The 400 legend vs 350 legend question comes up every fall among hunters who live in straight-wall states or simply want a hard-hitting, short-range deer rifle. Both cartridges come from Winchester, both fit the AR-15 platform, and both were designed with state straight-wall rules in mind.
They are not interchangeable, though. The 400 Legend pushes a heavier, wider bullet, while the 350 Legend offers a lighter-recoiling package with a wider choice of ammunition and parts. Our editors break down the published specs, what they mean in the deer woods, and how each one changes the upper you build or buy. Check your state regulations before you commit to either.
Want to see what a ready-to-run straight-wall upper looks like? Browse our complete upper coverage.
Key Takeaways
- Winchester introduced the 350 Legend first and followed it with the 400 Legend at the 2023 SHOT Show.
- The 400 Legend fires a 215 grain bullet of about .40 caliber, while common 350 Legend loads use .357 inch bullets in the 145 to 180 grain range.
- Winchester's published Power-Point figures put the 400 Legend at noticeably higher muzzle energy than the 350 Legend.
- The two cartridges use different case head sizes, so they need different bolts and different magazines in an AR-15.
- Both are short-to-moderate range deer cartridges, and Winchester describes the 400 Legend as best suited to shots inside 300 yards.
Where the Two Legend Cartridges Came From
Several states limit deer hunters to straight-walled rifle cartridges with rules on bullet diameter and case length. Winchester built the 350 Legend to fit those rules while still working in a standard-length AR-15 magazine well. It caught on quickly with hunters and with rifle makers.
The 350 Legend
According to Winchester, the 350 Legend uses a .357 inch bullet in a 1.71 inch case with an overall cartridge length of 2.26 inches. That length lets it run in AR-15 receivers and many compact bolt actions. Winchester also notes that it does not run in standard 223 Remington or 5.56mm magazines and needs its own magazine.
The 400 Legend
The 400 Legend arrived at the 2023 SHOT Show as a bigger-bore take on the same idea. American Hunter reports a .4005 inch bullet, a 1.65 inch case and a 2.26 inch maximum overall length. The shorter case was chosen to stay under case-length limits some states impose. Like the 350 Legend, it headspaces off the case mouth.
Specs Side by Side
Numbers do not kill deer on their own, but they explain why these cartridges behave differently. The table below uses Winchester's published data and SAAMI figures summarized by The Ballistic Assistant.
| Spec | 350 Legend | 400 Legend |
|---|---|---|
| Bullet diameter | .357 inch | .4005 inch |
| Case length | 1.71 inches | 1.65 inches |
| Max overall length | 2.26 inches | 2.26 inches |
| Case head diameter | .378 inch | .422 inch |
| Winchester Power-Point load | 180 grain at 2,100 fps | 215 grain at 2,250 fps |
| Published muzzle energy | 1,762 ft-lb | about 2,400 ft-lb |
What the Energy Gap Means
Winchester markets the 400 Legend as delivering energy equivalent to the 450 Bushmaster with less recoil. On paper it carries several hundred more foot-pounds at the muzzle than the 180 grain 350 Legend Power-Point. For deer, that extra margin mostly shows up as a bigger, heavier bullet that tends to penetrate deeply.
Pressure and Velocity
The 350 Legend runs at a higher rated pressure, which helps lighter bullets reach their speeds. The 400 Legend runs at lower pressure and relies on a larger bore and heavier bullet. Real velocities depend on your barrel length and the specific load, so always chronograph your own rifle if exact numbers matter.
Curious how the 350 Legend stacks up against a lever-action favorite? Read our matchup.
400 Legend vs 350 Legend in the Deer Woods
Most whitetails are taken at modest distances, which is exactly where both cartridges are designed to work. The choice usually comes down to how much bullet you want, how much recoil you tolerate and how far your typical shot is.
Terminal Performance
A 215 grain, roughly .40 caliber bullet makes a larger initial hole than a .357 inch bullet. Hunters who sit over thick cover or hunt large-bodied deer often like that extra frontal area. A well-placed 350 Legend bullet is still widely used for deer, and shot placement matters far more than which Legend you pick.
Effective Range
Winchester describes the 400 Legend as a strong choice for hunting situations within 300 yards. Both cartridges use blunt, relatively slow bullets, so drop increases quickly past the mid-range. Zero your rifle, learn your load's drop at the distances you hunt and keep shots inside your proven ability.
Recoil and Follow-Up Shots
Heavier bullets mean more recoil, all else being equal. Winchester claims the 400 Legend recoils less than a 450 Bushmaster and much less than a 12-gauge slug, but expect it to feel stouter than a 350 Legend. If a new or younger hunter will share the rifle, the softer cartridge is often the easier one to shoot well.
How Each Cartridge Changes Your AR-15 Upper
This is where the two Legends differ most for AR builders. You cannot swap a 350 Legend barrel for a 400 Legend barrel and call it done.
Bolt and Bolt Face
The 400 Legend shares its .422 inch case head with the 6.8 SPC, so it needs a bolt with a matching bolt face. The 350 Legend's .378 inch head is much closer to the 223 family. Always use the bolt the barrel maker specifies, confirm headspace, and have a qualified gunsmith check your work if you are unsure. Our headspacing guide explains why that step matters.
Magazines
Each cartridge needs a magazine built or approved for it. For the 350 Legend, start with dedicated 350 Legend magazines. For the 400 Legend, follow the rifle or upper maker's recommendation, since feeding depends on the magazine and the follower.
Barrels and Gas
Straight-wall cartridges often use their own gas port sizing. Leave port work to the barrel manufacturer and never drill or modify a gas port yourself. If you are shopping parts for a 350 Legend build, browse 350 Legend barrels and read our notes on gas system length.
Parts and Ammo Availability
The 350 Legend has been on the market longer, so it generally offers more factory loads and more AR parts. The 400 Legend is newer, and its ammo and parts selection is still narrower. Before you commit, check that you can find hunting ammo locally and that your preferred barrel maker supports it.
What You Can Buy at AR15Parts.com
350 Legend uppers are commonly built on barrels from makers like Wilson Combat and Shaw, often with 16 and 18 inch length options and a range of rail lengths. You can browse 350 Legend uppers to see current options. Complete uppers are assembled in-house, headspaced and function-checked before they ship, and shipping runs 3 to 5 business days. 400 Legend uppers are newer to the market and less widely available, so check current listings before planning a build.
If You Want More Bore
Hunters who want a bigger straight-wall bullet in a parts kit that is easy to source can also look at 450 Bushmaster uppers. It needs its own magazines and bolt setup too, so plan the build as a complete system.
Legal and Safety Notes
Straight-wall rules differ by state and can change between seasons. Some states set limits on bullet diameter, case length or both. Confirm the current rules with your state wildlife agency before you buy a rifle or ammunition for deer season.
Barrel Length and the NFA
A barrel under 16 inches on a rifle, or an overall length under 26 inches, makes a short-barreled rifle under federal law. Since January 1, 2026 the federal SBR tax is $0, but ATF registration is still required. See the ATF's NFA page and remember that state and local laws vary.
Safe Handling
Always work on an unloaded firearm and follow each manufacturer's instructions. Never chamber a cartridge in a barrel not marked for it. The two Legends look similar in a pocket, so keep ammo boxes clearly separated if you own both.
Which Legend Should You Pick
For the 400 legend vs 350 legend decision, think about your deer, your distances and your shooters. Pick the 400 Legend if you want maximum bullet weight in a straight-wall AR and do not mind more recoil. Pick the 350 Legend if you value lighter recoil, broader ammo choice and easier parts sourcing.
Quick Decision Points
- Large-bodied deer in thick cover: the 400 Legend's heavier bullet is appealing.
- Recoil-sensitive or new hunters: the 350 Legend is usually easier to shoot well.
- Ready-made AR uppers and parts: the 350 Legend currently has wider support.
- Already own 6.8 SPC parts: a 400 Legend build may reuse some bolt-face knowledge, but confirm compatibility with the maker.
Still weighing other cartridges? Our deer caliber roundup covers the wider field.
