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Bore Sighting and Sighting in the Thompson Center Encore
This is a report on sighting in a new Thompson Center Encore Pistol in .308 Winchester. We loaded a number of both full and reduced, and one "CIA" assassin's load, and then tested the Encore's performance with the factory scope.
The "full" load was a Hornady 30 Cal 150 grain SST with a BC of about .371. The "reduced" load was a Nosler 150 grain spitzer. The "CIA assassin's" load was a "0" buck (.320) ball sized to .310. All three were loaded over Winchester factory .308 brass with large rifle primers. The full load was over 43 grains of Varget. The reduced loads were over 12.5 grains of Red Dot, 25 grains of IMR 4895, 10 grains of IMR 4227, 11.5 grains of Unique, 19 grains of IMR SR 4759, and 22 grains of 4198. The "CIA" load was over 3 grains of Red Dot.
The general rule of thumb to avoid dangerous instant detonation at reduced loads is to not go below half of a fast pistol or shotgun powder's maximum (Unique or Red Dot), and not below 2/3 of a slower burning rifle powder's maximum. Reduced loads are popular in Thompson Center pistols to tame the sometimes hefty recoil in cartridges like the .308, with barrels as short as the present 15". Some gunsmiths and reloaders consider using red dot or unique an unproven "wildcat" technique (adapting essentially shotgun powder to rifle loads), but this is not true: the Lyman cast bullet and reloading catalogs have had reduced load formulas for this combination for years! The web makes this looks innovative and mysterious; cast bullet loaders have known about it for years.
We first used the Leopold "Zero Point" magnetic bore sighter. This is technically known as a collimator. It is different, and far better, than the eariler Leopold or Bushnell magnetic bore sighters, because you can see through it to the target. This allows ONE SHOT adjustment. All these collimators are set for 25 yards "on the paper," which is the first ballistic crossover point for a 100 yard zero, but "on the paper" at 25 is NOT on the paper at 100!
For this reason, the very cool Zero Point's see through feature comes in handy. You sight the scope at collimator zero overlay, shoot one round at 25 yards, hold the collimator indicator over the target's bullseye, then readjust the scope for the actual impact hole (moving the collimator image to the actual bullet impact point at 25 yards--- "down" in scope clicks moves the "target" (collimator image) DOWN, "right" moves the image right). This gets you on the paper at 100 yards! All this fuss is to save a lot of expensive ammo getting you to zero.
Hold overs and unders are moot with the TC scope, as it has no mil or moa or inch dots in the reticle, so you've got to go by "gopher heights" etc. if you want to reach out. For pistol hunting, the humane rule of thumb is to consider it a 100 yard or less platform anyway, especially with reduced loads.
For full loads, you run the risk of both developing a serious flinch, and blowing most of your propellant's flash out the end of the flame-throwing crown anyway-- cool looking at night, but worthless otherwise. Hold unders at less than 100 yards are only a couple inches, so unless you're shooting mice, it shouldn't matter that much if you have a good 100 yard zero.
The "CIA" load is based on an assassin's gun platform using the T-C Encore Pistol. The "O" (.310) buck shot pellet is propelled only by primer and a few grains of fast burning shotgun powder, in a .308 cartridge, crimped mid diameter. This platform shoots silently and accurately at 25 yards, leaves no brass behind, and the projectile has no identifying forensic ballistic identity.
Smith Tactical has engineered a number of these packages and loads for various government and military entities, including several with lethal cores of fulminated mercury, bactratoxin, and others we won't mention.
For practical plinking (sans poisons), this is a fun load that costs nothing for "bullets." (A 5 pound bag of 0 (.320) or 00 (.330) or 000 (.360) or 0000 (.380) is about 20 bucks, and you can get about 18,000 rounds out of an 8 pound keg of Red Dot! Now, don't start thinking you've found a source for the tough to get .380 for your LCP!*
Also, 18,000 rounds would still have the little issue of brass and primers, even if you have the lead and powder! At this tiny load, barrel leading with the 0 buck is a non issue, even if you don't "mold your own" normally. It's still a great little squirrel gun, and a lot cheaper than $2X a box 17 HMR varmint rounds!
All the above loads brought in MOA groups (1") at 100 yards from the bench, as did the CIA at 25 yards. The T-C scope was adequate, but we'd recommend a field rest or bench rest, as even with their generous eye relief and tough recoil profile, these scopes bobble wildly at anything over 50 feet. And that's at 2.5X, at 7X-- forget freehand shooting! Remember: hold the GRIP TIGHT with both hands in any T/C! Do NOT shoot holding the front barrel piece with one hand, or you'll have a permanent hammer mark in your forehead with the 500 SW Mag, .308, etc. Rule one in Encore Pistols: HOLD ON TIGHT!
*The process for successfully implementing the CIA load requires a few "casting" techniques. First, slug the chamber and barrel of your gun, such as the TC here. The best method is to use Cerrosafe with a little wad of cotton. .309 is a good estimate, but it's far better to actually slug, so you see clearly lands and grooves, and can then micrometer check the ball. Next, size the original "0" ball with your Lyman sizer (or a dremel, carefully, with lubricant, keeping it round!). Some folks laugh at round balls, but they are surprisingly accurate, and even in the Civil War, the "Minie" would tumble if a little out of spec where the ball wouldn't. In any case, this is a 50 yard load, not sniping! It is quieter than an airgun (sounds like the single clap of your hands), and you can easily shoot one hole groups at 20 yards. Rats, skunks, squirrels beware, even in the city where neighbors would call the cops on any louder round! Black ops types use this load with a small custom .308 derringer that makes their mission silent, without the need for a silencer or large weapon.
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