.277 Fury and 5.56 Nato supporting data from US 1950-1966 Study

[Jimla]

Interesting 1950-1966 study:

Tested 4 Calibers: .30 .27 .24 and .21 and 3 powder loads 100%, 80%, 60% of a 30-06 cartridge.

The Charts shows the positive results moving from the 30-06 cartridge to .224 caliber for 400 yard combat with only 60% gun powder. Both better Hit Probability and Wounding Power.

The Charts shows the positive results moving from the 30-06 cartridge to .277 Fury at all combat ranges, they had to increase the pressure to get 30-06 performance out of a 308 size case with a short barrel. Both better Hit Probability and Wounding Power at all ranges.

A 6.5 Grendel like load was in the study but it did poorly relative to 30-06 cartridge. This may be why 6.5 Grendel and 6.8 SPC ammo never was a final solution to the US military. The lowest line on both charts was like AK 47 like cartridge.

I marked the charts with load similar to .277 Fury, 270 Win, .25-06 Rem, 30-06, .224 Valkyrie, and 6.5 Grendel.

Relative Wounding Power.jpgRelative Hit Probability.jpg

https://www.everydaymarksman.co/resources/an-effectiveness-study-of-the-infantry-rifle/

[danm]

Interesting 1950-1966 study:

Tested 4 Calibers: .30 .27 .24 and .21 and 3 powder loads 100%, 80%, 60% of a 30-06 cartridge.

The Charts shows the positive results moving from the 30-06 cartridge to .224 caliber for 400 yard combat with only 60% gun powder. Both better Hit Probability and Wounding Power.

The Charts shows the positive results moving from the 30-06 cartridge to .277 Fury at all combat ranges, they had to increase the pressure to get 30-06 performance out of a 308 size case with a short barrel. Both better Hit Probability and Wounding Power at all ranges.

A 6.5 Grendel like load was in the study but it did poorly relative to 30-06 cartridge. This may be why 6.5 Grendel and 6.8 SPC ammo never was a final solution to the US military. The lowest line on both charts was like AK 47 like cartridge.

I marked the charts with load similar to .277 Fury, 270 Win, .25-06 Rem, 30-06, .224 Valkyrie, and 6.5 Grendel.

[ATTACH=CONFIG]18875[/ATTACH][ATTACH=CONFIG]18874[/ATTACH]

https://www.everydaymarksman.co/reso...nfantry-rifle/

Nice work! Wonder why the 6ARC was adopted by some special units considering this chart???

[Fess]

Nice work! Wonder why the 6ARC was adopted by some special units considering this chart???

[BluntForceTrauma]

Technology has changed the assumptions made in these earlier studies. They were based on iron sights and old models of "wounding power". The introduction states: "For the purposes of the study, Hall discounted any effects of gyroscopic instability that induced tumbling or fragmentation."

I remember reading a test from WW2 era. Author noted that a .30-06 could NOT penetrate 12 inches of oak at 50 yards, but at 200 yards it could penetrate about 36". At the time, they considered this kind of penetration a good thing.

They first looked at 6.5 Grendel as the most obvious solution to their problem, but developed 6ARC because it had better external ballistics than 6.5 Grendel.

It is also claimed in Hornady's YouTube podcast at 15:14 HERE that the 6ARC has BETTER wound ballistics than 7.62x51.

[LRRPF52]

[BluntForceTrauma]

Weren't the Germans trying to solve the "fleeting target" problem with the high cyclic rate of MG34 and MG42?

Fleeting target issue is a thing. In "With the Old Breed: At Peleliu and Okinawa" Sledge tells the story on Okinawa they had to run back and forth from one mound to another, and every time they were briefly exposed in the gap a Japanese machine gun opened up on them, and it was causing problems. They solved it by parking a Sherman in the gap for cover and ran behind it.

Pretty sure the increased recoil of 6.8 NGSW is not gonna help the fleeting target problem despite fancy sights. Maybe you only get one shot before recovering your sight picture while a milder cartridge gets three? Don't know....

[LRRPF52]

MGs had high cyclic rate, while the Sturmgewehr had really low cyclic rate.

FG42 also had low cyclic rate, which is why the M60 had low cyclic rate. M60 is an FG42 with MG42 feed tray mechanism and cover basically.

With MP44 Sturmgewehr on automatic mode, you can maintain really nice rate of fire on-target on runners within short distances because it has low cyclic rate and constant recoil operating principle.

You can easily break single shots on automatic mode too since the cyclic is so slow.

Jim Sullivan developed some different components to try to make the AR-15 more like that, with the Rate Reducing Buffer, but I like the normal cyclic rate on semi in the AR since recovery is quite easy for a trained shooter.

[lazyengineer]

These are super blurry and hard to read, so I'm not sure what I'm looking at?

[Jimla]

These are super blurry and hard to read, so I'm not sure what I'm looking at?

Limit on max upload size on this website, that why it blurry. You can see better images on the original site with article.

https://www.everydaymarksman.co/resources/an-effectiveness-study-of-the-infantry-rifle/

Tested 4 Calibers: .30 .27 .24 and .21 and 3 powder loads 100%, 80%, 60% of a 30-06 cartridge.
.30 with 100% Powder is like a 30-06
.27 with 100% Powder is like a 270 Win or 277 Fury
.24 with 100% Powder is like a 25-08 Rem
.21 with 100% Wildcat 22-08
.30 with 80% Powder is like a 308
.27 with 80% Powder is like a 6.5 Creedmore
.24 with 80% Powder is like a 243 Win
.21 with 80% Powder is like a .22-250 Remington
.30 with 60% powder is like a AK 47
.27 with 60% powder is like a 6.5 Grendel
.24 with 60% powder is like a 6mm ARC
.21 with 60% powder is like a 244 Valkyrie

[BluntForceTrauma]

LR, so it sounds like the "fleeting target" thing is not a thing anybody's tried to solve with technology. If high cyclic rates were the solution, you'd think everybody would have done it.

[Old Bob]

Hitting a fleeting target... It's like the question asked by a musician not familiar with NYC: "How do I get to Carnegie Hall?"

The answer, "Practice man, practice."

[Fess]

It is not uncommon to get only one shot at a fleeting target. That is why high velocity and short flight time tend to do better in those tests. Features planned for a future iteration of the wonder-optic involve identifying the target and sending the round downrange only when the fire-control-system says it will hit. There has also been considerable work done on chassis systems that will slightly yaw the barrel as the trigger is pulled to assure a hit. I am not at all certain that the barrel-yaw system will ever get light and compact enough to work in a general purpose firearm, though.