|
|||||
|
|||||||||||||||||||
Loads Per Pound of Powder |
Weight / Length Equivalents | Conversion Factors | |||||||||||||||||
Powder |
Loads | Powder |
Loads |
Powder | Loads | ||||||||||||||
5 gr. | = | 1400 | 40 gr. | = | 175 | 75 gr. | = | 93 | 7000 Grains | = | 1 Pound | Pounds x | 7000 | = | Grains | ||||
10 gr. | = | 700 | 45 gr. | = | 155 | 80 gr. | = | 87 | 437.5 Grains | = | 1 Ounce | Ounces x | 437.5 | = | Grains | ||||
15 gr. | = | 466 | 50 gr. | = | 140 | 85 gr. | = | 82 | 15.43 Grains | = | 1 Gram | Grains x | .00229 | = | Ounces | ||||
20 gr. | = | 350 | 55 gr. | = | 127 | 90 gr. | = | 77 | 25.4 Millimeters | = | 1 Inch | Grams x | 15.4324 | = | Grains | ||||
25 gr. | = | 280 | 60 gr. | = | 116 | 95 gr. | = | 73 | Grains x | .0648 | = | Grams | |||||||
30 gr. | = | 233 | 65 gr. | = | 107 | 100 gr. | = | 70 | Inches x | 25.4 | = | Millimeters | |||||||
35 gr. | = | 200 | 70 gr. | = | 100 | Millimeters x | .03937 | = | Inches | ||||||||||
|
Common Abbreviations |
|||||||||
|
|||||||||
ACP | > | Automatic Colt Pistol | HPBT | > | Hollow Point Boat Tail | SAA | > | Single Action Army | |
AV | > | Average Velocity | HS | > | Hydra Shok HP (Federal) | SD | > | Sectional Density or | |
BB | > | Bevel Base | J | > | Jacketed Bullet | Standard Deviation | |||
BBWC | > | Bevel Base Wadcutter | JHC | > | Jacketed Hollow | SIL | > | Silhouette | |
BC | > | Ballistic Coefficient | Core/Cavity | SJ | > | Short Jacket | |||
BP | > | Bullet Pull | JFP | > | Jacketed Flat Point | SP | > | Spire Point / Soft Point | |
BPS | > | Black Powder Silhouette | JHP | > | Jacketed Hollow Point | SWC | > | Semi-Wadcutter | |
BR | > | Bench Rest | KEITH | > | Elmer Keith Bullet Design | SSP | > | Single Shot Pistol | |
BT | > | Boat Tail | L/LB | > | Lead Bullet | TC | > | Truncated Cone | |
CAV | > | Cavalry | LBT | > | Lead Bullet Technology | T/C | > | Thompson Center Arms | |
CB | > | Cast Bullet | LD | > | Loading Density | TMJ | > | Total Metal Jacket | |
CF | > | Center Fire | LOS | > | Line of Sight | TOF | > | Time of Flight | |
CV | > | Coefficient of Variation | LRN | > | Lead Round Nose | WC | > | Wadcutter | |
CUP | > | Copper Units of Pressure | MC | > | Metal Case | WCF | > | Winchester Center Fire | |
DCM | > | Dir. Civilian Marksmanship | ME | > | Muzzle Energy | WLN | > | Wide Long Nose (LBT | |
FMJ | > | Full Metal Jacket | MOA | > | Minute of Angle | bullet design) | |||
FN | > | Flat Nose | MR | > | Mean Radius | XTP | > | Extreme Terminal | |
FP | > | Flat Point | MV | > | Muzzle Velocity | Performance, (Hornady jacketed | |||
FPS | > | Feet Per Second | NSS | North-South Skirmish | hollow point) | ||||
GC | > | Gas Check | OAL | > | Over All Length | ||||
HBWC | > | Hollow Base Wadcutter | PSI | > | Pounds Per Square Inch | ||||
HJ | > | Half Jacket | R/RB | > | Round Ball | ||||
HP | > | Hollow Point | RF | > | Rim Fire | ||||
RN | > | Round Nose | |||||||
|
Associations / Organizations Abbreviations |
Is Your Range In Meters Or Yards? | ||||||||||
CBA | > | Cast Bullet Association | Multiply: |
Abbreviations |
|||||||
CCA | > | Colt Collectors Association | Yards | By | 0.9144 | To get | Meters |
FPS |
> | Feet Per Second | |
IHMSA | > | International Handgun Metallic Silhouette Association | Meters | By | 1.094 | To get | Yards |
MPS |
> | Meters Per Second | |
IPSC | > | International Practical Shooting Association | FPS | By | 0.3048 | To get | MPS |
MPH |
> | Miles Per Hour | |
NBRSA | > | National Bench Rest Shooters Association | MPS | By | 3.281 | To get | FPS |
|
|||
NRA | > | National Rifle Association | FPS | By | 0.6818 | To get | MPH | ||||
NRMA | > | National Reloading Manufacturers' Association | |||||||||
NSSF | > | National Shooting Sports Foundation | |||||||||
SAAMI | > | Small Arms and Ammunition Manufacturers Institute | |||||||||
SASS | > | Single Action Shooters Society | |||||||||
USPSA | > | United States Practical Shooting Association |
Muzzle Energy | Momentum In Pound Seconds | ||||||||||||||
Weight of bullet (in grains) x velocity (in foot seconds) x velocity x 0.000002218 = energy in foot pounds. | * | Multiply the bullet weight in grains by the velocity at impact. Divide the product by 226,000 ( a gravimetric Constant). | |||||||||||||
Example: 100 grain bullet at 3000 ft/seconds > 100 x 3000 x | |||||||||||||||
3000 x 0.000002218 = 1996 foot pounds energy. | * | Example: 45 caliber 240 grain bullet 200 yard velocity of 985 fps. 240 x 985 = 236400 divided by 226,000 = 1.046 pound-seconds momentum. | |||||||||||||
|
|||||||||||||||
Standard Deviation | Coefficient of Variation | ||||||||||||||
Example: 5 shot string, velocity's of 1020, 980, 1000, 1015, 985. First, add the five velocity's and take their average: 1020, 980, 1000, 1015, 985 | * | The coefficient of Variation shows the standard deviation as a percent of the average and is a more reliable measure of a loads consistency. | |||||||||||||
The five velocity's add up to 5000 fps. Their average is 1,000 fps (5000/5) Next subtract the average from each velocity and square the difference. Add up the squared differences (1250) and divide by 4 (the number of velocity's minus one). | * |
The smaller the CV the less variation there is "relative to the average". Divide the average into the standard deviation and multiply the result by 100. From the above example of standard deviation: The S.D. is 17.68. The average is 1000. |
|||||||||||||
Always divide the number of measurements minus one. The result is 312.5 or 17.68: (17.68 x 17.68 = 312.5). | * | Example: 17.68 (SD) divided by 1000 (velocity) = 0.01768 x 100 = 1.768. The CV is 1.768. | |||||||||||||
|
|||||||||||||||
|
|||||||||||||||
|
|||||||||||||||