, it might not be dead on at 12x, due to the magnification actually magnifying the error when zeroed at 3x. This is why one should always zero any scope at its highest magnification. This way, when backed off, it's still dead on.

If you have any scope that is sighted in properly at the highest magnification, and then zoomed down to the lowest magnification, and does not zero in the same place, something is wrong, and the scope is most likely defective, or an inferior cheap scope.

Tom Holland 

Field Target Tech 

 

[sonny]

The cross hairs dont change just the mil dots Way more in-depth knowledge 

 

[Redick]

Every scope I've ever had in SFP changed poi when changing magnification thats why I use ffp now

 

[cea1960]

Thanks to all for your replies.

Tom, that is a good point about sighting in at maximum magnification. I will definitely re-sight it in at 12x before my next outing.

Although the Bugbuster is no where near as clear as my Arken, it has never lost poi in the year and half it's been knocked around the woods and in the bed of the truck. Including a 4240 mile round trip across the country. Not bad for an $87 (on sale) scope that was a fill in until I could find a nice fixed 6x.