Cartridge Selection in the AR15 and AR10 Platform For Long Range
Posted Sep 2nd, 2018 in Review
Getting ready to order or build a new precision AR? One of the first things you will need to do is select the right platform for your needs. One of the key deciding factors in either an AR15 or AR10 platform will be the cartridge it will shoot. We will review popular cartridge choices in the AR15 and AR10 platforms by running ballistics on popular loads for long range shooting and by using the Applied Ballistics WEZ.
Evaluation Criteria
Using common cartridges for the AR15 and AR10 and running numbers through Applied Ballistics and the WEZ we can analyze and compare bullet drop, wind drift, and hit probability at various ranges. We will review the following cartridges:
- .223 Remington (AR15)
- 6.5 Grendel (AR15)
- 224 Valkyrie (AR15)
- .308 Winchester (AR10)
- 6mm Creedmoor (AR10)
- 6.5 Creedmoor (AR10)
Ballistics Overview
Using the published G7 BC of each bullet we will run the data through Applied Ballistics software to generate data tables on every cartridge/loading. A density altitude of 2 feet (the default setting on AB Analytics software) and a full value wind of 10 MPH will be used in every scenario. All data is run assuming velocity through an 18″ barrel to keep a constant. Longer barrels will produce higher velocity and generate less drop and wind drift.
.223 Remington (AR15) 18″ barrel shooting 73 gr Berger Match BT Target @ 2700 FPS
6.5 Grendel (AR15) 18″ barrel shooting 123 gr ELD Match @ 2450 FPS
224 Valkyrie (AR15) 18″ barrel shooting 82 gr Berger Match BT Target @ 2880 FPS
.308 Winchester (AR10) 18″ barrel shooting Berger 168 gr Match Hybrid Target @ 2580 FPS
6mm Creedmoor (AR10) 18″ barrel shooting Sierra 110 gr SMK @ 2870 FPS 
6.5 Creedmoor (AR10) 18″ barrel shooting Berger 130 gr AR Hybrid OTM @ 2600 FPS 
Hit Probability
Using the Applied Ballistics WEZ (weapon employment zone) a hit probability simulation can be run on each cartridge/loading. Each Cartridge/loading will be run through the WEZ at the following ranges and target sizes:
- 300 Yards on a 1 MOA circle target (3.141″)
- 500 yards on a 1 MOA circle target (5.230″)
- 700 yards on a 1 MOA circle target (7.329″)
- 900 yards on a 1 MOA circle target (9.423″)
- 1100 yards on a 1 MOA circle target (11.517″)
- 1300 yards on a 1 MOA circle (13.611″)
The Following data will be used for all simulations
- Wind: +/- 1 MPH
- Temperature: +/- 1 degree
- Pressure: +/- .05 inHG
- Humidity: +/- 3%
- Muzzle Velocity: +/- 15 FPS
- Range: +/- 1 meter
- Inclination: +/- 1 degree
- Heading: +/- 5 degrees
- Lattitude: +/- .001 degree
- Rifle/ Shooter Proficiency: 1 MOA
300 Yard Target
.223 Remington
6.5 Grendel
224 Valkyrie
.308 Winchester
6mm Creedmoor
6.5 Creedmoor
500 Yard Target
.223 Remington
6.5 Grendel
224 Valkyrie
.308 Winchester
6mm Creedmoor
6.5 Creedmoor
700 Yard Target
.223 Remington
6.5 Grendel
224 Valkyrie
.308 Winchester
6mm Creedmoor
6.5 Creedmoor
900 Yard Target
.223 Remington
6.5 Grendel
224 Valkyrie
.308 Winchester
6mm Creedmoor
6.5 Creedmoor
1100 Yard Target
.223 Remington
6.5 Grendel
224 Valkyrie
.308 Winchester
6mm Creedmoor
6.5 Creedmoor
1300 Yard Target
.223 Remington
6.5 Grendel
224 Valkyrie
.308 Winchester
6mm Creedmoor
6.5 Creedmoor
Overview
Looking at the data generated on the ballistic tables and WEZ hit probability simulations should help make a decision about what cartridge and then what platform will work best for you. The range in which you intend to shoot and the performance of the bullet against wind are large factors to consider when choosing a cartridge for long range shooting. Keep in mind longer barrels will produce more velocity and more velocity will decrease drop and wind drift and increase your hit probability.