RELOADING
The 6.8mm SPC
Remington's military round and would-be sporter is a good match for the T/C Contender.
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The 6.8mm Remington SPC is a great medium-game round for the popular Thompson/Center Contender handgun. It uses .270-caliber bullets, a good bore size for medium game; the case has just enough taper to allow easy chambering and extraction in the Contender; and the case-capacity/bullet-weight ratio is well suited to 14-inch barrels.
Most important, since the 6.8mm SPC is based on the .30 Remington case, it provides an intermediate case diameter. That makes it small enough in diameter to keep back-thrust (force exerted on the frame under recoil) to an acceptable level--allowing specified chamber pressures to be handled safely--yet fat enough to provide good case capacity and thus velocities.
The 6.8mm SPC is not just a re-formed .30 Remington case. It has been strengthened to modern standards and is of a diameter that falls roughly halfway between the .223 and the .308. It is stronger than the .30-30 family of cases often used in the Contender and can safely be loaded to SAAMI specs in these handguns.
As soon as the specifications for the cartridge were finalized, JD Jones of SSK Industries built me a 14-inch Contender barrel in 6.8mm SPC, and I have worked with it extensively over the past year. It is superbly accurate and provides ample power for deer-size game, and recoil is mild compared to other Contender medium-game chamberings such as the .30-30 and 7-30 Waters.
The list of suitable powders for the 6.8mm SPC is a short one. Look to rifle powders toward the fast end of the burning-rate chart: H335, H322, Reloder 10X and IMR4198. I obtained best velocities with H322, but Reloder 10X provided the most consistent accuracy in my barrel with all bullet weights tested. Frankly, the gun shot so well that it was hard to tell the difference between most of the loads; when you're dealing with variations that amount to fractions of an inch at 100 yards out of a handgun, it's tough to keep human error out of the mix.
The downside to the 6.8 SPC as a hunting round is a lack of good bullets. To obtain usable velocities in the 14-inch barrel, you need bullets below 130 grains in weight. There just aren't many in .270 caliber, and those you can find are either frangible varmint bullets or big-game bullets built for high-velocity cartridges such as the .270 Winchester.
Hornady's 110-grain V-Max may be the best all-around choice for the Contender at this point. As a varmint bullet, it does tend to come apart at the 2,400 fps you will get at the muzzle in the Contender, but as velocity drops downrange, the bullet begins to perform more like something suitable for medium-size big game.
In contrast, game bullets such the 110-grain Sierra Pro-Hunter Spitzer and the new Barnes 110-grain Triple-Shock provide devastating expansion, penetration and weight retention at muzzle velocities, but expansion gets iffy as the bullet drops below 2,100 fps.
The good news is that the short, stiff barrels of Contender handguns tend to shoot different bullets of the same weight and velocity to the same point of impact. I use Barnes Triple-Shock bullets for close work on deer out to about 150 yards, and if a longer shot presents itself I switch to the 110-grain V-Max. Both bullets print to the same point of impact, and both are accurate in my SSK barrel.
The 6.8mm SPC is easy to load and not finicky as to powders, bullets, seating depths, etc. Case life is excellent, and little case trimming is required with repeated firings. In short, it is an easy case to work with, and excellent results can be obtained with minimal experimentation.
Always stay within the guidelines of published data, but when working up loads in the Contender, do not expect pressure signs such as flattened primers to keep you out of trouble. If it becomes difficult to break open the action after firing, back off the load. Fired cases should extract easily and smoothly.
Remington offers unprimed brass and loaded ammo, although the latter can be hard to come by. Hornady is gearing up to produce a couple of factory loads for the cartridge, and they should be available by the time you read this. Loading dies are readily available.
Thompson/Center Arms was one of the first sporting-arm makers to recognize the potential of this cartridge, and it chambers the 6.8mm SPC in both the Contender and Encore in handgun and rifle lengths. Hopefully, we will see more firearms chambered for this cartridge in the near future. (Editors' Note: We'll be testing an AR-style rifle in 6.8mm SPC in the near future.)
WARNING: The loads shown here are safe only in the guns for which they were developed. Neither the author nor Primedia assumes any liability for accidents or injury resulting from the use or misuse of this data.
| Bullet | Bullet Weight (gr.) | Powder | Primer | Case | Starting Load (grs.) | Maximum Load (grs.) | Muzzle Velocity (fps) |
|---|---|---|---|---|---|---|---|
| Sierra HP | 90 | H322 | Federal 210 | Remington | 29.0 | 31.2 | 2,635 |
| Hornady V-Max | 110 | Reloder 10X | Federal 210 | Remington | 25.5 | 26.9 | 2,378 |
| Hornady V-Max | 110 | H322 | Federal 210 | Remington | 27.0 | 28.9 | 2,443 |
| Barnes Triple-Shock | 110 | H322 | Federal 210 | Remington | 27.0 | 28.9 | 2,472 |
| Sierra Spitzer | 110 | IMR4198 | Federal 210 | Remington | 22.5 | 24.0 | 2,332 |
6.8mm SPC (Load Data)
