I have loaded the 6.8mm SPC using Remington , Hornady and Silver State Armory (SSA) brass.
The new SSA brass uses a small rifle primer and thus has a little more room for powder. It is also a touch less brittle than the Hornady or Remington brass and reloads better.
Most of my experimental 6.8 loads were fairly hot and I have one small batch of SSA brass that has been reloaded 5 times.
I still have about 500 rounds of SSA virgin brass that I have primed with two of three types of primers. It is good stuff.
Now that I have played around with the 6.8mm for a couple of years, I will be selling it off and starting a new project...
You really need to use a Lee Factory Crimp die for the 6.8mm if you are shooting it in an AR platform. There is all sorts of slamming going on in there...
Here are some of my experiments.
Rifle: Stag 16 inch flat-top, 1 in 10 twist SPCII chamber, A2 buttstock with Tubbs flat spring
Sights: Fixed 6 power Leupold. FXIII 42mm Heavy Duplex
Range 100 yards
Temp: Minus 3 F to Positive 05 degrees F , Negative 15 C average
Light: Flat fading light on snow.
110 Grain NOSLER ACCUBOND.
1:
Bullet: 110 grain NOSLER Accubond, boat tail
Powder: 26.6 grains, RL-10x compressed.
Primer: Remington 7 1/2 bench rest small rifle, hand seated
Brass: SSA
COL: 2.245 inch med roll crimp.
Velocity average: 2,329 fps 29 fps ES
1 inch group with last shot flyer no pressure signs
2:
Bullet: 110 NOSLER ACCUBOND Boat-Tail
Powder: 29.5 grains H-322
Primer: CCI-BR-4 Small Rifle, hand seated
Brass: SSA
COL: 2.260 inch Lee Factory Crimp
Velocity average: 2,532 fps 62 fps ES
0.30 inch group, with flyers on last round, High Pressure signs. Flat primers, ejector marks
3:
Bullet: 110 grain Nosler Accubond Boat-Tail
Powder: 29.0 grains H-322
Primer: CCI 450 MAGNUM Small Rifle hand seated
Brass: SSA
COL: 2.260 inch Lee Factory Crimp
Velocity average: 2,520 fps 55 fps ES
2.5 inch group, High Pressure signs. Ejector marks
4:
Bullet: 110 grain Nosler Accubond Boat-Tail
Powder: 29.0 grains H-322
Primer: Winchester Small Rifle hand seated
Brass: SSA
COL: 2.260 inch Lee Factory Crimp
Velocity average: 2,463 fps 24 fps ES
1.0 inch group, NO Pressure signs
5:
Bullet: 110 grain Nosler Accubond Boat-Tail
Powder: 29.0 grains H-322
Primer: CCI BR-4 Bench Rest Small Rifle hand seated
Brass: SSA
COL: 2.260 inch Lee Factory Crimp
Velocity average: 2,554 fps 14 fps ES
1.0 inch group, NO Pressure signs
6:
Bullet: 110 grain Nosler Accubond Boat-Tail
Powder: 28.0 grains H-322
Primer: CCI 450 MAGNUM Small Rifle hand seated
Brass: SSA
COL: 2.260 inch Lee Factory Crimp
Velocity average: 2,460 fps 41 fps ES
1.5 inch group, NO Pressure signs. Firing pin dragging on primer face
7:
Bullet: 110 grain Nosler Accubond Boat-Tail
Powder: 29.0 grains H-322
Primer: Federal 205 , Standard Small Rifle, hand seated
Brass: SSA
COL: 2.260 inch Lee Factory Crimp
Velocity average: 2,483 fps 33 fps ES
0.5 inch group, with flyer to 1.5in NO Pressure signs. Some firing pin dragging on primer face
8:
Bullet: 110 NOSLER ACCUBOND Boat-Tail
Powder: 29.0 grains H-322
Primer: CCI-41 MILITARY Small Rifle, hand seated
Brass: SSA
COL: 2.260 inch Lee Factory Crimp
Velocity average: 2,534 fps 32 fps ES fired at 35F temp
1.0 inch group, Flat primers,
110 grain Sierra Pro Hunter.
Rifle: Stag 16 inch flat-top, 1 in 10 twist SPCII chamber, A2 buttstock with Tubbs flat spring
Sights: Fixed 6 power Leupold. FXIII 42mm Heavy Duplex
Range 100 yards
Temp: Minus 3 F to Positive 35 degrees F ,
Light: Flat fading light on snow.
1.
Bullet: 110 grain Sierra Pro-Hunter SP, flat base
Powder: 29.0 grains H322
Primer: CCI-41 Military Small Rifle hand seated
Brass: SSA
COL: 2.260 inch Lee Factory Crimp
Velocity average: 2,495 fps ES-47 fps SD-21 fps
1.0 inch group some Pressure signs, flat primers
Loads very well, clean Brass
2.
Bullet: 110 grain Sierra Pro-Hunter SP, flat base
Powder: 31.0 grains AA-2230
Primer: CCI-400 Small Rifle hand seated
Brass: SSA
COL: 2.255 inch Lee Factory Crimp
Velocity average: 2,526 fps ES-75 fps SD-20 fps
1.0 inch group for 10 shots rapid fire, hot barrel,
Pressure signs, Loads very well , Clean Brass
3.
Bullet: 110 grain Sierra Pro-Hunter SP, flat base
Powder: 31.0 grains AA-2230
Primer: CCI-BR-4 Small Rifle hand seated
Brass: SSA
COL: 2.255 inch Lee Factory Crimp
Velocity average: Chronograph Failed at 8 below
0.28 inch group, Some moderate Pressure signs
Loads very well, Clean Brass
90 GRAIN SIERRA HP
1.
Bullet: 90 grain Sierra Hollow Point, flat base
Powder: 30.1 grains, H-322.
Primer: CCI-BR-4 bench rest small rifle, hand seated
Brass: SSA
COL: 2.245 inch Lee Crimp.
Velocity average: 2,705 fps 40 fps ES
1.5 inch group with last shot flyer to 2 Does not load well No pressure signs
2:
Bullet: 90 grain Sierra Hollow Point, flat base
Powder: 33.5 grains, AA-2230
Primer: CCI-BR-4 bench rest small rifle, hand seated
Brass: SSA
COL: 2.245 inch Lee Crimp.
Velocity average: 2,647 fps 43 fps ES
0.5 inch group with last shot flyer to 0.75 Does not load well No pressure signs
3:
Bullet: 90 grain Sierra Hollow Point, flat base
Powder: 27.5 grains, RL-7
Primer: CCI-BR-4 bench rest small rifle, hand seated
Brass: SSA
COL: 2.245 inch Lee Crimp.
Velocity average: 2,664 fps 47 fps ES
1.25 inch group Does not load well Some pressure signs
4:
Bullet: 90 grain Sierra Hollow Point, flat base
Powder: 27.0 grains AA 1680
Primer: CCI-BR-4 bench rest small rifle, hand seated
Brass: SSA
COL: 2.245 inch Lee Crimp.
Velocity average: 2,645 fps 74 fps ES
1.0 inch group Does not load well NO pressure signs
5:
Bullet: 90 grain Sierra Hollow Point, flat base
Powder: 28.5 grains H-4198
Primer: CCI-BR-4 bench rest small rifle, hand seated
Brass: SSA
COL: 2.245 inch Lee Crimp.
Velocity average: 2,883 fps 24 fps ES
1.0 inch group including flyers Does not load well HIGH pressure signs
Has potential for accuracy if it would load without hanging up.
This is MAX for my rifle. FIRED AT 28 degrees F..
Long Seated experiment. Does not work well in C-mag.
6.
Bullet: 90 grain Sierra Hollow Point, flat base
Powder: 28.5 grains, H-4198.
Primer: CCI-400 small rifle, hand seated
Brass: SSA
COL: 2.315 inch Lee Crimp.
Velocity average: 2,870 fps 65 fps ES
1.2 inch group flat primers
7.
Bullet: 90 grain Sierra Hollow Point, flat base
Powder: 28.8 grains, H-4198.
Primer: CCI-400 small rifle, hand seated
Brass: SSA
COL: 2.315 inch Lee Crimp.
Velocity average: 2,908 fps, 22 fps ES
0.40 inch group , with standard first and last round flyers to 0.75 in
flat primers , ejector marks
8.
Bullet: 90 grain Sierra Hollow Point, flat base
Powder: 29.0 grains, H-4198.
Primer: CCI-400 small rifle, hand seated
Brass: SSA
COL: 2.315 inch Lee Crimp.
Velocity average: 2,930 fps 37 fps ES
0.75 inch group, with flyer to 1.2 inch
flat primers, cratered primer strike, heavy ejector marks