Quick Maths (Easy bullet drop calculations)

[Sampo]

T

Scope is above the bore, usually by between 1.5 and 2 inches.

So bullet leaves barrel well below line of sight, travelling upward. It takes some distance for it to cross the line of sight, and until it does, it will hit below the point of aim. At very close range, this can be quite a lot lower. So at close range you need to aim high.

For most people with a 100m zero, it’s really only the first 20-30m where this is a noticeable issue. For instance, a head shot at 10-20m can go low enough to cause a problem if not adjusted.

Thanks everyone for the explanation. Did learn something new today.

 

[NullMac]

Might be of use to some, definately shows the benefit of the Mils system vs MOA!

Applies to most rifles between 2,500-3,000fps shooting a bullet between G1 0.4-0.6 BC

Actually it works for MOA just fine if you change the 200 yard multiple to 2.34x. Everything else is within the usual tolerance.

The concept will work with any unit you just need a different set up multipliers as it is working on the basis of the time of flight being relatively constant. It is an observation that gravity is constant and if the velocities and bc's are similar then the drop ratios will be similar irrespective of what you are actually shooting.

Useful for the PRS guys I guess to get initial hits on paper and then fine tune. Most of use would just use our ballistics app ?

Probably a preppers dream as they are always fixating on what happens when the batteries run out ?

 

[User00040]

Actually it works for MOA just fine if you change the 200 yard multiple to 2.34x. Everything else is within the usual tolerance.

The concept will work with any unit you just need a different set up multipliers as it is working on the basis of the time of flight being relatively constant. It is an observation that gravity is constant and if the velocities and bc's are similar then the drop ratios will be similar irrespective of what you are actually shooting.

Useful for the PRS guys I guess to get initial hits on paper and then fine tune. Most of use would just use our ballistics app ?

Probably a preppers dream as they are always fixating on what happens when the batteries run out ?

Yeah, I know how to do a rough Mil-Moa conversion, but the above system is ideal for getting almost any centrefire 'on target' within 500 yards. Fine tuning can be done after the first round impact is spotted.

 

[NullMac]

Gravity Ballistics app available for android and apple on the app stores...