Can you change out the barrel on a 6.8 SPC and run 5.56

Don-n-Texas

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Apr 17, 2011
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Houston now in Denton County
Can you change out the barrel on a 6.8 SPC and run 5.56. Is there any problems I’m going to run into?

My brother bought a DD thinking the military would adopt this cartridge. They didn’t and now with all that’s going on We think converting to 5.56 is a good option.
 
There are several common bolt face diameters used by multiple different calibers, e.g. .308, 6.5 Creed, and .45 ACP all use the same size bolt face. This is often due to new cartridges being developed from older ones by necking up or down, changing the shoulder location and angle, etc.

6.8 SPC is the parent cartridge to .224 Valkyrie, so you could convert the upper to that and keep the same bolt.
 
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apparently no one shoots it around here but me, I'm still finding 120Gr sst's on the shelf for $28 a box. I shoot a ton of hogs and deer with it. only used my 556 once this year because I wanted to see how it did and was reminded why I started using the 6.8 in the first place. 6.8 just hits harder.
 
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