Pre-Season Gun Maintenance,
by Ron Dague, Sinclair International
I give my rifles a pre-season check before the shooting season starts. This starts with a general inspection starting with the butt-plate or recoil pad and making sure that all the screws and adjustable parts (on an adjustable butt-plate) move freely up or down and side to side. If you got caught in rain some of these screws and adjustable parts may not move when needed. I disassemble parts as needed and put rust preventative or a light oil and/or grease on threads and sliding parts. On rifles with recoil pads and fixed butt-plates, make sure the screws are tight and that holes in the stock aren’t stripped out. Make sure there are no cracks in the stock and around the butt-plate. If the recoil pad is glued-on, just make sure it hasn’t come loose.

Next I take the action out of the stock and check for cracks and wear marks. I look at the bedding to make sure that oils and cleaning solvents have not damaged the bedding. While the action is out of the stock, I look for any surface rust or dirt/dust in the recoil lug area and magazine well. Clean as needed and repair or re-bed if needed.

Trigger Assembly and Action
With the barreled action out of the stock, it is a good time to spray out the trigger with cleaner. I use Ronson oil or lighter fluid. [Editor’s Note: Some trigger-makers advise against using any kind of lubricant, grease or oil — so plain lighter fluid is preferred.] After the trigger is cleaned you may want to check the trigger pull weight. If you don’t feel comfortable doing this, take it to a gun smith and have it checked. It is worth every penny to not have a trigger issue and/or a safety malfunction. I also take the bolt apart and clean the firing pin spring and bolt housing with Gun Scrubber or automotive brake cleaner. Then lube the firing pin-spring and firing pin with light oil. I use Kel Lube and/or Butch’s gun oil. Put a small dab of gun grease on the [bolt locking lugs] and cocking ramp.

I will also spray the outside of the action and barrel and give that a light coating of oil for rust prevention. I clean the action with Sinclair’s action cleaning tool. Don’t forget to clean the bore. Even though you didn’t fire the rifle, this makes sure nothing obstructs your barrel.

Checking Metal Fixtures and Fasteners
Next I look at the trigger guard and hinged floor plate and make sure it works as designed. Make sure there are no cracks in the trigger guard from an accidental drop. Check guard screws and /or action screws for tightness and tighten to proper spec. There are torque specs for this, but on wood stocks the wood can crush and this should be checked throughout the year as weather change can affect this. My entire collection of rifles are bedded and I just tighten them just snug with screw driver or Allen wrench. The rimfire rifles have a spec of 55 to 74 inch/lbs and I think would carry over to center fire as well. I would caution you about torque wrenches as you need a good quality wrench, and read the directions on how to use it. You can over torque if not careful. Check the swivel studs and bipod to make sure there tight as well. You may want to take scope off and check the base screws and check the rings.

Test Fire the Rifle After Maintenance
After all cleaning and is done and everything is reassembled, take a few rounds out to the range and test fire to make sure everything works as it should. Don’t forget to run 3-5 rounds through the magazine at least two times for function. I look at this as preventive maintenance on the rifle. If you give it a look over you shouldn’t have any trouble during the rifle matches or hunting trip.

Ron Dague
Certified Reloading Instructor
Certified Range Safety Officer
Email: rond [at] sinclairintl.com
Phone: 800-717-8211

T/C’s Dimension rifle is definitely innovative; there is nothing like it on the market anywhere near its price range (MSRP is $648.00 with tools). For a walking-around deer hunter who is satisfied with factory barrels, and who doesn’t shoot with a rear bag, the gun will probably have appeal. On the other hand, varminters won’t be impressed — the stock won’t work well with a bipod or rear bag, and T/C will be the only source for barrels. The nature of the design, for practical purposes, precludes the use of affordable 3rd-party barrels. You won’t be able to buy a Shilen or PacNor prefit barrel, as you can for a Savage.

Factory Promo Video (Loud Soundtrack — turn down speakers before playback!)

Action Features
Pro: One size fits all — single hard-anodized aluminum action can be used to shoot multiple chamberings from .204 Ruger to .300 Win Mag with bolt, barrel, and magazine swap. For all chamberings, T/C guarantees 3-shot accuracy of one MOA with premium ammo.
Con: You have to replace complete bolt assembly to go from one family of cartridges to another (e.g. from .308 Win to Magnum). This is much more expensive than swapping a bolt head on a Savage.

Barrel Fitting
Pro: Barrels can be quickly exchanged using provided tools.
Con: Bolt recesses are machined into barrel extension section, so barrels must be supplied by T/C. We were told that both bolts and barrels “absolutely have to come from Thompson/Center”.

Stock Features
Pro: Stock is lightweight with rubberized surface texture — good for wet climates.
Con: Stock is ugly. Forearm too flexy to use with bipod. Concave arc on underside of buttstock is terrible for use with rear bag. Stock finish tends to retain dust and grit.

Scope Mounting
Pro: T/C offers a bridge scope base that mounts to the barrel (like on Blasers). This allows an optic to stay with a barrel — so you could have a low-power close-range scope mounted and zeroed on one barrel, with a higher-power variable scope on another barrel.
Con: If you keep optics on the barrels, you need to buy a separate bridge for each barrel. That’s an added expense, plus many hunters can’t afford multiple scopes anyway. Thankfully, conventional Weaver bases can be fitted on top of the action.

Commentary: On viewing and handling the rifle, and watching the assembly process, it was obvious that some intelligent, clever engineering went into the gun. The AR-style barrel engagement system functions very well — the whole gun can be disassembled in under one minute. T/C provides some fairly sophisticated assembly tools with the gun, including wrenches that automatically set correct torque values. That’s cool. The gun is relatively light and balances well. On the other hand, the stock design fails in many ways. The fore-arm is short and too flexy for serious use with bipod. The curving underside of the buttstock is a odd-looking, but what is worse, the curve is just about the worst possible profile for use with a rear sandbag. Most observers thought the gun was ugly.

T/C Dimension Caliber Groups
The T/C Dimension LOC™ System has 7 parts — a universal stock and receiver that accept multiple barrels, magazine groups (magazine and housing), bolts and bridge scope mounts. Dimension hand tools work with all Dimension rifles. Interchangeable parts are stamped with letters: A, B, C or D. Match the letter on the barrel with the one on the bolt and magazine group.

A Family: .204 Ruger, .223 Rem
B Family: 22-250 Rem, .243 Win, 7mm-08 Rem, .308 Win
C Family: .270 Win, .30-06 Sprg
D Family: 7mm Rem Mag, .300 Win Mag