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The Mildot Master, MILSPEC-XR, and Whiz Wheel - three inexpensive and reliable analog calculators for the practical long range shooter.

Introduction

While the are dozens of ballistic calculators for smart phones and rugged PDA's, analog ballistic calculators provide an inexpensive and reliable alternative for the practical long range shooter. Often used as a backup option, they can be used as the primary ballistic calculator.

Analog ballistic calculators have some significant advantages over those in phones or PDA's. They don't have batteries, so they are always available. They take up very little space and easily fit into a BDU pocket, or a sleeve in a sniper data book. And you don't have to worry about crushing the screen.

This article presents three analog ballistic calculators: Mildot Master, MILSPEC-XR FDAC, and the Whiz Wheel. 

Other information on this page:
Introduction
Mildot Master
Density Altitude
MILSPEC-XR FDAC
Whiz Wheel

To download an article by Todd Hodnett, Ballistics For Beginners, in Sniper Magazine visit Accuracy 1st Development Group at:

http://www.accuracy1stdg.com

For information about Sources Of Ballistic Program Inaccuracies read Linden B. (Lindy) Sisk at Arcanmaven at:

http://www.arcanamavens.com/LBSFiles/Shooting/

Mildot Master

Mildot Enterprises introduced the Mildot Master in 1998, and it has seen widespread use in the military and civilian shooters because it has a feature other analog ballistic calculators don't have - a target range calculator. This feature alone makes the Mildot Master a must-have item for anyone with a mil-dot style reticle. Simply slide the rule to the point where the target size is aligned with the mil estimation from the scope and just read off the target range. And if shooting on an inclination, just reread the range for the given angle.

The Mildot Master comes standard with one insert with:

• Target size in feet and inches, range in yards, and bullet drop in inches with a reverse side with,
• Target size in feet and inches, range in metres, and bullet drop in inches

An optional insert exists with:

• Target size in centimetres, range in metres, and bullet drop in centimetres

To use the Mildot Master as a ballistic calculator the shooter must prepare a drop chart for the conditions they will be operating in. Once the range is known, look at the drop chart and find the bullet srop for that range, then without moving the slide read the MOA or mils elevation adjustment required for that bullet drop. The maximum MOA calculation is 15.0 and the maximum mils calculation is 4.5, so for a .338 Lapua Magnum shooter this will be limited to distances of around 700m.

For those shooting high angles the reverse side of the Mildot Master has an angle calculator. Just tie a piece of string (with a split lead shot on it) to the corner, and sight along the edge.

To purchase a Mildot Master visit Mildot Enterprises at:

http://www.mildot.com/

The Mildot Master operates very much like a slide rule.

Mildot Master, front side.

Mildot Master, back.

Density Altitude

Long range precision shooters know that an aiming solution in one set of field conditions will likely be different in another set of field conditions, particularly with significant changes in altitude and temperature.

Mildot Master handles these changes by having the shooter create multiple drop charts. For example one drop chart for a site at sea level and another drop chart for a site at 700m altutude.

The MILSPEC-XR FDAC and Whiz Wheel don't require any drop charts. They both use density altitude (DA).

MILSPEC-XR includes a table on the back, where the density altitude is the interestion of the physical altitude and air temperature (F).

The Whiz Wheel includes a small wheel where the density altitude is the alignment of the physical altutude with the air temperature (F).

Both of these will result in some approximation of the DA, so the most accurate method for obtaining the density altutude is to use a Kestrel that has that function eg a Kestrel 4500NV.

For information about Density Altutude visit Wikipedia at:

http://en.wikipedia.org/wiki/Density_altitude

For information about Manual Calculation Of Density Altitude read Linden B. (Lindy) Sisk at 8541 Tactical at:

http://www.8541tactical.com/lindy/density_altitude.php

For information about Wind Meters And Environmental Stations For Tactical Shooting read Zak Smith at DEMIGOD LLC at:

http://demigodllc.com/articles/windmeters-for-tactical-shooting/

MILSPEC-XR FDAC

There are two analog ballistic calculators available from Adaptave Training and Consulting Services:

• Field Density Altitude Compensator (FDAC)
• MILSPEC-XR FDAC

The MILSPEC-XR FDAC comes with 12 slide inserts suitable for a rifle sighted in at 100m using:

• .300 Winchester Magnum
  • MK248 MOD 0 - 190gn Sierra MatchKing - Muzzle Velocities: 2900, 2950, 3000 fps (3 slides)
  • MK248 MOD 1 - 220gn Sierra MatchKing - Muzzle Velocities: 2800, 2850, 2900 fps (3 slides)
• .338 Lapua Magnum
  • 250gn Lapua Scenar - Muzzle Velocities: 2900-2950-3000 fps (3 slides)
  • 300gn Lapua Scenar - Muzzle Velocities: 2700-2750-2800 fps (3 slides)

Each card has a set of data for: -2000' DA, 0' DA, +2000' DA, +4000' DA, +6000' DA, +8000' DA, +10000' DA, +12000' DA, +14000' DA, and +16000' DA. The data covers: ranges from 100m to 1500m; angles of 0, 15, 25 and 35 degrees; and 1mph wind and lead.

Simply use the insert that has the closest match to the muzzle velocity for the rifle using that ammunition. For example an Accuracy International AWSM firing 250grain Lapua Scenar has a muzzle velocity of 2970 fps, so use the insert for 2950.

Calculate the DA, then slide the insert to that DA eg showing the +2000 DA data, and read off the elevation in mils.

To purchase a FDAC or MILSPEC-XR FDAC visit Adaptive Training And Consulting Services at:

http://www.actsvirginia.com/index.php

To read Gear Review: Field Density Altitude Compensator by Ian Kenny visit Accurate Shooter.com Bulletin at:

http://bulletin.accurateshooter.com/2011/05/gear-review-field-density-altitude-compensator/

MILSPEC-XR, front.

MILSPEC-XR, back, also has a table for calculating spin drift from 800m to 1500m.

MILSPEC-XR with all the inserts that it comes with.

Whiz Wheel

A whiz wheel is a term known to many pilots and even mortar crews but in this case Accuracy 1st Development Group have a developed a Whiz Wheel for practical long range shooters.

Various purchase options exist for the Whiz Wheel, including; military munitions, multiple wheels (eg different ammunition in the same rifle), or a custom wheel/s.

All Whiz Wheels are based on a 100yd / 100m zero, and covers ranges to 1550m. For a custom Whiz Wheel just specify the: bullet manufacturer eg Lapua, units for range eg metres, units for optics eg mils, calibre eg .338, grain weight eg 250, muzzle velocity eg 2970 fps, barrel twist rate eg 1:11, and scope height eg 2.2".

Calculate the DA with the small wheel, then turn the large wheel until the range shows in the window applicable to that DA, and read the mil adjustment for scope elevation. If high angle shooting use the table on the back to adjust for angles from 5 to 60 degress (in 5 degree increments).

For windage adjustments, and mover adjustments turn the Whiz Wheel to the back and move the large wheel to the range at that DA, and then read the values.

To purchase a Whiz Wheel visit Accuracy 1st Development Group at:

http://www.accuracy1stdg.com/

Whiz Wheel, front.

Whiz Wheel, back.

Disclaimer:  Shooting is potentially dangerous and damaged equipment can be expensive to fix.  You should confirm all changes to be made to your rifle system and shooting practices with your local gunsmith or gunshop owner.  The example and data above are provided for information purposes only.  No warranty is made for its suitability or use with your rifle.