The Down Range Forum

Member Section => Tactical Rifle & Carbine => Topic started by: Ocin on March 11, 2008, 09:19:39 AM

Title: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: Ocin on March 11, 2008, 09:19:39 AM
Hey everyone,

These new cartridges mentioned above are better then the 5.56 Nato round and compatible with an AR 15 lower. Each is the best, according to its manufacturer that is. And there is just my problem: all I can find is what the manufacturars say/claim about their round and, surprise, it is THE BEST round ever made or anyone ever came up with.

I was wondering if there is anyone who has some actual experience with these cartridges though or could direct me to some independent information about those cartridges.

Many thanks.
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: Bidah on March 11, 2008, 01:41:52 PM
My first question is what do you want or expect them to do?  That will help to steer you towards one or the other hopefully, as they are not all the same performance.

I do not know of very many independent reviews, outside of what you may see posted on the forums.

-Bidah
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: Ocin on March 11, 2008, 03:42:35 PM
I have very little experience with firearms to be honest, so i do not really know what to expect. What i would like to do is to participate some combat style shooting matches.
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: texcaliber on March 11, 2008, 06:07:25 PM
I have very little experience with firearms to be honest, so i do not really know what to expect. What i would like to do is to participate some combat style shooting matches.


stick with the 556NATO IMHO. Save your money on the overly priced ammo which you asked about man, and spend it on a better AR.

Tex
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: DDMac on March 11, 2008, 08:59:35 PM
For use against no armor BGs (bad guys)  within 150 yards, do any of the newest and best rounds offer a significant enough advantage over 5.56mm to warrant a new upper? I am assuming they all run on AR platforms.
 Mac.
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: Bidah on March 12, 2008, 10:16:25 AM
If you are looking to do some competition, I would also suggest that you use 5.56.  While 6.8/6.5 is more expensive, it is not much more so than what 5.56 is now.  Availability however could be an issue depending on where you are.

The 6.5/6.8 are great rounds, although somewhat new, and make a pretty good hunting round as well.  If I had an AR, and did not have an investment in .308, and wanted to hunt, going to one of these would be my first choice.

-Bidah
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: kilopaparomeo on March 12, 2008, 05:25:00 PM
+1 to comments above.

If you are looking to play shooting games, or if you are looking for a SD round and believe your engagements are within 150 yards, 5.56 is your round.  In fact for matches, 5.56 will be cheaper and allow you to be faster because of lower recoil.

Here's my quick assessment of the 6.5 Grendel vs the 6.8 SPC debate.  Both hit harder than a 5.56 at all ranges.  Out to 300-400 yards or so, there is very little difference between 6.8 and 6.5...although 6.5 will be just slightly flatter in trajectory.  Beyond 400-500 yards, 6.5 G will take over with more retained velocity and flatter trajectory.  6.8 SPC will have the theoretical edge in reliability because of the slightly more tapered case...probably only will notice that in full auto. 

So, if you want something for short range and/or games -- 5.56
If you want a harder hitting round in an M4/intermediate range set up -- 6.8 SPC
If you want a harder hitting round that will carry out further with 20-24" barrel -- 6.5 Grendel

That said, I just set up a 24" Overwatch upper on a PRS-stocked lower for my DMR rifle -- in 6.5G
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: Pathfinder on March 12, 2008, 07:50:23 PM

stick with the 556NATO IMHO. Save your money on the overly priced ammo which you asked about man, and spend it on a better AR.

Tex

Tex -

This one comment caused me to stop and rethink what I was doing. My intent was to build up a 6.8SPC for the harder hitting power of that cartridge. Then I started looking into what the components are running, and I would end up with an $1800-2000 carbine when I was done - not buying bottom of the line stuff, but a KO upper is $550, Stags et al are more. One thing I like about the 6.8 uppers is that they seem to be piston driven instead of the buffer tube.

So now I am looking at a 7.62x51 (.308) upper. They seem cheaper, and I have brass etc. for reloading. Prices I was seeing for 6.8 cartridges were working out to $1 each, similar to 7.62x51, but I do have some battle packs of the .308.

Decisions, decisions !!!    ??? ???
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: DDMac on March 13, 2008, 05:05:36 AM
Pathfinder, I have asked before elsewhere, but never heard back; how does one put a .308 upper on an AR lower as several people plan, unless they have an AR-10? Mag wells aren't compatable, right? Mac.
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: Bidah on March 13, 2008, 09:46:27 AM
Not to drag this too far..

Overall, the magwell for the .308 is not the issue so much.  The way that the lowers and uppers are cut, are.  The AR-10 uses one style of cut, and the DPMS uses another.  They also use different magazines.  So, the lowers are not cross compatible with the uppers.

Most, if not all of the 6.8/6.5 uppers are compatible with regular AR-15 lowers.

-Bidah
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: DDMac on March 13, 2008, 07:35:36 PM
Thought so, Bidah. It's just that Pathfinder said he was looking at a .308 upper, and I wondered how it could be used without a mated lower. Maybe I misunderstood. Wife says I do that a lot.
Mac.
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: Pathfinder on March 13, 2008, 08:17:13 PM
Thought so, Bidah. It's just that Pathfinder said he was looking at a .308 upper, and I wondered how it could be used without a mated lower. Maybe I misunderstood. Wife says I do that a lot.
Mac.

No, my motto is ready, fire aim. Hell, forget ready and just fire.

I did not think about the magwells, was getting twitchy over the 6.8SPC and was looking for alternatives. I have a DPMS M4 on the A-15 lower. I am also a fan of the .308. I may still go with the 6.8 as a lark, sell it if it gets too $$$$$$. On the other hand, the military could adopt it . . . . .    ::)
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: texcaliber on March 13, 2008, 08:56:56 PM
I like the sound of the AR in 7.62NATO man. The more I research the AR-10 systems there is a ton of "big" cals. options and even the "WSMs" shortmags. It looks like you might of started a need in my brain man.   ;)

Thanks   ;D  Tex
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: someguy on March 13, 2008, 10:00:07 PM
Take this with a grain of salt, but I have heard on fairly good authority that at least two federal agencies have placed significant orders for AR's chambered in 6.8SPC that will be announced/fulfilled in 2008.  Should see more adoption of the cartridge and more surplus ammo.

And no, I don't own one.   ;D  That'll change before long, though.
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: Bidah on March 13, 2008, 10:22:02 PM
Well I have said this before, but if I currently had an AR-15 in 5.56, and did not have the investment in ammo and rifles in .308, then I would get an upper in 6.5/6.8, get some mags, and start buying ammo for it.

Even though I do have the .308's, I am still very much looking to get an upper in one of these calibers, probably two. 

-Bidah
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: Crescendo on March 15, 2008, 10:34:17 AM
+1 to comments above.

If you are looking to play shooting games, or if you are looking for a SD round and believe your engagements are within 150 yards, 5.56 is your round.  In fact for matches, 5.56 will be cheaper and allow you to be faster because of lower recoil.

Here's my quick assessment of the 6.5 Grendel vs the 6.8 SPC debate.  Both hit harder than a 5.56 at all ranges.  Out to 300-400 yards or so, there is very little difference between 6.8 and 6.5...although 6.5 will be just slightly flatter in trajectory.  Beyond 400-500 yards, 6.5 G will take over with more retained velocity and flatter trajectory.  6.8 SPC will have the theoretical edge in reliability because of the slightly more tapered case...probably only will notice that in full auto. 

So, if you want something for short range and/or games -- 5.56
If you want a harder hitting round in an M4/intermediate range set up -- 6.8 SPC
If you want a harder hitting round that will carry out further with 20-24" barrel -- 6.5 Grendel

That said, I just set up a 24" Overwatch upper on a PRS-stocked lower for my DMR rifle -- in 6.5G

KPR - thanx for the nicely stated and informative post.  It appears one of the hazards of forum posting is sorting through individual likes and dislikes before the basic question gets answered.

Thanx again  :D
Title: Re: 6.8mm Remington SPC, 6.5mm Grendel and SSK 6.5mm MPC
Post by: gary4447 on March 15, 2008, 12:39:46 PM
For use against no armor BGs (bad guys)  within 150 yards, do any of the newest and best rounds offer a significant enough advantage over 5.56mm to warrant a new upper? I am assuming they all run on AR platforms.
 Mac.

Probably do not offer a lot over 5.56 inside 200 yards.  Yes they do run on AR platforms, ammo is pricey and not a lot to choose from.  Reloading is the way I am going (less expensive) even though bullet selection if limited.  Hornady and Sierra 110gr SP and Vmax, 115gr hollow point.  Remington 115gr Ultra corelockt soft point and 115gr FMJ.  Uses 270 caliber bullets of 115gr or less.