AR platform in FN 5.7, 6.5 Grendal or 6.8 SPC???

J

joeshredd

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May 8, 2002
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Okay, we've seen several threads lately on what's the best AR, best magazines, etc...

My question is which of the above mentioned calibers offers the best advantage?

I just got a lower and I'm trying to decide what kind of upper to work with.

I've toyed with the idea of getting the 5.7, as it can mount a magazine on top, which is flush mounted and is gas piston operated (IIRC!)

Someone just posted a link to Alexander Arms and they make uppers in 6.5 Grendal that can apparently outshoot my AR-10(T) at 1200 yards.. Not that I can shoot out to 1200 yards, but it's a nice little factoid...

However, another buddy of mine mentioned that the 6.8 SPC (IIRC), developed by Remington (?) was a superior round to either...

I like the idea of gas piston operation over the traditional AR system, and I have that in my SIG 556. I'm also not likely to reload, so the odd caliber may make for difficulty in obtaining ammo...

And I'm sure there are other considerations I haven't thought of...

Any experiences, preferences, specific links, etc, y'all may have would be greatly appreciated in this little quest of mine...

Thanks Guys!!!!
 
I guess it depends on how you're going to deploy it. The 5.7 is an intermediate cartridge while the 6.8 is a true rifle round (I'm not familiar with the Grendal offering) that will work very well on the AR platform - it was designed as a more powerful replacement for the 5.56.

If you want to have an all-around "go to" rifle for any situation I'd go with the 6.8.

With either round resupply may be difficult and expensive. Good luck!
 
Thanks so far...

Voodoo... I have an AR 10 "T" in .308... Also a CETME and an Ishapore rebuild in .308... Love them, but if the Grendal can outshoot 'em accurately, well, it's just one more thing for me to consider... I like the idea of the 5.7 - no mag protruding downward, or, insert a mag w/o the spring and follower and use it to catch the brass; also, it's a gas piston...

Dang - decisions, decisions!! :confused: :eek: :D
 
Seeing as you don't plan on reloading I would rule out the 6.5 and the 6.8 rounds. No cheap ammo available and if taxes on ammo are created by Nobama as expected it will be very expensive if you don't stock up now. The 5.7X28 reminds me a lot of the 30 Carbine...a hot pistol round and not suited for long range. If you don't mind a 300 yard limit it would work well...of course the uppers are pricey.

If I was building up another AR from scratch and wanted to use something other than .223 (I already have a .30 caliber AR) I think I would go with the 5.45X39. The 5.45 AR uppers are average in pricing in this caliber and buying 5000 rounds of ammo won't break you either, it is the best priced surplus ammo available today.

The 6.5 MPC also merits consideration.

For accuracy I would give the nod to the 6.5 Grendel.
 
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Rat Finkenstein said:
I could be wrong, but I think it is delayed blowback.
the traditional AR is direct impingement.
Click to expand...

I believe so as well. Basically the 5.7 works like it would in the pistol.

=====

To the original question, from what I read and remember the 6.5 Grendel was superior for shooting at range and ballistically vs the 6.8. I believe the military has favored the 6.8 for logistical reasons mainly the magazines can be built from regular m16 mags while the 6.5 takes a mag you have to make from scratch. So if memory serves me, 6.5 is better for the individual.

However as noted ammo is pricey and no surplus available for cheap aquisition.

Ironically both the 6.5 and 6.8 have a similar ballistic to the original intermediate cartridge that the British introduced when NATO was trying to find a new standard cartridge. The US kinda strongarmed NATO for the .308 and found they couldn't make it work well in a auto M-14 and through a long history of a few short years before and during Viet Nam came up with the .223 Now forty plus odd years later we are wanting a further lethal reach for our riflemen so are looking at the 6.5 and 6.8

Now if any real gun guru finds errors in the above, please point them out but please be nice. :)
 
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The 5.4x39 is a great round and CHEAP!! The 6.8 will have better availability then the Grendel but if the military dosnt really adopt it which is a rumor I have heard it may die out. As for the 5.7x28 I imagine while fun to shoot it is expensive and it has a bad and undeserved reputation among the Liberals as a "Cop Killer" because of its penatration and it could be the victim of another ban. Rounds like .308 arnt going anywhere and can be bought inexpensively almost anywhere in the world and it isn't going anywhere. Just my $.02
 
The 6.8SPC and 6.5G both work very well at close range, especially if you have an SBR. At longer ranges, the 6.5G holds an edge if you are using a DMR rifle. The 458 Socom and 50 Beowulf are both solid thumpers if you are shooting at close to intermediate ranges.

The FN 5.7 seems to hold the most promise if you are using an M-16. I don't really understand it in an AR-15. The FN 5.7 really shines on a submachine gun so, I don't ever see owning one with a 16 inch barrel. I have an SBR and M-16 that would work well with an AR-57 upper.

Calibers seem to bring out a lot of machismo, bragging, and boasting in a lot of people. Fact of the matter is, in a 16 inch AR-15 they all work pretty good for what most people will use them for if you stick to rifle calibers. If you are going to hunt bears, elk, etc. a large caliber would be better. If you are standing at the 600 yard line at a DCM range, you are going to like the 6.5G or some heavy 5.56 best.

Overall, its best to clearly identify what you will use the rifle for and get the caliber that matches that use best. Most ammo costs pretty close to everything else and when you factor in most people aren't shooting several hundred rounds a week, a $1 or $2 per box isn't a big financial burden or benefit.

I don't see much cheap 5.56 (or .223 for that matter either), get a pretty good deal on Wolf 6.5G, don't shoot enough 458 Socom to be overly concerned with cost, etc. so I buy a good supply of whatever I'm in the mood for and enjoy my rifles.

Heck, I'm getting into wildcats now with my first 338/06AI in work right now and I just bought another 30-06 rifle for either a 280AI or 411Hawk. These make my other "evil black rifles" looks cheap in comparison unless I'm dumping Beta mags. :D
 
My specialty ARs are just that...specialty pieces. I don't blast a bunch of ammo through my suppressed 300 Whisper...except in competition... and my 10 inch shorty was designed for entry gun work, I tend to shoot full length barrels in public rather than spending valuable range time answering questions and being told ..." boy that thar thang is e-legal!". I did stock up on ammo before the election, Dad and I put up about 3 grand worth in various calibers and I already had a couple of cases of 308, .223, and 8mm. I have plenty of components for my various wildcats and oddball calibers so no worries there.

Didn't realize Wolf was making the 6.5 Grendel...good deal there as I see ammoman still has some at 250 a case shipped. Another reason to lean that way for a new AR but I wouldn't wait too long...
 
Thanks guys...

I've spent some time on AR15.com, and found out that 6.5 and 6.8 have their own .coms, too!!! :eek: :D

I don't yet have a specific use for this as I already have AK's, a CETME, an Enfield in .303 and .308 and an AR-10T... But, I just got a good AR lower and I was toying with the idea of an AR-style piece that doesn't have the same operating system as the AR does... I was really leaning towards the 5.7 - heck, 4 magazines in almost the same size as an MP5's and I've got 200 rounds of ammo in a nice easy to use and maintain package... But, as I've read more, and talked w/others, the 6.5 G is sounding nice enough that I may sell the AR-10 and get the Alexander Arms upper in a 16" version for both distance and potential hunting applications... ballistics look awesome on the 6.5 :eek: ...

Dang, decisions are driving me crazy!!! :D
 
i think i am gonna just stick with the std 5.56 in AR's myself, if i want something more powerfull i have an AK, or could get something like a SOCOM or SOCOM2, the exotic calibres arent gonna get adopted imho, not right now anyway, and if not they are gonna die out, i wouldnt want a 5.7 AR any more than i want a 9MM AR, probably less lol, imho the 5.7 is really only at its best in a pistol, with AP rounds, in a military scenario where everyone has armor on, i see no reason to go with 5.7 in an AR.

the new heavy 5.56 supposedly works pretty good even in M4's.
 
If you do end up getting a 5.7 check out extreme ammunition and stock up (there wait is 4-6 weeks now). You'll find no better ammo available and all of there ammunition has higher velocities and AP abilities compared to the now banned SS190. There ammo is top notch and extremely accurate as well. Other than that the other 2 rounds available commercially are best used for plinking or for varmints. Oh, and stock up on mags....
 
Absintheur said:
... and my 10 inch shorty was designed for entry gun work, I tend to shoot full length barrels in public rather than spending valuable range time answering questions and being told ..." boy that thar thang is e-legal!".
Click to expand...

One of the benefits of living in Arizona is the large Class 3 community. Law Enforcement sometimes is a little miss informed but, I don't run into too many outright idiots. My 10.5 inch uppers are for fun range days. Back home, I use something longer because I'm not doing CQB exercises in a shoot house. Adding a suppressor adds enough "nose" to kill the short barrel benefits anyway.
 
I would buy some gold before the supply gets any shorter.
Spot price is low eights but actual pricing will be about a grand for an One Ounce coin landed.
 
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