Mil values on SFP variable power scope

obsessed1 · #1 03-31-2018, 07:40 AM

Hey all, does anyone know the formula to figure out what the value of 1 mil would be when on say 6x if the scope is SFP and calibrated at 18x. Im trying to build a quick cheat sheet reference card for ranging coyotes using my mil reticle in comparison with the coyotes chest(13") and the like stadia lines. The scope is a 6-24 and calibrated at 18x but I always call while on 6x.
I am aware of how to properly range with my reticle but in a hunting situation I find it takes way too long.
I have a range finder but it's just another thing banging around my neck/ pocket and using it causes extra un needed movement

I know I can set up a sheet of plywood and check it at different ranges but the snows still quite deep out here and figured I could do it mathematically first then verify.

Thanks

hogie · #2 03-31-2018, 08:50 AM

Generally most scopes are are set to be at the highest setting of magnification to be accurate with reticle. There are some exceptions to this. I had a Bushnell 6x24 scope that it was setting 12 that the reticle was accurate. Go to 24 then 1 mil would be .5 mil, on 6 1 mil would be 2 mil. My Nightforce 5.5x22 works the same. On 22 reticle is correct ,11 1 mil is 2mil, 5.5 1mil is 4mil.

It seems odd that your 6x24 would be accurate at 18 power. If it is then at 9 it should be correct that 1mil would be 2 mil. The only way to figure out what it will be on 6 is shoot it and figure it out.

Nyksta · #3 03-31-2018, 11:50 AM

1/3 the power means your reticle lines will be 3x the size..

1/2 power is 2x the size.

Lanzero33 · #4 04-01-2018, 09:43 AM

Quote:

Originally Posted by Nyksta

1/3 the power means your reticle lines will be 3x the size..

1/2 power is 2x the size.

Nice explanation so far. Thanks!

Dean2 · #5 04-01-2018, 10:46 AM

Quote:

Originally Posted by Nyksta

1/3 the power means your reticle lines will be 3x the size..

1/2 power is 2x the size.

This is correct and can be expanded to any power setting. That said, I find dividing the power 18 by the set power is easier. 18/9 power being 2 is 2 Mil, which is 7.2" or 3.6x2, at 1oo yards, Thus 4 power is 4.5 so 4.5x3.6 is 16.2" at 100 yards.

At 500 yards one mil is 18", on 24 power 18/24 is .75 or 13.5".

Nyksta · #6 04-01-2018, 02:18 PM

Thats a lot of conversions to wrap my head around. 1 centimeter per mRad per 100 meters is the quickest and most straightforward for me. Just have to think about target sizes in centimeters which sometimes has a quick conversion from inches. Deer vitals is about 20 to 25 cm

hogie · #7 04-01-2018, 08:19 PM

Quote:

Originally Posted by Nyksta

1/3 the power means your reticle lines will be 3x the size..

1/2 power is 2x the size.

And math was my worst subject. Never thought about thirds.

Dean2 · #8 04-02-2018, 09:54 AM

Quote:

Originally Posted by Nyksta

Thats a lot of conversions to wrap my head around. 1 centimeter per mRad per 100 meters is the quickest and most straightforward for me. Just have to think about target sizes in centimeters which sometimes has a quick conversion from inches. Deer vitals is about 20 to 25 cm

This one does not make sense to me. I Mil is 3.6" at 100 yards, so will be 3.937" at 100 meters, which is 10 centimeters, not one centimeter. This becomes 20 Cent at 200, 30 Cent at 300 and 100 Cent at 1000 meters. This is at the one specified magnification, unless you are using a first focal plane reticle. So no matter whether you use metric of Imperial you still have to convert for other magnifications, though multiplying by 10, 20, 30 etc might be easier for many.

Nyksta · #9 04-02-2018, 04:26 PM

Quote:

Originally Posted by Dean2

This one does not make sense to me. I Mil is 3.6" at 100 yards, so will be 3.937" at 100 meters, which is 10 centimeters, not one centimeter. This becomes 20 Cent at 200, 30 Cent at 300 and 100 Cent at 1000 meters. This is at the one specified magnification, unless you are using a first focal plane reticle. So no matter whether you use metric of Imperial you still have to convert for other magnifications, though multiplying by 10, 20, 30 etc might be easier for many.

Most mrad scope have 0.1 mrad clicks. 1 click is 1 cm at 100m. Pardon me if it was misunderstood. What is 0.1 mrad unit called?

Dean2 · #10 04-02-2018, 05:31 PM

Quote:

Originally Posted by Nyksta

Most mrad scope have 0.1 mrad clicks. 1 click is 1 cm at 100m. Pardon me if it was misunderstood. What is 0.1 mrad unit called?

Now I get what you are talking about, had not thought about the click value. Have to be careful though, not all Mil-Dot scopes have Milrad adjustments, some use MOA on hte Turrets, and some that do like Leupold the adjustment is .05 of a Mil instead of .1.

As to what to call .1 of a Mil: depends on where you are, some call it a Bip (North America), some a decimil (Europe), and rarely a perymyraid (literally one in ten thousand). usually only seen in England and commonwealth countries.

Nyksta · #11 04-02-2018, 06:13 PM

Quote:

Originally Posted by Dean2

Now I get what you are talking about, had not thought about the click value. Have to be careful though, not all Mil-Dot scopes have Milrad adjustments, some use MOA on hte Turrets, and some that do like Leupold the adjustment is .05 of a Mil instead of .1.

As to what to call .1 of a Mil: depends on where you are, some call it a Bip (North America), some a decimil (Europe), and rarely a perymyraid (literally one in ten thousand). usually only seen in England and commonwealth countries.

I tend to just call it clicks when it comes down to using it. If someone was going to use the mrad system then it would be worthwhile to make sure the reticle and turrets match. Very easy to use together.