Stryker STR-1
by Bill Mills - Photos by Dawn Mills - May 2008

Features HowItWorks Disassembly Adjustment Testing Data

FEATURES

While a new name on the market, Stryker Paintball comes from a company bearing some of the paintball industry's strongest and longest roots. The Stryker brand is produced and marketed by the Jarden Team Sports congolmerate. Through various mergers and acquisitions, Jarden now includes Brass Eagle, ViewLoader, Worr Game Products, and JT USA among its paintball related divisions. In February of 2008, Jarden formally announced that it was reorganizing its structure to consolidate research and development resources.

The Stryker Paintball brand was born out of consumer focus groups in which discussion panels of potential customers rate the things they find desirable in potential products. Focus group studies were used to identify the name Stryker, the brand identity and even the look of the product line. The marker line is endorsed by Team Dynasty, with Ryan Greenspan appearing in the 30 second Stryker TV commercial, and a Dynasty edition Stryker marker in the 2008 product catalog.

The Stryker STR-1 paintball marker is a stacked tube blowback design utilizing manufacturing techniques that give it the stylings of a more expensive marker, while lowering the cost to the consumer. The Stryker marker tested for this review was a part of the Stryker STR-1 Player's Pack, which included the marker itself, a ViewLoader 200 round hopper, a set of JT paintball goggles, pull-through squeegee, paintgun oil, hex-wrenches, barrel plug and disposable 3.2 ounce CO2 cylinder with adapter. Basically the kit contains everything needed to play paintball except for a chronograph and paint.

The Stryker STR-1 has the look and style of more expensive paintball markers that are manufactured with multi-axis milling to incorporate smooth sweeping lines, and polished to a high lustre finish before fade anodizing is applied.

The Stryker design team achieved this same style instead using less expensive manufacturing methods better geared toward the high production volumes associated with an entry level marker. The Stryker body is actually die-cast (liquid metal is poured a multi-piece mold) in two parts. The receiver is cast in two halves, allowing internal surfaces to be defined by the cast, so that the passages for the bolt and hammer would not require extra steps of machine work.

Both the left and right sides of the barrel attachment point are cast as part of the left receiver half, allowing for full 360 degree barrel threads to be machined into them. Because the alloys used in die casting do not accept anodizing consistently, the Stryker STR-1 is instead finished with a durable sprayed enamel that fades from a greenish grey to silver and is matched in the barrel's finish.

Topping the marker is a JT Gorilla Grip feed collar that attaches to the receiver's feedneck base via machined threads, and locks securely by friction against an o-ring. The feed collar is made of aluminum with a series of rectangular openings in its sides. Over the aluminum body is a rubbery sheath with rectangular pads that stick through the openings in the metal.

The is result a friction grip feedneck that quite solidly held a variety of loaders during testing without any need for adjustment or clamping, including VLocity Ricochet and of course the included ViewLoader. An unsanded HALO proved too large to fit.

Extending from the top of the Stryker is its cocking knob, which also links the bolt in the upper tube to the hammer in the lower tube. A detent ball bearing in the bolt locks the knob in place securely, but allows it to be pulled quickly up and out, at which point the bolt can slide out the rear of the marker for pull-through cleaning access.

The STR-1 bolt has the look of a machined Delrin bolt, a feature typically found on more expensive markers. In actuality, it is injection molded, also reducing cost, and it is made of a polymer slightly stiffer than Delrin.

A pair of o-rings surround the gas port in the forward portion of the barrel, while another provides a sliding surface in the rear.

The front of the bolt has an unusual design, one that would increase cost in a machined bolt – its front face is radiused so that it extends the cylindrical shape of the feed path down into the breech, and has increased contact area with the paintball. Increased contact area means that the force of bolt impact will be distributed over more pf the paintball's surface, which should reduce the risk of a broken paintball.

Printed on the bottom of the Stryker bolt is the phrase “This Side Down” though the lettering began to wear off after only a few hundred shots during testing. Also in raised lettering in the center of the bolt is text reading “This Side Up.” These two steps will help newer players avoid a mistake that is all too common with stacked tube blowback markers – installing the bolt upside down, which results in little to no velocity, as it places the gas entry hole on the top, away from the gas port in the receiver.

In the rear of the marker is its back plug with integrated velocity adjuster. A quick-strip pin locks the plug in place, and its removal allows easy access to the hammer, mainspring and bumper. Care is needed during re-assembly to ensure that the hammer stays oriented vertically. If it rotates to one side, the hole for the link pin will not be properly aligned.

The grip frame for the marker is injection molded polymer, giving it strength while remaining light weight. It includes a Colt 1911 compatible wrap-around rubber grip, and an aluminum two-finger trigger with cross-block trigger safety. The trigger and sear pivot on pins that are friction fit into the grip frame.

A painted brass bottom-line ASA is connected to the bottom of the Stryker, and includes a feature not often seen elsewhere – a screen filter to protect the marker's valve from debris either in the CO2, or introduced to the ASA during tank changes.

The Stryker bottom-line uses diagonal screw placement for its mounting, similar to those found on Spyders as opposed to the more common centered 10-32 standard, however the grip frame also has screw holes which allow for another two screws diagonally opposite.

A monofilament braided hose connects the bottom-line to the gas-thru grip. Although it is styled like the vertical regulator found on many stacked tube markers, it does not use ASA threads to connect to the receiver, so it will not accept a standard vertical regulator as an upgrade.

In the front of the marker lies its valve chamber. In the 1990s, a number of stacked tube markers built for CO2 only performed reliably on compressed air if modified with “low pressure chambers” which replaced the flat plug on the front of their valve chamber, providing more room for air to be staged next to the exhaust valve. Although designers have since designed markers with larger chambers to start with, the “LPC” created a look that endures today, and is echoed in the Stryker's valve chamber plug.

The stock Stryker STR-1 barrel is ten inches in length, and made from a material typically only found in custom built to order barrels – brass. Six rows of six ports are aligned near the muzzle forming a muzzle brake.

From a manufacturing point of view brass is advantageous as a barrel material because it is relatively soft, meaning it can be machined quickly. In the mass production business time is money, and money saved means a more affordable product for the player. The chief drawbacks to brass also have to do with its softness.

Although it can not be anodized, brass can be enameled, and the Stryker barrel has the same finish as the marker's body. Unable to benefit from the protection of anodizing, the barrel's interior should be guarded. Dirt in the barrel can scratch its finish when propelled by a paintball.

From a player's perspective, brass as a barrel material has a couple of key benefits as well. It has a low friction coefficient, which minimizes drag on the paintball, helping marker efficiency. It also polishes nicely to a very low-friction surface, and the Stryker STR-1 barrel is polished bright and smooth at the factory. Should it ever become tarnished or rough the end user can easily polish it back to its original shine with a fleece barrel swab and readily available brass polish.

Answering the question asked by many new owners of paintball gear - “Where can I get my CO2 tank filled” is the Brass Eagle 3.2 ounce pre-filled CO2 cylinder. Looking like a 12 gram CO2 cargridge on steroids, the cylinder provides a single use disposable gas source usable for several hundred shots.

The CO2 cylinder screws into an aluminum male ASA adapter that has a hollow pin to pierce the top of the CO2 cylinder. The system is used by screwing the adapter into the Stryker's bottom-line ASA, then screwing the CO2 cylinder into the adapter.

Although the CO2 adapter contains a pin valve that should allow the cylinder and adapter assembly to be removed and moved to another marker without emptying, the cylinder's instructions advise against this, and during testing for review, it was found that under pressure the adapter seized into the marker's ASA with a strong enough grip to make this impractical.

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