Should I Prepare to Retire my 6.8 SPC [ Spec. II ] ? Any Comments & or Input ?

[pinzgauer]

I'd suggest keeping it. I run both 5.56 and 6.8 SPC using Robert MURG concept in the 2008 NDIA. ).

TLDR; snip (actually, I did read it in the follow-ups)

Summary:
Grendel won't work at 600 yards in Afghanistan based on some randos YouTube video so the Army decided it needed 6.8 sig fury therefore my (heavily emotionally invested) 6.spc is better

I'm not going to bother to address some of your anti-grendel myths. (Some things that are valid) This is an SPC thread.

Many of your points I actually agree with pertaining to intermediate cartridges.

There are many nuances between Grendel and SPC. You just wanted to point out the ones positive for SPC.

But the fact remains that an intermediate cartridge (SPC or Grendel) does not solve a problem the infantry current has. Or more accurately the trade-offs are not justified by the benefits. It remains to be seen whether the M5 will be worth the load out weight increase or if it's something from the good idea of fairy.

At least with the intermediate cartridge the only increase was the additional ammo weight for std loadout. With the M5 there is an additional weight with the carbine.

[1168]

TLDR; snip (actually, I did read it in the follow-ups)

Summary:
Grendel won't work at 600 yards in Afghanistan based on some randos YouTube video so the Army decided it needed 6.8 sig fury therefore my (heavily emotionally invested) 6.spc is better

I'm not going to bother to address some of your anti-grendel myths. (Some things that are valid) This is an SPC thread.

Many of your points I actually agree with pertaining to intermediate cartridges.

There are many nuances between Grendel and SPC. You just wanted to point out the ones positive for SPC.

But the fact remains that an intermediate cartridge (SPC or Grendel) does not solve a problem the infantry current has. Or more accurately the trade-offs are not justified by the benefits. It remains to be seen whether the M5 will be worth the load out weight increase or if it's something from the good idea of fairy.

At least with the intermediate cartridge the only increase was the additional ammo weight for std loadout. With the M5 there is an additional weight with the carbine.

I concur. I wouldn’t ditch a SPC if its what I had (I think OP should keep his), and it is more than adequate for many uses. Infantry isn’t one of them. You get more weight, less ammo, and reduced MPBR. When all of your best friends, plus a 240 or 3 are fighting as a team and there are grenade launchers and 249s integrated, the improvement in lethality is marginal, at best. There is essentially no benefit, all downsides, in that setting. For home-D, hunting, target shooting or LE work, none of this matters, so rock on.

[dpast32]

Hey '1168', Just a quick THANKS for your correction on the 14.5" / 5.56 velocity, I appreciate it. I've been digesting so very many assorted muzzle velocities, energy figures, trajectory data, etc, etc. In fact when I was just a kid back in the 1960's, my favorite reading material were the American Rifleman & the Remington Ammunition Catalog, as it almost always included all the related ballistics data. When I remember way back then, I distinctly recall all the now long gone calibers then available. I would read & read again, just dreaming about the day I could own my own firearms. But, it looks like I'm getting off topic here, so THANKS AGAIN.

Best, Dom P.

[dpast32]

Well, I've officially decided that it would be indeed foolish, [ aka stupid ] for me to sell off my 6.8 SPC Stag M-5, period !! For the purposes I initially purchased it, it performs each & every task I asked of it, & performed them all beautifully ! And, even though ammunition prices, & to a somewhat lesser extent availability can be 'limited' at the moment, I don't require all that much to accomplish what I obtained it for, which is basically home / self defense purposes. As it stands, I still have around 500 +/- rds available, & the bulk of it is excellent defense ammo, so what more or else do I truly need ? I have a few Optics which can be swapped back & forth as needed, so that's covered. As purchased, it didn't come with any Iron Sights, so I picked up a very useable ARMS M-40 Folding Rear Peep, which I sometimes prefer over Optics if you can believe that. ( Hey, I grew up on Iron Sights, & remember if you're primary Optic goes down or becomes damaged, guess what you're using ? ) One particular issue ( if it really is an issue to begin with ? ) is the fact that my Stag M-5 wasn't manufactured with the M-4 Feed Ramps, as were all Stag 6.8's at that particular time. After some thought, & investigation, I came to the conclusion that it really didn't require the M-4 Ramps, due to it being Semi-Automatic only. IIRC, the M-4 Feed Ramps were introduced primarily to assist function during Fully Automatic fire, not Semi, or at least that's what I was advised. ( If I'm wrong on this point, please correct me ? ) Also, I've never heard of any Feeding related issues pertaining to the Stag 6.8's, so perhaps the 'proof is indeed in the pudding' as they say. Anyways, I plan on keeping my 6.8, for the only potential concern I can currently think about would be ammunition availability sometime down the road. Hopefully, there's enough of us 6.8 users to keep some Company making a few runs yearly ? And, if ammo does become an issue, well, then I guess I'll just have to swap the 6.8 Upper with someone more available. THANK YOU Guys, for all the kind assistance.

Best, Dom P.

[constructor]

Back around 2008 they said the 6.8 has 80% of the performance of the 308 with less recoil and the weight of an AR15, it was just a general broad description. 2 years ago I decided I wanted to build a 16" 308 and this summer I finally had time to reload or try to work up some good loads using the MK319 130gr bullets for this 16" 308(45gr powder). When checking velocity and ES I noticed the velocity was low, only 150fps faster than the 6.8 can propel 130gr bullet with 33% less powder(30gr). I tried almost every powder I could find in the 308 and could not get the velocity up any higher than the Federal mk319 ammo. The 308 really needs a longer barrel to allow time for that extra 15gr of powder to burn and get the velocity out of it.
Yeah a 14.5 or 16" 308 may look cool but it's not very efficient and the old claim of the 6.8 having 80% of the performance of the 308 is fairly close. I think I'll stick with the 6.8 for short barrel work and leave the 308s at 18" or longer.

[Stopsign32v]

You're still comparing a 6.8 bullet vs a 7.62

I would take a 7.62 bullet traveling 150fps faster than a 6.8 vs a 6.8 bullet traveling 150fps slower than a 7.62...If we are just talking performance.

[Disciple]

When checking velocity and ES I noticed the velocity was low, only 150fps faster than the 6.8 can propel 130gr bullet with 33% less powder(30gr).

Is that 6.8 velocity with mass market bolts or something special?

[constructor]

Is that 6.8 velocity with mass market bolts or something special?

Carp 158 or 9310, Microbest is good, 6.8 bolts don't break like Grendel bolts.

[constructor]

You're still comparing a 6.8 bullet vs a 7.62

I would take a 7.62 bullet traveling 150fps faster than a 6.8 vs a 6.8 bullet traveling 150fps slower than a 7.62...If we are just talking performance.

I'm looking at more than just performance, weight of the rifle, weight of ammo and recoil. If I'm building a CQB-300 rifle I would rather have a smaller lighter rifle with a better mag capacity. If I'm going to shoot 600 yds I'm not going to chop a 308 barrel short.

[1168]

If I'm building a CQB-300 rifle I would rather have a smaller lighter rifle with a better mag capacity.

strongly agree.