Nitrex TR one 6-20x50mm AO Riflescope

By the Guns and Shooting Online Staff

Nitrex 6-20x50mm AO Riflescope
Illustration courtesy of Nitrex Optics.

Nitrex is a new brand of riflescope made in Japan for ATK. ATK is a world leader in weapons technology that also owns Federal, Speer, CCI, Estate Cartridge, Alliant Powder, RCBS, Outers and several other well known companies. At one time, ATK also owned Weaver, Redfield and Simmons, but sold those scopes and optics brands to Meade Optical Co. (ATK retained the Weaver, Redfield and Simmons scope mount lines, however.) Now, ATK is back in the riflescope business with the premium Nitrex line.

The initial Nitrex scope offerings are the TR-one series. These scopes are made in Japan. ATK states that every Nitrex scope is subjected to some of the most rigorous testing in the industry: "We heat it, freeze it, thump it, bump it, and submerge it´┐Żall in the quest to replicate the harshest hunting conditions. These steps are taken because we know hunters demand tough and rugged optics for their firearm." All Nitrex scopes carry a Limited Lifetime Repair Warranty with a one year, over-the-counter direct exchange policy applicable to the original purchaser.

The initial Nitrex line includes 1.5-5x32mm, 3-9x42mm, 3-10x50mm and 6-20x50mm AO models. It is the matte black version of the latter that is the subject of this review. (The 6-20x50mm AO is also available with a silver finish.)

This 6-20x50mm Nitrex is physically large, although not particularly heavy, with a one-piece main tube machined from aircraft quality aluminum alloy, fully multi-coated lenses with extra hard-coated exterior surfaces, adjustable parallax correction (25 yards to infinity), rubber covered Euro-style fast focus eyepiece ring and a very fine Trex-Plex (Duplex-type) reticle. The scope is purged and nitrogen filled; it is claimed to be waterproof, fogproof and shockproof. The knurled aluminum zoom ring has a squared-off, tactile bump and turns easily, but not too easily. Lens caps, unfortunately, are not supplied. The front objective bell is threaded to accept a three inch sunshade, which is available at extra cost.

Like all TR-one scopes, the big 6-20x50mm AO features Trex three-point precision windage and elevation adjustments. The Trex three-point precision system uses triangulated contact points for precise and repeatable adjustments that eliminate drift and maintain zero. The fingertip adjustable target knobs on the 6-20x50mm AO click in 1/8 MOA increments.

Here are some basic specifications for our Nitrex TR-one 6-20x50mm AO riflescope.

  • Model number: 94580
  • Finish: Matte black
  • Eye relief: 3-1/4"
  • Field of view at 100 yards: 18' (6x); 6' (20x)
  • Length: 16-1/8"
  • 2008 MSRP: $419.99

In order to get some range time with this new Nitrex TR-one scope, we mounted it on a Savage Model 12 Varminter Thumbhole rifle that we were reviewing (see the Product Review Page for this rifle review) in high Millett rings on Weaver two-piece bases. Guns and Shooting Online staff members Jack Seeling, Bob Fleck, Rocky Hays and Chuck Hawks participated in this part of the Nitrex evaluation. Mounting was straightforward and no difficulties were encountered. The big Savage rifle and the big Nitrex scope made an impressive and formidable combination.

After preliminary bore sighting, it took exactly two shots to put the second bullet in the "X" ring of our 25 yard target. The scope's AO feature is a definite asset at short, as well as long, range. We then moved back to 100 yards to zero-in our test rifle/scope at an indicated 16x and do some serious shooting. We found the range markings on the adjustable objective to be right on the money. The accurate Target adjustment knobs made zeroing a simple task and the fine Trex-Plex reticle is excellent for target shooting.

The optics provided sharp, contrasty views of the target with practically no discernable falloff at the extreme edges of the field of view. Flare was well suppressed. The scope held its zero across the full range of magnifications. We were impressed by the view through the Nitrex 6-20x50mm AO.

We did feel that the 3.27" eye relief, while adequate for a .223 Varmint rifle, is inadequate for the more powerful big game calibers. This is not too big a flaw, since a 6-20x scope has very little application beyond varmint hunting and target shooting, but if your target rifle is a .30-06 or .300 Magnum, you will probably want to look for a scope with more eye relief. The other drawback is a rather narrow eye box. The scope blacks out rather easily if your eye is misaligned with the optical axis. Again, while this might be a problem on a big game rifle, on a target or varmint rifle it is less important. Optical design is a series of trade-offs and you can't have everything. For its intended purposes, this Nitrex represents a rational series of design compromises.

Interestingly, at the same time we had the Nitrex at the range, we were also reviewing an expensive European made hunting scope that sells for about three times the price of the Nitrex. All of us felt that the Nitrex provided better views of the target when both scopes were set at the same magnification. That is an impressive optical performance!

Everyone who tried this Nitrex 6-20x50m AO riflescope liked it. It provides clear, sharp views of the target and the reticle is ideal for aiming at small, well defined targets at long range. It is powerful competition for scopes in what we like to refer to as the three-star price class, which includes such stalwarts as the Weaver Classic and Bushnell 3200 series scopes.

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