AR-15 Rifles NEMO Omen .300 Win. Mag. Review Patrick Sweeney August 19th, 2013 | More From Patrick Sweeney Share0 Tweet Email In the 1980s, I was delving deep into all things AR. I was shooting them in the first 3-Gun matches, building them up and repairing the home-built Frankenguns my customers would bring in. I was also experimenting. I had worked out a number of caliber conversions for the AR and even considered what it would take to turn the early AR-10, a fragile and rare rifle, into a reliable one. Never in my wildest dreams did I think to build one in .300 Winchester Magnum. All that passed through my mind when the guys at NEMO handed me their Recon rifle at one of our company’s editorial Roundtables. Hmm, some could say it is a tad portly, but then again, who wants an airweight .300 Win. Mag.? The controls were in the right places, and I liked the fact that NEMO was handing me one that had the camo finish all scuffed and worn. Clearly, this was no toolroom R&D orchid, but a working rifle that was expected to get shot hard and hung up wet. And it had a muzzlebrake on it. Again, I would consider a brake on anything chambered in .300 Mag. to be de rigeur. “The muzzlebrake is our own design, and it really decreases recoil,” says NEMO. I looked at the brake and the roof over our heads. I stepped forward as I shouldered the rifle to make sure I had the brake out past the eaves and, planting the crosshairs on a plate, touched it off. Not bad at all. I turned to the NEMO guys and asked, “How soon can you send me one?” If I said the Recon they sent me was very interesting, you’d think I was bored. No, it intrigued me in a way I haven’t felt in a long time. The controls and the parts you hold on to are all bog-standard AR-type parts, or sized as .223/5.56 parts. The stock is a Magpul STR on a Mil-Spec tube (with a properly staked castle nut), so if you don’t like the stock, you can change it. The pistol grip is a Hogue; ditto on changing it. The safety and trigger are right where you’d expect them to be, and the handguard is refreshingly slim, especially for a rifle chambered in .300 Win. Mag. The forearm on the Recon is particularly slim, as it is octagonal and no larger than it needs to be. While it has a rail along the full length of the top, the sides are bare save for threaded screw holes. Want a section of rail for a light, laser or bipod? Bolt one on. The rest stays bare and slim. The rifle came with two short sections of rail on it, so there would be a chance to attach a bipod or illumination tool if I so desired. The forearm free-floats the barrel, plus it is anchored to the upper receiver. Not only does it clamp on the barrel nut, the forearm has two anchor screws, 90 degrees to one another, fastening the handguard to the upper receiver. The really interesting parts are the middle and the muzzle. The receivers are large. No, I mean large. The upper has a Picatinny rail along its length, flush and even with the rail on the handguard. You could bolt more gear up there than you could pick up, so show some restraint. The lower has a magazine well proportioned to accept the proprietary .300 Win. Mag.-size magazines, and the edges of it are scaled up as well. It is big, but you don’t get the impression that this is an anvil, it’s just really muscular. The bolt and carrier are obviously scaled up from even a .308 rifle, and the nickel-boron-coated carrier has an interesting detail: The charging handle is attached directly to the carrier — no top-center charging handle flimsily fabricated from aluminum. Instead there’s a hefty handle to hang on to. Plus, the billet-cut receivers are done in NEMO’s Tango pattern, a brushed-stripe, black-and-bronze-camo anodized, not painted, finish. Inside the lower we have a Geissele two-stage trigger. The gas port is covered by a low-profile gas block that has an adjustable gas-flow knob on its front face. Out in front of that is the muzzlebrake, a multiport one clearly designed to take the steam out of recoil. A long-range rifle needs suitable optics, and I had just the hunk of glass on hand to fit: a Nightforce 5-25x56mm ATACR and their MIL-R reticle, complete with a selection of Nightforce rings to choose from. The 5-25X is an impressive assembly of optical engineering, but to get the kind of performance it delivers, you pay for it. Not just in cost, although I find I have to keep telling the little voice in my head that I’m not paying for this gear in 1982 dollars anymore. After buying proper, professional lenses for my DSLR camera, I’m not as startled at the price for good firearms optics. No, the big price is in weight. Glass weighs a lot. In fact, glass can be three to seven times as dense as water, with optical glass not being near the bottom of that scale. The Nightforce ultralight rings use hefty bolts to clamp down on the Picatinny rail, and the nuts on them require a half-inch open-end wrench or socket wrench to tighten. You want them tight, but you don’t want to be crushing your receiver, tightening your scope rings with power. GALLERY: NEMO Omen Review 1 of 10 <h2></h2>While the NEMO Omen Recon has a hefty receiver set, the controls are normal-size and located where you expect them to be. Plato: “Only the dead have seen the end of war.” <h2></h2>While the NEMO Omen Recon has a hefty receiver set, the controls are normal-size and located where you expect them to be. Plato: “Only the dead have seen the end of war.” <h2></h2>The NEMO forearm is bolted securely to the receiver, free-floating the barrel. The forearm gives you the option of how many rail mounts you’ll use and where they’ll be, as well as mounting holes for the sections of rail you want. The NEMO Omen models do not use a typical charging handle. The handle is secured directly to the bolt carrier instead. <h2></h2>The carrier’s buffer takes the last bit of recoil out of the carrier as it bottoms out in the extension tube. <h2></h2>Yes, the muzzlebrake is effective. The NEMO 10-port muzzlebrake does a very good job of taking the felt recoil out of the .300 Win. Mag. The pinned-on gas block has an adjustment knob so you can dial back the gas flow for use with suppressors. <h2></h2>Hornady’s new 150-grain SST Custom Lite load minimizes felt recoil and muzzle blast. <h2></h2>NEMO coats both the bolt and its carrier in nickel boron to enhance function. <h2></h2>The NEMO receiver is hefty. It has to be to accept the .300 Win. Mag. magazines. <h2></h2>Shooting the NEMO Recon is work, it just isn’t work to shoot it the way other rifles are work. The rifle, full up, is heavy. That’s the price you pay for soft recoil and the power of .300 Win. Mag. <h2></h2> <h2></h2>Notes: Accuracy results are averages of four five-shot groups at 100 yards off a Sinclair front shooting rest and rear bag. Velocities are averages of 10 shots measured on a PACT MKIV chronograph set 15 feet from the muzzle. Mounting optics such as this to a regular rifle, I’d be just a bit embarrassed. I mean, a 21/2-pound scope, in nuke-proof rings that add more than just a couple of ounces? On a proper-weight M4, that would be a bit silly, but the NEMO Recon tips the scales, absolutely bare, at 10 pounds, 9 ounces. With the Nightforce scope and rings, a sling and a loaded magazine, the Recon comes up to just shy of 15 pounds. Keep in mind, this is a .300 Winchester Magnum, and even with an efficient muzzlebrake, weight is your friend in dealing with recoil. One small problem I had in getting everything at the range to test this rifle was ammo. It’s not that I couldn’t find any, but that I didn’t have any. Once I got home from the InterMedia Roundtable, I checked the ammo shelf. I had one lone box of .300 Win. Mag., a box so old that the price on it was less than $10. I had no memory of how I’d come to acquire it, since I’ve never owned a rifle in this chamber before. I jumped on the phone to beg .300 Win. Mag. ammo from those who have it. Interestingly, a lot of ammo makers list it, but mostly for hunting. In the AR universe, ammo companies have long been hip to where their ammo is used. Everyone who loads .223 has a pretty good idea that it will end up in one of the host of ARs out there on ranges around the country, so they load accordingly. Well, no one who loads .300 has had any idea that there would be an AR-based rifle chambered for it. The most they’d expect is that some hunter with a Browning BAR would use their ammo, and so what? The NEMO engineers had to make their gas system work with the ammo as it existed, not just on specially tuned handloads, thus the adjustable gas-flow knob. The one-dot setting is the suppressor setting, and Gemtech makes a special Sandstorm (titanium) model just for this caliber. Four dots is wide open and more gas than you probably need. The magazines for the Recon are made of polymer, and, as you’d expect from magazines that will accept .300 Win. Mag., they are hefty. If, when I began my AR journey, you had suggested that someone would be offering a fabulously expensive AR and shipping “plastic” magazines with it, I would have laughed. In size, shape and general appearance, they remind me of the magazines for a Dragunov, but even bigger. Until the web-gear guys start making NEMO-specific pouches for us, you may have some trouble packing along extras. At 14 rounds per mag, you are not going to be getting long strings of fire from this, but then that isn’t what it’s for. The basic idea that NEMO has for the Omen line of .300 Winchester Magnum rifles is long-range precision fire to support or replace bigger-than-7.62 bolt-action rifles in the sniper role. This is not the rifle you’d want to be using in an urban slugfest, unless it was all you had. No, the NEMO .300 Omen lineup (the Recon is just the handiest of the models so far) is meant for long-range bad-guy whacking, and you could expand that a bit to close- and medium-range heavy-hitting. After all, a .308 fires a 175-grain match bullet at around 2,600 fps from a 20- or 22-inch barrel. The .300 Win. Mag. promises to best that by 300 fps and with a bullet heavier by 20 grains or more. Higher velocity and better ballistic coefficient means better long-range results. However, with real heavyweights, such as a 200-grain Trophy Bonded Bear Claw, auto glass and other barriers become pretty flimsy protection for would-be miscreants. The handy-length, 18-inch barrel takes a bit of the extra speed away from the big .300, but not much. I started by setting the gas regulator to the low setting and worked my way up. I gauged proper gas settings by how far the brass was hurled. It was easy to set the regulator to keep from trashing brass. At the lowest setting, it flipped the empties about 7 or 8 feet away. At the highest setting, 15, I discovered an interesting problem: The muzzlebrake was too good with some loads. With the low-vigor gas-blasting loads, the muzzle stayed on my mark while I was doing my chronograph work. The heavier-bullet loads had the sights actually pushed down off the target from gas flow through the brake. I could also gauge pretty closely how well I was maintaining my offhand stance; as I got tired, the muzzle started driving off to the right as well as down. You can’t get something for nothing. A muzzlebrake that is that effective is going to blast everything in its path. I tried a few strings from prone, but the autumn litter erupted into clouds of scurrying leaves on each shot. If you are going to be using this for real, you’ll want to have a solution in mind for the muzzlebrake and its effect on your environment. That said, the felt recoil was pretty soft. NEMO also built in a spring-loaded plunger in the rear of the carrier. When the carrier and buffer weight bottom out, the spring-loaded plunger soaks up the last bit of energy, eliminating that bottoming-out bounce that hard-kicking self-loading rifles often have. I don’t like comparing it with other calibers, as we all have our own ideas of what a .243 or a .30-’06 feels like, but the NEMO Recon is a softie to shoot. I did not come away from a range session with a sore shoulder for the price of fun. Shooting the NEMO Recon is work, it just isn’t work to shoot it the way other rifles are work. The rifle, full up, is heavy. That’s the price you pay for soft recoil and the power of .300 Win. Mag. The muzzlebrake is efficient, but you cannot have anything on the firing line with you; it will get blown off. The .300 Win. Mag. is a barrel-heater. Sluicing that much burning powder down the bore on each shot, I found I had to break my bench-testing routine into sets of four five-shot groups and not at anything like a fast pace, then walk down, measure, tape and reset while the barrel cooled. Any faster and the groups opened up. Not a lot, but given the brilliant accuracy of this rifle, you do not want groups opening up. When I kept my cool and the barrel cool, I could punch sub-MOA groups. I had figured that something this radical, this edge-of-the-envelope, would have problems. I expected to see malfunctions, mangled brass, ammo bent and dented by misfeeds. I may as well have saved myself the time spent anticipating problems, for it worked without a flaw. I’m of the opinion that this rifle is a better shooter than I am. I’ve never had the benefit of a rigorous benchrest education, and my bench-and-bag technique is not at as high a level as my high-speed skills are. I was stunned to see quarter-inch groups. I have to give all the credit to the rifle, scope and ammo, as I was pretty much along for the ride. If you have access to a long-distance range, you really ought to give a thought to how you are going to spend your trigger time. Spending it with a NEMO Omen, this Recon or any of the company’s other rifles would not be a bad day. http://brightcove=2616988598001 Look for the NEMO Omen in Book of the AR-15, a publication dedicated to all rifles, optics, and ammunition engineered for the AR-15 platform. Order your copy at the InterMedia Outdoors Store today! Share0 Tweet Email Load Comments ( ) Don’t forget to sign up! Get the Top Stories from Guns & Ammo Delivered to Your Inbox Every Week To sign-up for our newsletter, check this box and submit your email address below. 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