The 243 Winchester does two jobs well. With light bullets it is a fast, flat varmint rifle. With heavier bullets it is a mild-kicking deer rifle that young hunters can handle. That split shows up in 243 ballistics: the light loads and the deer loads look like they come from two different cartridges. Here are the published numbers for both, and how to choose between them.
What Caliber Is a 243?
The 243 fires a 6mm bullet that measures .243 inch. Winchester introduced it in 1955 by necking the 308 Winchester case down to 6mm. That means it fits a short action, and many 308-size rifles come in 243 too.
Don’t mix it up with the 6mm Creedmoor or the 6mm Remington. All three fire the same bullet diameter, but the cases are different. Use only the round stamped on your barrel.
Varmint Loads: 55 to 75 Grains
Light bullets give the 243 its speed. They suit prairie dogs, groundhogs, coyotes and foxes. Thin jackets and polymer tips open fast and help limit ricochet.
| Load | Bullet | Grain | Muzzle velocity (fps) | Muzzle energy (ft-lbs) | Pack |
|---|---|---|---|---|---|
| Buffalo Bore 243 55 Grain Ballistic Tip Supercharged Varmint | Nosler Ballistic Tip (polymer tip) | 55 | 4,100 | 2,053 | 20-round box |
| Hornady Superformance Varmint 243 58 Grain V-Max | Hornady V-Max polymer tip | 58 | 3,925 | 1,984 | 20-round box |
| Nosler Varmageddon 243 55 Grain Polymer Tip | Nosler Varmageddon Polymer Tip | 55 | 3,800 | 1,763 | 20-round box |
| Winchester Varmint 243 65 Grain Extreme Point | Polymer Tip (Winchester Extreme Point) | 65 | 3,620 | 1,891 | 20-round box |
| Hornady Superformance Varmint 243 75 Grain V-Max | Hornady V-Max polymer tip | 75 | 3,580 | 2,134 | 20-round box |
| Nosler Ballistic Tip Varmint 243 70 Grain | Nosler Ballistic Tip Polymer Tip | 70 | 3,500 | 1,904 | 20-round box |
| Federal Varmint and Predator 243 75 Grain JHP | Jacketed Hollow Point | 75 | 3,375 | 1,897 | 40-round box |
| Browning BXV Varmint 243 65 Grain Polymer Tip | Browning Rapid Expansion Matrix Tip (BXR) Polymer Tip | 65 | 3,400 | 1,668 | 20-round box |
The Buffalo Bore 55 grain Ballistic Tip Supercharged Varmint lists 4,100 fps and 2,053 ft-lbs. The Hornady Superformance Varmint 58 grain V-Max lists 3,925 fps and 1,984 ft-lbs. Note that these bullets are built to break up. They are not deer bullets.
Deer Loads: 80 to 100 Grains
For deer and pronghorn, use bullets built to hold together and penetrate. Most deer loads weigh 85 to 100 grains.
| Load | Bullet | Grain | Muzzle velocity (fps) | Muzzle energy (ft-lbs) | Pack |
|---|---|---|---|---|---|
| Hornady Custom Lite 243 87 Grain SST Reduced Recoil | Hornady SST (Super Shock Tip) Polymer Tip | 87 | 2,800 | 1,514 | 20-round box |
| Barnes VOR-TX 243 80 Grain TTSX Lead-Free | Barnes Tipped TSX polymer tip | 80 | 3,350 | 1,994 | 20-round box |
| Federal Barnes TSX 243 85 Grain Lead-Free | Barnes TSX hollow point | 85 | 3,200 | 1,933 | 20-round box |
| Hornady Precision Hunter 243 90 Grain ELD-X | Hornady ELD-X polymer tip | 90 | 3,150 | 1,983 | 20-round box |
| Hornady Superformance 243 95 Grain SST | Hornady SST (Super Shock Tip) polymer tip | 95 | 3,185 | 2,139 | 20-round box |
| Remington Core-Lokt Tipped 243 95 Grain | Polymer tip (Core-Lokt Tipped) | 95 | 3,140 | 2,080 | 20-round box |
| Nosler AccuBond 243 90 Grain Trophy Grade | Nosler AccuBond bonded polymer tip | 90 | 3,100 | 1,920 | 20-round box |
| Remington Core-Lokt 243 100 Grain Soft Point | Jacketed soft point (Core-Lokt) | 100 | 2,960 | 1,945 | 20-round box |
| Norma American PH 243 100 Grain Oryx Bonded Soft Point | Norma Oryx Jacketed Soft Point (bonded) | 100 | 2,990 | 1,986 | 20-round box |
| Buffalo Bore 243 100 Grain Partition Supercharged | Nosler Partition spitzer soft point | 100 | 3,150 | 2,203 | 20-round box |
The Remington Core-Lokt 100 grain soft point lists 2,960 fps and 1,945 ft-lbs. The copper Barnes VOR-TX 80 grain TTSX lists 3,350 fps and 1,994 ft-lbs. Copper bullets keep most of their weight, so a lighter one can still penetrate well.
How to Read 243 Ballistics
Muzzle velocity is the bullet’s speed at the barrel, in feet per second. Muzzle energy is its punch in foot-pounds. Energy rises with the square of speed, so fast light bullets post strong energy numbers.
Look at two loads with near-equal energy. The Nosler Varmageddon 55 grain lists 3,800 fps and 1,763 ft-lbs. The Core-Lokt 100 grain lists 2,960 fps and 1,945 ft-lbs. The energy is close, but the result on game is not. The varmint bullet blows up near the surface. The deer bullet goes deep. That is why bullet type matters as much as the numbers.
Barrel, weather, altitude and 243 ballistics
Factory figures come from test barrels, often 24 inches long. Many 243 rifles have 20 or 22-inch barrels and will run slower. Cold temperatures slow powder burn. High altitude lowers drag. If you want real 243 ballistics for your gun, chronograph your own rifle and ammo.
Is a 243 a Good Deer Rifle?
Yes, within reason. With a good 90 to 100-grain bullet, a 243 handles whitetail and pronghorn at normal hunting ranges. Shot placement matters more with a smaller bullet. Pass on poor angles and keep shots inside the range you have practiced.
Good picks include the Nosler AccuBond 90 grain, which lists 3,100 fps and 1,920 ft-lbs, and the Norma American PH 100 grain Oryx, which lists 2,990 fps and 1,986 ft-lbs. Both use bonded cores that hold together.
For new shooters, the Hornady Custom Lite 87 grain SST lists 2,800 fps and 1,514 ft-lbs. It kicks even less than a full-power load.
Some states set a minimum caliber or energy for deer. Laws vary, so check your state’s hunting rules before you choose a load.
243 vs 6mm Creedmoor
Both fire 6mm bullets from a short action. The 6mm Creedmoor is newer and favors long, heavy match bullets. The 243 has a deeper lineup of hunting and varmint loads. See our 6mm Creedmoor ballistic data guide to compare. If you shoot a 308 as well, the 308 Winchester ballistics guide covers the parent case.
Shop 243 Ammo
Find varmint, deer and copper loads in our 243 ammo category. Each product page lists the maker’s published specs.
Frequently Asked Questions
Is a 243 a good deer rifle?
Yes, with the right bullet. A 90 to 100-grain bonded or copper bullet handles whitetail and pronghorn at normal ranges. Shot placement matters more than with bigger rounds, so pick good angles. Check your state’s rules, since some set minimum calibers for deer.
What caliber is a 243?
The 243 Winchester fires a 6mm bullet that measures .243 inch. It is a 308 Winchester case necked down to 6mm, introduced in 1955. It fits short-action rifles. The 6mm Creedmoor and 6mm Remington share its bullet size but use different cases.
Is 243 good for deer hunting?
It is a common choice for deer, especially for youth and recoil-shy hunters. Use bullets built for game, such as the Remington Core-Lokt 100 grain, which lists 2,960 fps. Avoid thin varmint bullets on deer. Follow your state’s hunting rules.
What grain bullet is best for a 243?
Use 55 to 75 grains for varmints and predators. Published 243 ballistics are only part of the choice. Use 85 to 100 grains for deer and pronghorn, with a bonded, partitioned or copper bullet. Reduced-recoil loads around 87 grains help new shooters. Your rifle’s twist rate may favor some weights over others.
