speedyjerry
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AR replacement
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Yes, years ago. It's the basic rugger A.R. 15. Have more ammo than I can use in this life time
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speedyjerry
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SIG SAUER
https://www.sigsauer.com/spear.html
MCX-SPEAR - SIG SAUER
SIG MCX-SPEAR FEATURES: Civilian version of the U.S. Army’s new XM7 rifle; Available in 7.62x51 and coming soon in 277 SIG FURY; Non-reciprocating side and rear charging handle for maximum flexibility in shooting position; Fully ambidextrous controls including bolt catch and bolt release
What caliber? They are kinda pricey.
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speedyjerry
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Years ago they announced replacing the 5.56 AR / M16 with this 6.8x51 for the military
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speedyjerry
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called US Army M7 6.8x51
I'm generally not an early adopter. The bleeding edge isn't and I don't like being one of the guys who discovers all the bugs.
In this case the jury is still out on both the rifle and the round. In my experience there is never a free lunch. for example, when I shot service rifle competition with an M1A supermatch I'd fire about 5000 rounds per year and change the barrel every other year as with M852 and its 2550 fps velocity you could fire 10,000 rounds before accuracy started to slide. However, with rounds like the 6.5 Creedmoor, the barrel is well past its prime at 1500 rounds. With the 6.8 and the 80,000 psi pressures involved with the military loading, I suspect barrel life will be poor. Not a great feature in a military round.
In this case the jury is still out on both the rifle and the round. In my experience there is never a free lunch. for example, when I shot service rifle competition with an M1A supermatch I'd fire about 5000 rounds per year and change the barrel every other year as with M852 and its 2550 fps velocity you could fire 10,000 rounds before accuracy started to slide. However, with rounds like the 6.5 Creedmoor, the barrel is well past its prime at 1500 rounds. With the 6.8 and the 80,000 psi pressures involved with the military loading, I suspect barrel life will be poor. Not a great feature in a military round.
Sure if you want a $4500 dollar , 12lb. gun with stout recoil firing a barrel burning cartridge that is 6 MOA accurate. That will not see the civilian light of day at $4 s round... what's not to love.
I look forward to the pics when that 80,000psi cartridge blows a gun up.
I look forward to the pics when that 80,000psi cartridge blows a gun up.
LVSteve
Member
You have to wonder who will buy the reduced power ammo with the brass case to feed their uber rifle.
Even chambered in 7.62x51 NATO, I have no interest in it.
HARLEY0
Member
What are you talking about a 50 cal?
6.8 SPC managed to get screwed up only as Remington can. This was supposed to be a great replacement for the 5.56 NATO. Anchors pigs in the south like it's supposed to against 2 legged threats!
I wish I were, instead of the New M7 rifle.
Mike LaNier
Member
It seems they keep re-inventing the wheel here in the gun biz... for example, while the 6.5 Creedmoor is a good cartridge, the increased pressures and barrel life issues don't really make it a great deal better in the long run than the old 6.5 Swede, handloaded with good bullets, in my opinion. The 6.8x 51 pressures are not conducive to good barrel life and accuracy doesn't seem great either, and the 7.62x51 round is pretty accurate; My Ruger #1 in .308 can shoot 7/16th of an inch at 100 yards (I'm not saying I shot that, by the way)... Just a thought.
Dave Haynes
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I look at the newest and greatest and think that in 3 years you can't find a round of ammunition with a Geiger Counter. That is just not the way the ammunition business is headed today. Making all manner of cartridges so they can sit on a shelf waiting for someone to buy them isn't in the plan either...
The M7 is a great rifle at least by what can be read from military brass but not so well liked by troops or field officers after field use testing . Heavy rifle and problem prone seems to be word of mouth now . Plus you carry less ammo .
We have the AR10 that found a place as a DMR / Sniper rifle but it to is a heavy weapon that allows a person to carry less ammo in the field . Now if any one here uses the 308 for hunting there are slightly higher pressure ammo available like Hornady super mag ammo , Not for typical semi auto use ! But I have usedit in a bolt rifle for years hunting . This 308 ammo could make the siggly new high pressure load nut'n special or needed .
Our Military and there bull sheet games they play ! They should have given the 6.5 Grendel a real chance in the field as it is a better all around cartridge than the 5.56 in the AR15 . A barrel swap/ bolt , H buffer and mags is all it takes to convert . . I run a tubbs flat wire buffer spring and H buffer now in my 223 wylde barrel . But why give out troops a lighter AR with a more powerful cartridge than any 5.56 but that's not how the top level military monkeys play with our money and troops lives . But hey that would make for a heck of a lower cost upgrade !
We have the AR10 that found a place as a DMR / Sniper rifle but it to is a heavy weapon that allows a person to carry less ammo in the field . Now if any one here uses the 308 for hunting there are slightly higher pressure ammo available like Hornady super mag ammo , Not for typical semi auto use ! But I have usedit in a bolt rifle for years hunting . This 308 ammo could make the siggly new high pressure load nut'n special or needed .
Our Military and there bull sheet games they play ! They should have given the 6.5 Grendel a real chance in the field as it is a better all around cartridge than the 5.56 in the AR15 . A barrel swap/ bolt , H buffer and mags is all it takes to convert . . I run a tubbs flat wire buffer spring and H buffer now in my 223 wylde barrel . But why give out troops a lighter AR with a more powerful cartridge than any 5.56 but that's not how the top level military monkeys play with our money and troops lives . But hey that would make for a heck of a lower cost upgrade !
I have always thought the Grendel was never given the credit it deserves -- I also believe it's a better choice than a 5.56. I have made several of them myself, a quick barrel and bolt swap, or just put together a dedicated upper, and correct magazine. As the saying goes - it punches well above it's weight class.
Historically speaking the majority of the problems with the original M193 development and related XM-16 development problems trace back to Remington:6.8 SPC managed to get screwed up only as Remington can. This was supposed to be a great replacement for the 5.56 NATO. Anchors pigs in the south like it's supposed to against 2 legged threats!
-They created the penetration, velocity and pressure problems by replacing the Stoner/Sierra designed 55 gr seven secant ogive high BC projectile, with their own shorter 55 gr five tangent ogive projectile. This Remington projectile lost 175 fps versus the original at the 500 yard penetration distance and thus failed to penetrate.
- That led to the need to develop a powder that would increase the muzzle velocity to make up that velocity loss at 500 yards.
- Which led to the pressure issues, and waivers: as well as
- The powder fouling issues.
The British had it right in 1948 when they proposed the .270 British for the FAL, based on extensive research indicating the ideal intermediate round should have a diameter of roughly 7mm, a weight of 140 grains and a muzzle velocity of around 2400 fps.
Unfortunately, the US insisted that the new NATO standard round have essentially .30-06 ballistics ( roughly a 150 gr bullet at 2800 fps), with the only advance being the 1/2" shorter case. And of course almost as soon as the 7.62x51 NATO was adopted, the US started developing the 5.56x45 as it recognized the 7.62x51 was unsuitable for select fire use in an infantry rifle.
The 6.5 Grendel offered very similar performance to the .280 British with a 130 gr bullet at 2510 fps, while the 6.8 SPC offered similar performance with a 120 gr bullet at 2460 fps.
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And yet once, again the US military screwed it up by adopting the .277 Fury / 6.8 x 51 Common Cartridge, using a case with 7.62x51 length and case head dimensions launching a 135 gr bullet at 3000 fps, again ignoring the issues with excessive recoil in a select fire weapon that really should be firing an intermediate cartridge. And then doubling down on it with an expensive to produce hybrid case to manage excessively high pressure in what will be a barrel burner cartridge.
