Originally Posted By: jackhbrandon-i was under the impression that there was an SPC and SPCII round. i was also under the impression that depending on what your gun was chambered for, you could shoot one, but possibly not the other.
kind of like .223 and 5.56. i cant ever remember which it is, but if your chambered for .223 you can shoot both, but if your chambered for 5.56 you can only shoot 5.56.
is this not correct?
As has been stated, no, the .223 is the first Remington chamber. 5.56 is the freebore chamber, which means that it has a longer leade than the .223, allowing for increased pressures. 5.56 brass is also thicker than .223, so the brass can withstand the additional pressure as well. This allows for the use of .223 and 5.56 out of the 5.56 chamber, but not the other way around. Applying that to 6.8, the first 6.8SPC SAAMI chamber brought out by remington was the "223" of the 68 world. The new SPC or x43 chambering (which is all the same, but technically not, which is a can of worms all in itself) is the "556" of the 68 world. The SPCII or x43 denotation will provide a longer leade and offer increased pressure potential out of shooting in the chamber.
For 6.8, there is no commercial vendors, excluding SSA (SILVER STATE ARMORY) that produces a "SPC and a SPCII" ammo. That's just the denotation of the barrel/chambers. THe ammo you buy from Hornady, Remington, Corbon, are all commercial loads. This means that if I shoot with a SPC chamber, that they are safe, unless otherwise noted.
For SSA, Commercial are safe for these types of chambers as well. Unless you shoot the "Tactical" loads from SSA, then you are required to sign off on any liability, and declare you are indeed shooting with a SPCII chamber.
Handloading is also a caveat here. You can load up to max, or even further than some reloading manual's max (as they're based on SPC chambered guns), and for that gun, run ammo that would generally pressure swipe in a SPC chambered gun, but be fine in the SPCII chambered gun.
This I'm sure is even more confusing if you do not know what gun you have!... as I mentioned before, what upper assembly do you have (Is it a complete upper from a manufacturer) and does it have any markings on the barrel?