The AR- 15 is not just America’s favorite rifle, but America’s favorite hunting rifle as well. The new .350 Legend cartridge is a purpose-built mid- range hunting round made for the AR- 15. Rock River’s CAR A4 in .350 Legend is a great choice for those states which restrict hunting to straight- wall cartridges. (Photo Provided by Author)
February 26, 2025
By James Tarr
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ARs are not just the most popular type of rifle in American, they are the most popular type of hunting rifle in America. While the vast majority of AR-15s are of course chambered in .223 Remington, that caliber is not legal for use on medium and large game in most jurisdictions. But there are all sorts of AR caliber options on the market, and one of the newest, one specifically intended for hunting, is the .350 Legend. Many firearm manufacturers already have .350-chambered rifles in their lineup, and I’m going to take a look at the .350 Legend CAR A4 in Rock River Arms’ LAR-15M line.
For testing Tarr equipped the RRA CAR A4 in .350 Legend with the new Vortex Crossfire II 3- 9X scope with a BDC reticle specifically made for straight- wall cartridges. This budget- priced scope is a great choice for hunting in the areas where the .350 Legend is used. (Photo Provided by Author) This rifle sports the AR-15s two most popular features — a 16-inch barrel and a six-position collapsible stock. Rock River Arms actually offers two versions of this rifle, identical but for the barrel steel. The other model sports a chrome-moly barrel with a black finish. The model tested here has a stainless-steel tube in the white. Both barrels have a 1/16-inch twist.
Rock River Arms knows how to make great barrels, and their stainless barrels are some of the best in the industry. This barrel profile almost looks like a heavyweight, but you have to remember there is a .35 bore down the center of it. As a result, total empty weight of this rifle is 6.8 pounds. Once you add a scope, that means it will be hefty enough to be steady during field-supported shots, but not so heavy you’ll dread carrying in the wild.
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For some reason they’ve tipped this barrel with their Operator muzzle brake (mounted on 1/2"x36 threads). Yes, this brake does reduce recoil, but it also makes the rifle much louder. Unfortunately, many hunters don’t wear ear protection in the field, and as most whitetail encounters don’t require a high volume of fire I think either a plain muzzle or a simple flash hider would be a better choice. And the muzzle brake negates one advantage the .350 Legend has over the .223 Rem and other AR cartridges — it is quieter. Because of that big bore volume, all of the gunpowder has burned up inside before the bullet has left the barrel, making it less harsh on the ears. Everyone should be wearing earpro when hunting (electronic muffs will make sure you don’t miss anything) but, again, many won’t. Quieter guns, suppressed or not, save ears. I think RRA chose this muzzle device simply because it looks cool, but it doesn’t go with the intended purpose of the rifle.
The Rock River Arms CAR A4 uses the traditional AR direct gas blowback action. As a cartridge, the .350 Legend is still in its infancy, being introduced in 2019, so some firearms manufacturers are still doing things a little differently. What do I mean? The .350 Legend is loaded to the same pressure as the .223 Remington but has more than twice the bore volume and is throwing a much heavier bullet significantly more slowly, so the pressure curve is markedly different. Ruger’s .350 Legend-chambered AR sports a short, almost pistol-length gas system, whereas this Rock River uses a traditional carbine length gas system. The low-profile gas block on the RRA has a set screw at the bottom to keep it in place.
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Rock River’s CAR A4 is a full- featured AR- 15 pattern, with a forward assist, brass deflector, ejection port cover, and G.I.- style controls. The trigger guard is oversize for better use with gloves, a smart idea in a gun meant for hunting in the Midwest. (Photo Provided by Author) The beautiful stainless barrel free floats inside a 13-inch aluminum handguard of Rock River Arms’ own design. This lightweight handguard has a full-length MIL STD 1913 “picatinny” top rail and M-LOK accessory attachment slots at 3, 6, and 9 o’clock. The rail slots in the upper receiver are T-marked, but the ones in the handguard are not. T-marked rail slots are a military thing — they help you keep track of where your optics/accessories are mounted, so if you have to remove them you can put them back in the same spot.
The upper and lower receivers are standard forged designs, with all the traditional AR features — brass deflector, forward assist, charging handle, and ejection port cover. Etched in white on the upper receiver above the ejection port you’ll see .350 LEGEND, which I think is a good idea. Caliber is also marked on the top of the barrel, just underneath the handguard, along with the barrel twist, but the receiver marking is far easier to see.
The selector, magazine release, and bolt catch are straight G.I. in design. The rifle uses RRA’s oversize Winter Trigger Guard, which I think is a smart move in a rifle intended for hunting. Deer season in Michigan is often very cold, and gloves are a must. The pistol grip has the same profile as the military A2, but instead of hard polymer it is made of rubber for a little extra grippiness.
(top left) To test the rifle Tarr used Vortex’s new Crossfire II scope with straight- wall BDC reticle. Tarr used a QD Midwest Industries mount which worked great with the scope’s generous eye relief. (top right) Rock River’s .350 Legend CAR A4 uses a carbine-length gas system, unlike other rifles on the market. Even with the big 50mm objective lens, mounting the Vortex Crossfire II scope at a standard height provides plenty of clearance over the rail. (bottom left) The rifle comes standard with Rock River Arms’ Operator muzzle brake. (bottom right) The .350 Legend cartridge requires specific magazines and a 10- round steel DuraMag provided with the rifle.(Photo Provided by Author) Rock River Arms’ two-stage match trigger has been well-known and respected for several decades, and that’s what you’ll find in this rifle. It has a short take up, and then a very crisp break. Trigger pull weight on this sample was 4.5-pounds. This rifle uses a standard carbine buffer and spring. The gas key on the bolt carrier has been properly staked, and the interior of the bolt carrier is chrome lined.
The buttstock is RRA’s Operator CAR stock. It has a rubber buttpad and sports several different options for mounting slings. Push the small button on the left side of the buttpad and you can slide it down, revealing two cylindrical compartments sized just right for storing AA and CR123 batteries for optics or lights. The compartments have an O-ring sealed cap which at least makes them water resistant. The stock rides on a standard six-position buffer tube.
This rifle is supplied with RRA’s two- stage match trigger, which has been highly regarded for decades. It provided a crisp 4.5- lb pull, perfect to allow precise shots when hunting. All the controls — bolt catch, selector, magazine release — are standard G.I. (Photo Provided by Author) This rifle is intended for hunting, so in addition to the .350 Legend chambering, it is supplied with a short magazine. The website states this rifle is supplied with a ten-round magazine, and my sample was shipped with a short blackened stainless steel magazine made by DuraMag, with a bright orange non-tilt polymer follower marked “350.” While the 350 Legend is the same overall length as the .223 and has the same size case head (so you can use the same bolt) it doesn’t feed properly from standard AR magazines, as they’re meant to work with tapered cases with shoulders.
.350 Legend-specific magazines have much shallower ribs at the front to allow for the wider straight-wall cartridge bodies. .350 Legend cartridges have nearly no body taper, unlike the .223/5.56, so they don’t stack right in the curved 30-round AR magazines. That’s why you won’t find .350 Legend magazines with capacities higher than twenty.
When Michigan, and then other states, allowed the use of straight- wall cartridges for hunting, if you wanted to use an AR your only choice was the .450 Bushmaster (right). It’s really more than you need, and offering a cartridge more suitable for deer led Winchester to develop the .350 Legend (left). (Photo Provided by Author) So why did Winchester introduce a new old-fashioned straight-wall cartridge in the modern era? Well, first, why not? ‘Merica! But second, because of the relaxation of hunting prohibitions in certain states. There are areas in certain states where, due to population density, the use of rifles is not permitted, or heavily regulated. You either have to use a shotgun with slugs if you want to hunt deer or, in some cases, are restricted to a straight-wall cartridge. My home state, Michigan, a few years back decided to allow the use of straight-wall rifle cartridges in the areas of the state where previously only shotgun hunting was allowed, and several midwestern states followed suit.
If you wanted to do your hunting with an AR-15, previous to this your only straight-wall cartridge choice was the .450 Bushmaster, which sends a 250-grain bullet downrange at 2,200 fps or so. So, the sales of .450 BM ARs soared, but that cartridge is a bit of overkill for deer, and provides more recoil than some shooters are interested in. With the .350 Legend, Winchester has provided a lighter-recoiling option that is ideal for deer-sized game. In fact, the ballistics of the .350 Legend are very similar to the .30-30, which for several generations (in lever action rifles) was considered the quintessential deer cartridge.
Tarr was immediately reminded of the .30 Carbine round (left) when first seeing the .350 Legend. In looks and performance it is basically a “.35 Carbine,” closely resembling the performance of the famous .30- 30, except designed for the AR- 15 platform. (Photo Provided by Author) That means that it is a short- to medium-range cartridge, and I wouldn’t recommend it being used much beyond 200 yards, but you rarely find shots even that long in the states (like Michigan and Ohio) where straight-wall cartridges are likely to be used. I’m old enough to have actually hunted deer with a .30-30 lever action (a Winchester ’94 with a Williams ghost ring rear sight). This was in the woods of western Michigan, and my longest shot was fifty yards — perfect for the .30-30, and perfect for the .350 Legend.
Winchester also did things smart, and economically. Cartridge cases are formed from brass discs that are then worked into shape. The brass disc that forms the .350 Legend case is the same one that forms the .223 Remington case, except it requires less work. You know what a .223 Rem case looks like halfway through the forming process? A .350 Legend case. They share case head dimensions, and have nearly the same overall length. As for the .350 Legend bullets, a lot of the tooling is the same as what is used to produce 9mm pistol bullets, although the .350 Legend does not use pistol bullets.
.223 and 9mm are the two most popular cartridges in America, and Winchester designed a cartridge that, at least from a manufacturing standpoint, is a hybrid of the two, allowing for quick and easy production. Because of this, it was easy for other ammunition manufacturers besides Winchester to start producing .350 Legend ammo. Currently, Hornady , Browning, and Federal offer .350 Legend ammo in addition to Winchester. If you’re into handloading, straight wall rifle cartridges are the simplest rifle cartridges to work on, so you’re in luck.
The first time I ever held a .350 Legend cartridge in my hand I was immediately reminded of the .30 Carbine. There’s a photo somewhere around here of the two cartridges together, and you’ll see how similar they are. The Legend has the same proportions as the legendary carbine round, it’s just a little bigger. And if you look at the ballistics you’ll see the .350 Legend is basically a .35 Carbine — the bullet is a little wider and a little heavier, travelling the same or slightly increased speed. The M1 Carbine traditionally throws a .30 110-grain bullet downrange just over 1,900 fps. The .350 Legend ups those numbers just a bit in every direction — a .35 160-grain (or so) bullet at 2,100 fps out of sixteen-inch barrels. More than potent enough for medium game at close to medium ranges.
Rock River’s CAR A4 in .350 Legend is a sub- 1.5 MOA gun with most ammo, but be advised not all .350 Legend ammo is the same. Winchester’s Super Suppressed subsonic load is meant to be quiet through a suppressor, and is very accurate, but it’s far less powerful than standard ammo. (Photo Provided by Author) The rifle does not come with any sights. As a rifle intended for hunting, the folks at Rock River assume buyers will be mounting a scope atop it. For this review, I secured a sample of Vortex Optics’ new Crossfire II riflescope with a BDC reticle optimized for straight wall cartridges. The Crossfire II is one of Vortex’s economically-priced scopes. This 3−9X variable magnification scope has a one-inch main tube and a 50mm objective lens. The capped turrets are click adjustable (by hand), with each click 1/4 MOA. Suggested MSRP is $209, which means you might see it for sale under $200.
The 3−9X for decades was the most popular variable magnification range in America. I don’t know if it still is, but that range is ideal for any kind of hunting you’d be using this rifle/cartridge for. At its lowest magnification, 3X, you can quickly get on targets as close as fifty feet, and 9X is enough for you to identify and engage game out to the limits of the .350 Legend.
The reticle is a simple duplex, with several horizontal holdovers beneath it. Vortex provides some holdover information (MOA drop) for those hashmarks for various .450 Bushmaster, .350 Legend, and .45-70 Government loads, but encourages people to go to their website (VortexOptics.com) and use their ballistic calculator to determine the exact drop for the load they are using. As an example, for a 150-grain .350 Legend load with a muzzle velocity of 2,325 fps zeroed at 100 yards here’s some data:
1st hashmark: 1.5 MOA drop, for a 150-yard zero
2nd hashmark: 4.9 MOA drop, for a 230-yard zero
3rd hashmark: 7.6 MOA drop, 280 yards
Top of bottom duplex post: 11.4 MOA, 340 yards
These are sample numbers, but you can see straight wall cartridges are not lasers flying flat out to 300 yards and beyond like some purpose-built western magnums, so knowing your drops at various distances is important.
The M-LOK slots on the handguard will allow you to easily mount a bipod on the rifle if you so choose. At the range I did my accuracy work off a rest, but then did a little bit of shooting from field positions — kneeling, sitting, and standing supported, bracing myself off various things. I posted a reduced whitetail target at 100 yards and took three shots at it from the kneeling supported position … and impressed the hell out of myself by producing a two-inch group. This rifle is more than accurate enough to hit deer where it counts far beyond the practical limit of the cartridge — roughly two hundred yards or so. To get that bullet where it needs to go is up to you.
(Data Provided by Author) To quote the late great Jeff Cooper on hunting, a man who was as much a rifleman as he was a pistolero, “If you can get closer, get closer; if you can get steadier, get steadier.” Which is why he was an avid proponent of the rifle sling, it allows you to get steadier even if there’s nothing around to lean on. I’ve used this mantra while running a rifle at a 3-gun match, and it’s even more important while hunting. Do whatever you can to guarantee you make that first shot, because you probably won’t get a second.
Recoil, to a great degree, is a math problem. If you compare the numbers of the .350 Legend to the .223 Remington (bullet weight and velocity), whether you use practical shooting’s Power Factor formula or do the calculations for foot-pounds of energy, the .350 Legend is a more powerful round, and you’ll feel that when shooting. With the standard loads, felt recoil is 30−50% more than the .223, which means it still isn’t much. Nothing like a .300 WinMag in an ultra-light bolt action, that’s for sure. The subsonic Winchester ammo was an absolute pussycat, but then again it basically reproduces the ballistics of a pistol caliber carbine.
Firearms News editor Vincent DeNiro took the Rock River Arms’ LAR-15M out into Ohio’s woods for a couple of days during the 2020 deer season. (Photo Provided by Author) Having America’s favorite hunting rifle chambered in a cartridge which basically replicates the ballistics of America’s favorite deer cartridge (the .30-30) seems like a smart move, and both the .350 Legend and Rock River Arms’ LAR-15M CAR A4 deliver on their promises.
