I have been hand-loading and shooting a couple 6.8mm ARs for a few years now. One 16 inch carbine and one 24 inch heavy barrel that I built up as a heavy varmint ( wolf & coyote) plus open ground caribou zapper.
It is an interesting cartridge that does much better in longer barrels than it was originally thought.
90gr Sierra HP28.8gr H-4198SSA/CCI-412.260col / LFC
3,115 fps0.75 inch group
Stag AR with 24 inch poly rifled Black Hole Weaponry Barrel12 power Pentex Scope.100 yards, rain, 12 knot winds, 42 degree F. All Loads SSA once fired brass. CCI 450 magnum primers (saving my military primers)Lee factory Crimp on all loads. Chronograph at 10 feet from muzzle.
90gr Sierra HP31.5gr AA-22002.219 in COLVel= 3,265 fps and a 0.50 inch groupDirty necks , semi flat primersMuzzle Energy 2,130 foot pounds, point blank hunting envelope 285 yards.
95gr Barnes TTSX31.0gr AA-22002.230 COLVel= 3,270 fps and a 1.0 inch groupDirty necks, semi flat primersMuzzle Energy 2,255 foot pounds, point blank envelope to 303 yards.Holds 1,000 foot pounds out to 375 yards.
100gr Nosler Accubond…BC = .32330.0gr AA-2200 CCI-BR4 primer2.253 colVel= 3,070 fps and a 1.0 inch groupDirty case necksMuzzle Energy , 2,099 foot pounds, point blank hunting envelope to 290 yardsHolds 1,000 ft pounds out to 350 yards
100gr Nosler Accubond BC=.32330.5gr AA-2200 CCI BR-4 primer2.253 colVel= 3,105 fps and a 2.0 inch groupDirty case necksMuzzle Energy , 2,141 foot pounds, point blank hunting envelope to 293 yardsHolds 1,000 ft pounds out to 360 yards
100gr Nosler Accubond BC=.32330.9gr AA-2200 CCI 450 primer2.280 colVel= 3,057 fps and a 0.75 inch groupDirty case necks, fails to feed 100% Ejector dingsFired at 10 below zero
110gr Nosler Accubond29.0gr AA-22002.260 colVel= 3,020 fps and a 1.4 inch groupDirty case necksMuzzle Energy , 2,228 foot pounds, point blank hunting envelope to 290 yardsHolds 1,000 ft pounds out to 425 yards.
110gr Barnes TTSX29.0gr AA-22002.280 colVel= 2,990 fps and a 2.0 inch groupdirty case necksMuzzle Energy 2,184 ft lbs, point blank envelope to 288 yards.
120gr Hornady SST BC=.40028.0gr AA-2200, CCI BR-4 primer2.252 colVel= 2,775 fps and a 1.0 inch groupDirty case necksMuzzle Energy , 2,052 foot pounds, point blank hunting envelope to 271 yardsHolds 1,000 ft pounds out to 400 yards
120gr Hornady SST BC=.40028.5gr AA-2200, CCI BR-4 primer2.252 colVel= 2,820 fps and a 0.50 inch groupDirty case necksMuzzle Energy , 2,119 foot pounds, point blank hunting envelope to 275 yardsHolds 1,000 ft pounds out to 425 yards, fired at 29 degrees
120gr Hornady SST BC=.40028.7gr AA-2200, CCI 450 primer2.287 colVel= 2,677 fps and a 1.00 inch groupEjector Dings, Fired at 10 below zero
120gr Hornady SST BC=.40028.9gr AA-2200, CCI 450 Magnum primer2.287 col Fired at 10 below zeroVel= 2,710 fps and a 0.50 inch main group 1st and last rnd flyer to 1.0 in Ejector dings
130gr Sierra Soft Point flat base27.0gr AA-22002.280 colVel=2,658 fps and a 1.0 inch groupDirty necksMuzzle Energy 2,039 ft lbs. Point Blank hunting range of 263 yardsHolds 1,000 foot pounds out to 425 yards.
130gr Hornady SST BC=.46027.2gr AA-2200, CCI 41 Military primer2.290 colVel= 2,570 fps and a 2.00 inch groupPressure signs OK, no dings, Ojive had to be crimped closeMuzzle Energy , 1,906 foot pounds, point blank hunting envelope to 256 yardsHolds 1,000 ft pounds out to 410 yards, fired at 10 degrees below zero
150gr Speer Soft Point Flat Base25.0gr AA-22002.280 colVel= 2,360 fps and a CLOVERLEAF HOLEdirty necks, semi-flat primersMuzzle Energy 1,855 foot pounds, Point Blank hunting range 237 yardsHolds 1,000 ft lbs out to 375 yards
150gr SPEER SOFT POINT 25.3gr AA-2200, CCI 41 Military primer2.291 colVel= 2,286 fps and a 0.50 inch groupNo pressure signs, clean cases, cycles well Fired at 10 below zero.