[tdoyka]

This is a absolute nightmare. There is nothing wrong with the 5.56 as a combat cartridge as you can see in the Ukraine. I carried the M4 as a contractor in Iraq and always carried 400 rounds of ammo and that is something I could not do with this abortion. If I was Grizzly hunting sure but for people massive over kill and too heavy.

mostly they use 5.45x39 in their ak's, but they have 7.62x39 somewhere.

i never used a M4, it was M16A1 or A2. the 5.56 is a good 300 meters/yards and under combat cartridge. but once you over 325 - 350 meters/yards, it has a problem or problemS. the 7.62x39 and the 5.34x39 have the same problems. i felt that i was under gunned with 5.56, probably because i was a hunter.

back in my day.....they didn't have the cartridges that they have now....6.5 Grendel or 6.8 SPC or.....whatever. (wildcats are not included) we had the 5.56x45 and the 7.62s51 and 50BMG. in my mind, the 5.56 and 62gr M855 was a groundhog gun. fun to shoot but it just wasn't fer me. the 7.62x51 however, was "the man's cartridge". but it was only available in the M60 machine gun and it weighed about 20 lbs. "the Pig" was a good name for it, heavy, loud and has a voracious appetite for bullets. i luved to shoot it, but hated to carry it.

NATO has finally got its act together (finally has 5.56x45 for all nations) and then we do this poop, 277 Fury and oh, by the way, the old rifles? get rid of them. buy an ar 10 action and go from there. you've got to kidding me? do a 2 piece body case if you HAVE to and do a new barrel for 6.5 Grendel or other 5.56 cartridge length.

yes, i feel the 5.56 is under gunned at above 300 meters/yards. but there is a range of cartridges and length (5.56) to go after.

 

[Legolas]

Rickyerby, thanks for speaking up. We get rapped up in expressing our opinions about a new rifle and cartridge, or we should use a classic cartridge, or it’s a waste of taxpayer money to feed the arms industry. Maybe nothing we write on this forum will matter, but we are citizens and we could write our congressional representatives. The tragic stories of the early failures of the M16, where American soldiers were killed because their new weapons jammed, were brought to light when American soldiers wrote to their congressional representatives.

I pray to God that our leaders are blessed with wisdom. I want American soldiers to be well armed and well supplied, and effective at short and long range. During WW2, squads and platoons had a mixture of M1 Garands—M1 carbines—Thompson submachine guns, and ammunition supply had to be complicated. Maybe a squad could have a mix of 5.56 and 6.8 weapons. I don’t know if this would be practical or wise.

Something I have thought about…could drones be used for resupply? Could drones drop off a 200 or 300 or 500 pound package into a hot zone situation?… in a situation where the truck or helicopter was not available? Would you trust your life to that kind of supply line? Could thousands of drones supply scattered small units?

 

[MainerUSNR]

we have some great cartridges in the ar-15, like 6.5 Grendel, 6.8 Wolverine, 6.8 SPC, heck i even go with the 6 ARC (didn't the gummint already had this?)....but the gummint says ar-10 in 6.8x51(277 Fury).

i'm going from memory(don't trust it. i don't!!!), the gummint wants to have a heavier platform, 20 - 25 rnds per magazine, heavier cartridge, semi to full auto, 2 piece cartridge body, it "kicks" the bejeezus out of ya. this is all for the 3000fps+ and it penetrates body armor? ahhhhhhhhh...yeah, go ahead and buy it. and find out that Army/Marines qualification scores go down.

this is just me, but wouldn't the gummint do a 2 piece case in 6.5 Grendel or 6.8 SPC? then they could do ar15 type weapon with 80,000 psi or CUP or whatever. DARPA, i'm talking to you.

i like the idea of 6.8x51 for the heavy machine gun, it could take the 7.62x51 off the map and the 5.56 MG(m240 and 249) and throw them away.

hmmm....maybe i don't want 6.8x51. 80,000psi is alot pressure and can it take it? the barrel life, i mean. i have never done it, but the m60 with 7.62x51 could heat the barrel red hot. thats why we trained with 6 - 9 rounds (a short burst). i think it somewhere around 250 rounds that you had to change the barrel? but we never did, we go 750 - 1000 rounds before we changed the barrel (makes you glad to use and carry an asbestos gloves ), but that was with short bursts. a long burst was really, really frowned on by our sergeants. not that i did it or anything...............

oh well, NMP.

I agree with tdoyka, I thought the same things. I have been reloading for quite some time and there is no magic going on here in physics in the 277 Fury or .277 X 51, higher pressure will eat barrels. And the new M5 is heavier than the M4. Like tdoyka says why didn't they take the 6.5 Grendel or 6.8 SPC and give them the "Magic 80,000 PSI Case"? The only would need to change the bolts and barrels. Assuming we could get an additional 200 fps out of a suped up Grendel in a 16 inch barrel we would be looking at 2,700 fps with a 125 grain fmj bullet and about 1,100 fps at a 1000 yards, 399 fpe to boot. Comparing those results to a 5.56 with 62 grain bullets (607 fps, 51 fpe, from Shooter's Calculator) would give the Grendel the advantage of about 400fps and 350+ fpe.

 

[tuckerbob47]

Why a 277? How about the 270 we already have. It's accurate, flat shooting and hits hard..I interviewed a lot of WW II, veterans and Vietnam Veterans. The WW Ii Soldiers never complained about carrying 3006 ammo, or their M-1. The Vietnam veterans said they wished they had an M-1. They hated the 223 cartridge.

 

[MikeG]

Well, one thing that did occur to me is overlap with civillian / commercial chamberings, if this extreme high pressure version comes to pass. There are doubtless a few wildcats around for .308 necked down to .270, but a lot fewer wildcat rifles for high-pressure rounds to find their way into than some poplular off-the-shelf cartridge.

The 'regular' .270 Win is probably out, if for no other reason than the shorter case gives a shorter action, and you're carrying less brass around as well (or whatever else the cartridge case is made out of). Not a huge consideration for most hunting but most deer hunters aren't wandering the woods with several hundred rounds..... at least, you'd think not!

But, a smaller diameter case also gives less brass to tote around, per round. So, basing something on the 7.62x39 would make more sense if ammo weight is a consideration. However, I don't expect the military to ever adopt anything on the soviet design, as a point of pride. Why they didn't gin up this new cartridge on the 6.5mm bore size is beyond me, if weight is the least consideration. Get the same penetration out of a smaller diameter bullet, but that smaller diameter bullet will weigh less. Or go 6mm, .25 cal, etc.

Maybe they read too much Jack O'Connor and decided that the .270 bore size is magic!

 

[CoyoteJoe]

I haven't trusted U.S. Ordinance Dpt. since they swapped the Spencer repeater for the Trap Door Springfield, not even a very good single shot . Custer is still smarting over that one.

 

[Don Fischer]

Why a 277? How about the 270 we already have. It's accurate, flat shooting and hits hard..I interviewed a lot of WW II, veterans and Vietnam Veterans. The WW Ii Soldiers never complained about carrying 3006 ammo, or their M-1. The Vietnam veterans said they wished they had an M-1. They hated the 223 cartridge.

Thing about the reg 270 is the same problem with every other cartridge except the 5.56. Due to weight and space you can carry a lot more 5.56 than anything else. If your in a fight one round can mean the difference between life and death. Drawback of all American military cartridges is the FMJ bullet. Just doesn't do the same damage as soft point bullets with a poorly place shot. In war shooting comes much faster generally and shot placement is often not all the great. Especially in full auto in which case number of hit's on a target mean a lot. Only place I could think of precision shooting would matter is sniping. I think in war, every cartridge would have it's faults.

 

[RIDE-RED 350r]

Tried to delete comment

 

[tdoyka]

my biggest concern is what are you going to do whenever someone goes full auto on the rifle. shoot at the sky after 2 rounds? you do know that it "kicks"? the armed forces are going to see the qualifications scores go way down. Special Forces, Delta, Seals are the first up to get it and they will tell the gummit to shove it. the recoil, esp at full auto, should be enough to disqualify the rifle. you think that the gummint would remember the SCAR rifle. (5.56x45 and 7.62x51 and the 6.5 Creedmoor are chambered in the SCAR, the 7.62x39 and ak magazine are chambered to the SCAR also) i think that the Special Forces are the last ones left that uses the SCAR. the rifle was supposed to be THE GUN for the armed forces, go figure.

oh, i know!!! i'll develop a new cartridge and a new rifle....oh, i'll do the optic sights too. here's the best part. i'll tell NATO that they have buy the the new and improved rifle and cartridge.

ahhh.....yeah. do you know that pigs can fly and do hand stands under water?

 

[Legolas]

MikeG said, “Why they didn’t gin up this new cartridge on the 6.5mm bore size is beyond me…?”
Many of you have asked this question.

I did some crude calculations trying to get a feel for the ratio of case capacity to bore capacity, and how much force could be applied to the base of bullets in different calibers. Using Pi times radius squared = area of circle (caliber), I calculated for 6mm, 6.5mm and 6.8mm. Using 645.16 sq mm = one sq inch, I converted and calculated pounds of pressure on the bases of the various bullets. A bullet is like a piston in a hydraulic cylinder. The cylinder is like the barrel, and the hydraulic fluid is the high pressure burning gas from gunpowder. The hydraulic fluid applies pressure on the piston (usually 1800 psi in common farm equipment), and the total working pressure is 1800psi X whatever the square inchs on the diameter/caliber face of the piston happens to be.

6mm caliber is 28.26 square mm=0.0438 sq inch
6.5mm is 33.16 square mm=0.0514 sq inch
6.8mm is 36.30 square mm=0.0563 sq inch

6mm-0.0438 sq in X 60,000psi = 2628 # pressure
6.5mm-0.0514 sq in X 60,000psi = 3084 # pressure
6.8mm-0.0536 sq in X 60,000psi = 3378 # pressure
7.62mm-0.0706 sq in X 60,000psi = 4239 # pressure

6.8mm-0.0536 sq in X 80,000psi = 4504 # pressure

So the 6.5mm bullet at 60,000psi will have 3084 lbs of pressure applied to the base of the bullet. A 6.8mm bullet at 80,000psi will have 4504 lbs of pressure applied to the base of the bullet.

The Nosler book shows the following:
.243 Winchester 100gr bullet up to 3100fps
.260 Remington 100gr bullet up to 3300fps
.308 Winchester 110gr bullet up to 3300fps

I think the Army made a compromise. They chose to push for high velocity over aerodynamics and sectional density.
……………………………

I did a little internet searching after the discussion about Sherman tanks and German tanks.

The Sherman’s 75mm gun fired a 20 lb AP shell at 2030fps, a 13.6 lb AP shell at 2850fps, and a 15 lb high explosive shell for infantry support at 1520fps. This gun could destroy all German mark 4 tanks and Stugg 3 armored guns (front facing guns with no turret), and penetrate the side armor of mark 5 Panthers. The mark 4 was mass produced throughout the war and was a peer to the Sherman.

The British 17 pounder “firefly” gun put in some Shermans, fired an AP shell at 2900fps, and a primitive not very accurate discarding sabot round at 3920fps. It may have gotten the name “firefly” because it burned a lot of powder.

The 90mm gun on the US M36 tank destroyers fired a 24 lb AP shell at 2800fps, and the much more effective hi velocity armor piercing (HVAP) 17 lb shell at 3300fps. This gun was very effective against the Tiger tanks.

The German Tiger 1 carried the basic 88mm gun (KW 36) fired a 22 lb shell at 2600fps, and a 16 lb HVAP shell at 3100fps.

The Tiger 2 (King Tiger) had a longer barrel and was chambered for a magnum shell case holding more powder than the standard 88mm KW 36. The King Tiger gun was designated KW 43, and it fired a 16 lb shell at 3700fps. It was designed to destroy large numbers of Soviet tanks.

It seems that with all these guns, the lighter weight/higher velocity shells were the most effective at penetrating armor. I think the Army chose 6.8 over 6.5 because the larger 6.8 bore could PUSH a medium weight shell to effective armor piercing velocity.

 

[Pudfark]

I told myself, I wasn't gonna offer an opinion in this thread, again. Yet, here I am. Asking questions? Who determines who is an expert? There likely isn't a person here, who hasn't met a 'so called' expurt? I've erred on the side of caution all my life, some would say? I've always been a believer in the fella with the muddy boots, who has experience putting metal on meat, over the guy with the slide rule and the pocket protector, am I wrong? I don't mean to provoke at all, I do believe that a good part of this discussion lacks defined language? I will now bow out again.

 

[recoil junky]

I gotta agree 1000% with pudfark.

RJ

 

[JBelk]

I wish I could publish the MH Walker note books. The inventor of the 222 was MAD about the .223/5.56 and had nothing at all good to say about the 'Gov guys that never heard of Newton and seemed intent on doing the impossible by throwing more money at it.'
Mike Walker was NOT impressed by procurement guys at all and wrote cryptic notes that are entertaining to one that loves ballistics. "Where is a 10K altitude range? That'll work!"
They chronographed some loads in Leadville CO. Instant magic!! Instant trajectory repair. Write it down!

 

[tdoyka]

ELITE BONDED POLYMER TIPPED 277 SIG FURY HYBRID (sigsauer.com)

ELITE BALL FMJ 277 SIG FURY (sigsauer.com)

if you notice both of rounds and the fps and out of WHAT barrel, do you really think that the 13" barrel is going to 3000fps? the round can't make 3000fps with a 16" barrel and Sig is telling me that 3000fps out of 13" barrel is real?

 

[tdoyka]

I wish I could publish the MH Walker note books. The inventor of the 222 was MAD about the .223/5.56 and had nothing at all good to say about the 'Gov guys that never heard of Newton and seemed intent on doing the impossible by throwing more money at it.'
Mike Walker was NOT impressed by procurement guys at all and wrote cryptic notes that are entertaining to one that loves ballistics. "Where is a 10K altitude range? That'll work!"
They chronographed some loads in Leadville CO. Instant magic!! Instant trajectory repair. Write it down!

thats a caliber that used accuracy as its middle name, 222 remington. i had a savage m325 in 222 rem and it was exceedingly accurate. i got it second or third or.... hand and the only thing i did was to exchange the scope, 6x Swift (when they had an over-the-counter warranty). i shot at woodchucks, red and grey foxes, crows, rocks, targets, soda bottles......at ranges out to 300 yards, i did however shoot a groundhog at 330-350 yards (didn't have a laser range finder thingy back then) the trigger pull was horrible, but after i shot it several times, i got used to it. 50gr Hornady sp with a max load of h322 would go under 1/4" at 100 yards(5 shots/bench). i must have shot 6000-7000 rounds thru her (3 - 4 years). i don't know the round count because i bought it 2nd or 3rd hand. anyway, i took it to my gunsmith (RIP) and he bore scoped it and he said, what i could have known, that barrel was fried and some spots the rifling was non-existent.

so i did the most stupidest thing i could do, i sold her and bought either a rem m700 or was it a savage 110 in 223 rem. stupid, stupid, STUPID!!!! i should have rebarreled her to the 222 rem.

i could not do 1/4" groups, heck, i hard time doing 1" groups. IMR, Hodgon, Hornady, Speer, Sierria....didn't matter what i tried, i had a hard time doing a 1" group. a couple of years later, i sold her.

i have a 20 Vartarg right now that can do .1 - .2" at 100 yards(5 or 10 shots/bench) with careful handloads. sloppy reloads is around 1/2" at 100 yards. i sold all of my varmint calibers off (expect 22rimfires) expect the 20 VT. a 222 rem, however, has a space in my safe, ready and able.

 

[JWSmith1959]

I've been a hunter (and a guy with a slide-rule) most of my life. I happened to be born in that 4-year period where I wasn't required to register for the Draft. (late 59 to late 63). I missed all the parties, so to speak so I have no dog in this hunt, except for my nephews and grandsons. The teeny-tiny branch of the Smith name in my family (as far as I know) is gone forever. I was the last male to give offspring.

I have no issue with a .277 cartridge and think it is a good idea. It's not like whatever "projectile" the military chooses will be a common one readily available to us to begin with. I personally would have gone with the 6.5 group.... which is 13 thousandths smaller....noted. I'll just have to trust our higher ups to make the right choice. If they don't we are already in a bad place.

 

[Pudfark]

Interesting choice the Israelis considered? Calibers 5.56, 9mm and 5.45 in the 'Carmel' battle rifle, along with the Tavor 7 which comes in a 7.62 caliber.
Is the ‘Carmel’ the future of Israeli rifles?

Sorta interesting to me, standard cartridges all. No new off the wall cartridge design? Some folks might construe that to be...?

 

[Legolas]

In post #74, Tdoyka provided links to two Sig ammunition pages. One is for a high pressure load with a 150gr bullet that looks like a Nosler AccuBond. They claim 2830fps from a 16 in barrel, and 3120fps from a 24 in barrel. So regular .270 Winchester performance from a 16 in, and .270 WSM or Weatherby performance from a 24 in. Sig has an advertisement showing a bolt action chassis type rifle with a suppressor. I think one would need a suppressor or hearing protection to hunt with an 80,000psi cartridge. Ammunition is $80 a box.

Is the suppressor on the M5 and M250 for hearing protection of soldiers, or to hide their position by not giving out raw gunfire noise? If the Chinese are ever the adversary, they will have thermal vision sights and binoculars, and those hot suppressors will look like a big bright bullseye in a Chinese thermal vision sight.

The M250 weighs 16.2 lbs, so about the same weight as M249 SAW, but ammunition will probably weigh 2.5 times as much as 5.56.

The M5 with 16 or 20 inch barrels will weigh close to 9 lbs, with 30 round magazine about 10.5 lbs, and with scope and electronic module about 12.5 lbs at least.

 

[roseman]

Another solution searching for a problem.
But the military industrial complex must be lubricated periodically.

 

[Darkker]

🤦
Anyone who followed the links and researched the actual sources, knows that the requirement for the 277 ammo was to weigh less than the 7.62 NATO. Meaning they know that the ammo doesn't weigh anything like 2.5 times what the 5.56 does... Similarly, they would have researched the XM157 contract. Meaning they also know the new optic weighs less than the currently issued mess.

Here are some more links, that some will also ignore.

XM157 discussion, from the source.

Study on hit probability of the Garand.

Study on hit probability of the M16 family with optics.