Thompson Center Dimension No. 8402 243 Win., $679
Gun Tests magazine tested two hunting rifles in the April 2013 issue. Here’s an excerpt of that report, “Versatile 243 Win. Bolt Actions: Howa’s 2N1 Versus Thompson,” used with permission:
Lost in the current frenzy to hoard any and all Modern Sporting Rifles are fresh innovations being applied to bolt-action rifles. Not only are new manufacturing techniques making “minute-of-angle” bolt guns less expensive but more versatile, too. In this test we will evaluate two bolt action rifles chambered for 243 Winchester that offer something extra. The $641 Howa/Hogue Youth 2N1 rifles come with two different stocks so that the same Howa M1500 action will accommodate more than one shooter. Both stocks are manufactured by Hogue, using the OverMolded technique.
Thompson Center Arms’s $679 Dimension rifle offers the ability to accept different-caliber barrels so that the same rifle, or as the manufacturer prefers “platform,” can be used to hunt a wider variety of game. The Dimension bolt-action platform can be fit with any one of four groups of Locking Optimized Components (LOC) listed as series A, B, C, and D. The A series accommodates 223 Remington and 204 Ruger ammunition. Series C Dimension rifles can swap barrels for 270 Winchester and 30-06 Springfield, while the Series D includes 7mm Remington Magnum and 300 Winchester Magnum. Our Series B Dimension rifle offered the most versatility, able to accept alternate barrels for 22-250 Remington, 7mm-08 Remington, and 308 Winchester as well 243 Win. Thompson Center claims a 1-minute-of-angle accuracy guarantee no matter which caliber is chosen.
To test each rifle, we applied a simple accuracy test consisting of shooting from the 100-yard line at American Shooting Centers in Houston using a Caldwell Tack Driver rest for support. The days leading up to our tests were sunny and mild. But our tests days were rainy. Afraid that using paper targets would make archiving difficult, we acquired a supply of Caldwell Tip Top plastic-coated targets with 8-inch Bulls Eye. Impervious to water, they produced razor-sharp definition of each bullet hole. The targets measured 8- by 10- inches overall, and our shots matched the size of the holes that were pre-cut for saving in a three-ring binder. Velocities were recorded by an Oehler 35P Chronograph, which is back in production (Oehler-Research.com).
Our test ammunition consisted of three choices featuring three different types of bullets. First, we tried Winchester’s 80-grain Jacketed Soft Point, which despite new packaging is the same round used in the February 2013 test of 243 Winchester bolt-action rifles. In addition, we tried a second 80-grain round, this time from Black Hills Ammunition topped with Hornady’s GMX bullet. Gilding Metal eXpanding bullets are expanding monolithic bullets fashioned from the same material Hornady uses to jacket its bullet. The maker claims less fouling than solid copper and the GMX bullet features a grooved bearing surface. With so much luck in our last test firing lighter-weight bullets, we also tested with Black Hills 58-grain V-Max ammunition. Hornady V-Max bullets are lead-core jacketed bullets that feature a polymer tip.
For optics we decided to continue shooting with the 4-16x50mm Steiner Predator Extreme scope we enjoyed so much in our previous tests. Its clarity helped us cut through the somewhat dim, overcast light. From the 100-yard line, 8x was all the magnification we needed. The Howa rifle made no such claim, but Thompson Center guaranteed minute-of-angle accuracy. We wondered if either manufacturer was being modest.
Thompson Center Dimension No. 8402 243 Win., $679
Thompson Center’s catalog is filled with switch-barrel firearms, including handguns, shotguns, and rifles designed for rimfire, centerfire, and blackpowder ordnance. The purpose of the Thompson Center Dimension is to provide versatile firepower. Within the Dimension groups A, B, C, and D, we chose a group B rifle because we think it had the greatest versatility. At the low end, the 22-250 Remington can be used for Varminting. And to our way of thinking, 308 Winchester should cover just about anything else for tactical or hunting needs. Our choice of 243 Winchester would be ideal for small whitetail deer and the 7mm-08 for larger specimens.
Actually, any Dimension rifle can be changed to any caliber in any group. But once you choose a caliber outside of your original group, a new bolt, magazine, and magazine housing will be needed in addition to the new barrel. According to the instructional DVD included with the rifle, only the stock, receiver, and trigger assembly make up the common platform.
The Dimension rifle has several distinctive features aside from caliber versatility. The ventilated buttpad can be attached with or without one or two spacers in line. The black synthetic stock itself was curved with a raised comb. Its sloping profile might be visualized as a cross between a Bavarian style and Monte Carlo-shaped buttstock. The entire stock offered a rubberized finish, but there were separate inlays of softer gray rubber at the steep pistol grip and along the forend. The D-shaped trigger guard also had a rubberized coating. The barrel was free floated, and the forend sat well below the surface of the barrel to accommodate a variety of barrel sizes and contours.
The three-round magazine was polymer, and the release latch was located on the front edge of the magazine body. The receiver was alloy, and the bolt knob was unusually large. The bolt-handle arm was relieved on its outer surface, and the knob’s core was relieved to reduce weight. The same bolt is used per each series of components, and complementary parts are marked with their series-letter designation. Extra barrels, including a magazine, cost about $240. Matching bolts sell for about $150 at Cheaper Than Dirt. In addition to the instructional DVD, a Safety and Instructional Manual was supplied. One disclaimer at the end of the DVD says that the DVD is not a substitute for the printed manual. We think it should be, at least in part. Here is why. If you rely only upon the manual, then you will struggle with removing and installing the bolt and probably mar the stock in the process. Instructions on page 27 of the manual for removing the bolt were completely opposite of what is demonstrated in the DVD.
The proper way of removing the bolt is to first raise the handle and pull back the bolt until it stops. Press in the release and pull the bolt free. Reinstalling was the same as in the book, but in our view was too vague regarding many finer points, such as seating the bolt stop into the correct groove on the bolt. Sometimes the fluting tricked us into releasing the lever prematurely. The bolt release was heavily sprung, and its contact surface was peaked instead of flat, making it uncomfortable to press should the bolt become jammed.
Realizing it would take some practice before we felt confident performing the simple task of pulling the bolt in and out of the receiver, we were worried about the process of changing calibers. But our fears proved unfounded. We didn’t actually have another barrel to change to, but we thought we’d take it apart, put it back together, and shoot some representative groups. The takedown and rebuild actually didn’t take much longer than swapping Hogue stocks on the Howa rifle. The supplied LOC leverage and torque tools were the stars of the show. After clearing the rifle and removing the bolt, the Allen wrench at the end of the leverage tool was used to loosen the screws fore and aft of the trigger guard.
There was no possibility of losing the screws because they stay captured with the stock. To proceed, remove the barreled action and place it upside down in a rest. Screw the V-block feature of the locking tool into the tapped hole at the bottom of the receiver. The two holes marked L for loosen and T for tighten now face forward toward the muzzle. Insert the round end of the torque tool into the hole marked L, making sure the teeth on the ratcheting end of the torque tool mesh with the teeth on the barrel ring. Moving the handles together breaks the seal on the barrel ring. You can now unscrew the ring by hand and pull the barrel free of the receiver. The rebuild asks only that you place the round end of the ratchet tool into the hole marked T. The ratchet feature of the torque tool will click when the barrel ring is tight. The strength necessary to loosen or seat the barrel was minimal.
At the range we noticed that the Dimension’s trigger seemed soft in contrast to the Howa. We thought of adjusting it, but it seemed to improve as the rifle was shot, so we left it as delivered. Trigger-pull weight was measured to be 4.5 pounds at the conclusion of our accuracy tests. According to the manual, trigger-pull weight was adjustable by turning a screw located atop the trigger assembly beneath the bolt. The trigger-adjustment tool illustrated in the manual was not supplied, but all that was necessary was a .050 Allen wrench. However, turning the screw counterclockwise as prescribed in the manual had no measurable effect on trigger-pull weight. A factory representative said that it must already have been at its lowest point of resistance.
We mounted our Steiner scope on the supplied two-piece mounts. One optional piece available is a bridge-type mount (part number 9979, $97 from Cheaper Than Dirt). Clamping on to the integral mount atop the barrel, the rear of the bridge mount bolts on to the receiver. This enables the scope to stay with the barrel when changing calibers and maintain the appropriate zero.
Our range time with the Dimension rifle was considerably more rainy and windy. But with the patience to wait out gusts of wind and the confidence inspired by our Steiner Predator Extreme scope, we were able to live up to the minute-of-angle claim with two of our three choices of ammunition. The top performer was again the 58-grain V-Max rounds from Black Hills Ammunition. Fired from the Dimension, five-shot groups ranged in size from 0.6 inch to 0.9 inch across. The 80-grain rounds averaged 0.9 inch and 1.2 inches across for the Black Hills and Winchester rounds, respectively. Integrity after reassembly was maintained and groups shot after the rebuild were just as impressive as those shot during our earlier range session.
Our Team Said: Just when we thought we were testing a couple of merely good hunting rifles, we loaded the Dimension with Black Hills 58-grain V-Max ammunition and put 11 shots inside the X-ring with nine of them touching. The unusual stock configuration was comfortable, offered good index, and cheekweld. Caliber change proved to be so easy that the prospect of putting together a collection of different caliber components for our Dimension platform was a very real temptation.