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SOG DonationsWhat is the difference between the 6.8 spc I and the 6.8 spc II and can I use the same barrel for both?
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The SPC l is obsolete and not made. The Il is what is being chambered these days. The ARP (AR15 Precision) is the chamber that most 6.8 aficionados use. They all will safely chamber the 6.8 SPC I factory ammo. There are some commercial houses loading to SPC Il. The ARP will shoot that too, and more, ie hot handloads.
Blackstone Arms is buying out AR15 Perfomance and has taken over the 6.8 barrel business. They were the only ARP authorized builder so it was a natural fit when Harrison decided to retireā¦
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I looked at some uppers and I donāt remember what brand but a good amount more than 556. Maybe because itās a multi purpose caliber.
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They all are Multi anymore. Difference in price is in quality of components usually. Thatās why we roll our own here. We have one tailormade, a older S&W M&P-15 in 5.56 NATO. Everything else is Aero or Seekins and is assembled by us with parts selected by us in various chambers/calibers. 223 Wylde, 224 Valkyrie, TAC 6, 6.8 SPC ARP, and looking at maybe a 20 Practical for the Dogtown.458 SOCOM is still tempting too. They all will fit any AR-15 Spec Lower. Thatās the beauty of an AR.
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So, i should get a 6.8 now?
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Too early to make a long-term prediction on whatās going to happen with the new Sig 6.8, but it is likely going to be rather expensive (both in ammo cost and rifle cost) for some time. Itās just too different an animal to make easy adaptations of stuff that is already on the market, increasing the development costs for any manufacturer wanting to join in.
6.8SPC didnāt get picked up by the military as a widespread replacement for 5.56NATO, as some were expecting when it came out, so it will not see the pricing advantages of military contract overruns being sold on the civilian market. On the other hand, Biden seems to be trying to eliminate the option of companies being able to sell military contract overruns of 5.56NATO on the civilian market, so 5.56 may be losing that ammo pricing advantage.
If you have considered getting into 6.8SPC, but held off due to concerns about bugs being worked out of the system, the shift to 6.8SPC II seems to have taken care of that, but I doubt pricing is going to change much, other than the pricing changes that are hitting the entire market (panic buying, etc). I jumped in early, then put the caliber on a back burner when the chamber issue (a small error in the chamber drawing that was submitted to SAAMI, if my fuzzy memory can be trusted) started getting some discussion on forums. At some point, I need to look up the chamber drawings for both 6.8SPC and 6.8SPC II, to see if itās possible to āfixā my old 6.8SPC barrel with a 6.8SPC II reamer, but too many other projects have a higher priority.
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I think it will take some more time to iron out the bugs in the 6.8 caliber. Engineers will make smart compromises and refine the designs, like they did with the M16, the M4 carbine, and the Mk18. It was a while before the bullet weight and construction, powder choice, twist rate, barrel length, action materials, and maintenance recommendations were settled, in their various target applications and markets. I expect the same for the 6.8.
So Iām watching and waiting.
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I think I would go with the .556. If the military is phasing it out in favor of the 6.8, that leaves more for the civilian market. Plus you have the added benefit of MOST rifles using both .556 and .223 so again, doubling down on ammo availability. Another benefit is a possible price drop in cost of the .556 due to decreased demand from the military. Take my opinion with a grain of salt because right now, neither is in the budget for me. As much as I would like a .556, a new 9mm PCC is in my near future for USPSA competitions.
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A 9mm PCC sounds fun.
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Yup, and good for close quarters self defense.
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I donāt know where I will find the money for the next upper but it will most likely get here eventually.
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Whatever ya do just make sure you can find ammo for it and the grendel aināt it.
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Even better if you can SBR it, not all states allow it. Mine wears a 7" (or is it 6"?) barrel and it gets around walls and barricades nicely. My 16" PCC was a PITA that way and was the reason I went to a SBR PCC.
A 300BLK would be much the same for HD. Of course it canāt be used for USPSA (maybe 3 gun legal? IDK.)
Edit: That should read ā300BLK handgun or SBRā. Since not all 300BLKs have short barrels.
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5.56 and 7.62x39 and stock upā¦308 after that. I can see the 6.8 stuff being all jacked up for a long time now that the DOD is changing to it, maybe 5 years from now it may all clear up and get standardized and be down pat. I donāt want anything to do with it at this point. my 2 cents.
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Well since I reload and it has longer effective range than 5.56 or 7.62Ć39 I am a 6.8 SPC ll advocate and user. Donāt get me wrong at a half the price 5.56 ammo is still a valuable tool, but if you reload the cost factor is diminished.
We still buy and use 5.56 but itās not a good choice for hunting except varmints. We use it so much as a range round weāre looking for a way to use the brass for something like a 20 Practical for the Dog Town.
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There is lots of 6.8 hornady custom on the shelves around here, that new place that opened has tons of it at cheap prices. it must not have caught on here as there is too much of it everywhere. but if the military adopts it, people will start buying it then.
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I may be wrong but it seems like a good idea to have something in the same caliber as the military.
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So you want to be able to do 10 second bursts from a Class IV high-power laser light projection system like the ISS?
The āIā part of ISS is all that should be needed to tip you off to the future NWO, along with the retiring of our Space Shuttle program , of course that was for safety reasons
hmmmm, no BS emoji 
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If your old enough to remember the 60s. This has all been hashed over before, just all that data is ignored.
Back then they played with .264, 284, and others that are now metric calibers, same old projectile.
7.62x61, then 7.62x51 are the best military calibers over the last 100 years. A quick, humane way of killing.
Dicking around with less will get are boys kilt.
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Whatever the new cartridge is going to be (I forget the name) itās said to have a 80k psi working pressure. YIKES! Is that what the various civilian 6.8s use as a working pressure? That sounds very high to me.
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