Slope Dope- Math, tools, and etc.

M

Medic88

Inactive
Hey guys, so here is one where I need a little help. Please forgive my lack of knowledge in this field.

I looked at the Slope Doper online in a pic and saw that it had a percentage and is easily done with a calculator using what it called the Slope Angle Factor. It says that there is a 13% decrease, or a Slope Angle Factor of .87, range difference on a 30* slope. 30* is what my fishing weight/string/protractor told me.

From this you can deduce that smart phone= field adaptability.

Example: If you are taking a 750yd shot then, 750x.87=652yds. That is what you would dial in for elevation correction right?

Atmospheric conditions<- for the program runners
Temp: 59* nice right?
Baro: 29.98
Humidity: 92%
Wind was a mild 6mph @ 3

With my 300 Win Mag running 185gr. Berger VLD's @ avg. 3126fps then drop at 750= 114" or 4.2 Mils and @ 650= 78" or 3.3 mils

I hit the 20"x20" plate by using the 650 however there is only a 5" diff in windage at that distance. Not know which one the bullet was actually travelling.

So one of my questions is which do I dial for and which one do I dial in my windage for? From my reading it would be corrected distance for elevation and sloped distance for windage.

I am trying to build my field pouch with stuff that will apply and this seems like it would be really apply.

Slope Doper seems to run off of the Slope Angle Factor. How true does this hold, across all ranges? Is this a generally known table, or one that I can make a table and carry, in long range shooting and easily obtainable? I took applied mathematics instead of trig so if someone wants to explain?

Thanks to all those smarter than me.
 
It's a travel time thing. The bullet is going downhill, so it doesn't slow down as quickly--which is why the 650 applies for the drop.

650 applies for the windage as well since the bullet is exposed to the side-push for the same length of time.

The calculation for the bullet's apparent range vs. the line of sight distance is the cosine of the angle. 0.866 for 30º; 0.7071 for 45º.

For the º symbol, hold down the Alt key while entering 167 in the right-side keypad. Release the Alt key and there you have it! º
 
sorry to be a troll,, but i had to try it.............but with laptop users, you gotta hold Fn+alt then 167
Click to expand...

That depends on the laptop, and how the motherboard sees the Function key. Some laptops are completely incapable of entering special characters. (...Such as this one.) I just do a quick web search for the character, and use copy/paste. For offline work, most word processing applications have special character lists, that can be browsed.
 
The "slope angle factor" is nothing more than the cosine of the angle.

Multiplying the distance by the cosine of the angle gives you the "true horizontal" distance to the shot instead of the line of sight distance.

Remember cosine equals adjacent over hypoteneus, so multiplying the distance (the hypoteneus) with adjacent/hypoteneus simply cancels out the hypoteneus and gives you the adjacent length. If you multiplied by the sine of the angle (opposite over hypoteneus), it would give you the vertical difference.

This will hold true across all ranges that your rifle can accurately fire, including uphill shots.

Jimro
 
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