Scope bracketing and true power level

[josh3rd]

I have a AirMax30SF and compete in HFT with a AA Prosport. 

First is it 10 or 12 power that it's, I guess the word is, "calibrated" for or for it's reticle to be 3.6" from center mildot to center of next mildot at 100yds?

Secondly, after finding if it's either 10 or 12 power to be true at 100yds, for argument sake, say it's 10x. Well at 25yds, it should measure .90"? And what is the closest ruler marking for .90"? 7/8"? Or should I use 23mm? 

Now for bracketing. If a brick is 7.2 inches and it spans 2mil at 100yds, does that mean 4mil at 50yds and 8mil at 25yds? At the 10 or 12 power the Airmax is true at. 

If so to all of the above,then what would it be on 16 power? Reason I'm asking is because at the moment, since I moved to Delaware,I only have access to 25yds. I will hopefully be able to continue my range card for 30yds and beyond in the near future but just for bracketing sake.

Hopefully I am making sense with all this. Looking forward to seeing your feedback.

Cross posted

 

[jwrabbit123]

ok i think you asking how to caculate a second focul plane scope ,

Ok so if it was a 5 x20power scope and is calibrated in MIls at 10x , then if you shoot it at 5x each mil dot would be 2 mils or 7.2 inches between mil dots and same goes if you shot it at 20x then each mildot is 1.8moa per mil , and going to say 7.s x or using 15x then it would be = or - .75 of value for each mildot ,

When using scope for bracketing or ranging the FFP scope is much better as no matter which power level it is still true moa or Mile radians , years ago alot of lower end scopes and most of hawks used to be mix mated reticles meaning reticle was in mils or moa and turrets were opposite of the reticle , This mismatched and sfp makes caculating very difficult , I mean you cant BREAK OUT A CALCULATOR OR PEN AND PAPER AND DO CALCULATIONS by then your target would be gone or if it was a zombie you would be toast , Best advice I can say if you like mismatched leave it on what is the true mils and dont touch it as even being off a little can cause misses at longer ranges and remember if you dail many cheaper scopes do not dial true moa or mils at different zooms I have tall tested many scopes and saw errors on turrets and repeatability ,

LOU

 

[Franklink]

I think you'll get further with this question if you put it in the field target area.

I shoot field target but have not done any bracketing as the clubs where I shoot use all sorts of combinations of screwing the targets to trees/stumps, staking them out in the ground, and sometimes bricks. The SOMETIMES is the kicker that has kept me from the bracketing business. One thing you could do is real-world comparisons though. Get a cinder block of the same size your club will be using (half or full) and look at it through the scope at various known distances, making notes of how much space it fills between hash marks in your reticle at those known distances. 

 

[AirShot]

Ouch....all that technical stuff is creating a headache !!! My electronic rangefinder is so much easier....

 

[mh]

Which of course he can’t use in HFT