LRRPF52 Wrote:My problem with General Purpose Cartridges is that they aren't well-suited for important engagement scenarios, and soldier's load considerations, particularly when you understand the relationship between soldier's load and combat endurance.

If there is one candidate for a GPC, the Grendel is the cartridge to beat, but you would still need 2 or 3 different loads for it ideally:

An assault rifle load with a lighter projectile of 100gr or less, with high velocity

A Light Machine Gun Load pushing a high BC FMJBT of 130gr at 2600fps or more

A DM/Sniper load of a 123gr BTHP pushed at 2600fps

That kinda makes the assault rifle load questionable in comparison to the 5.56, since 5.56 is an awesome little cartridge that I can carry a ton of, resulting in the extended fighting duration of my unit.

7.62 NATO should be the cartridge that is phased out, and replaced with a 6.5mm LMG and DM/SASS cartridge.

Tony Williams Wrote:I saw, not long ago, the results of an analysis done of various rifle calibres. I can't provide more details of the circumstances, other than to say it was in a military context. The study (a paper exercise using various ballistic and other performance software available to the military) compared the performance of the 6.5 Grendel (123 grain OTM), 6.8 Rem (115 grain OTM), 7.62mm M80, 5.56mm M855 and 5.56mm MK262. It wasn't intended to be a particularly exhaustive analysis, but I thought you might like the outcome:

In external ballistics, the rounds fell into three groups: the M855 and 6.8mm Rem were very similar; the M80 and MK262 were also very similar, and much better than the first pair; the Grendel was by itself, waaaay out in front on every metric (including calculated barrier penetration). The work included the effects of wind drift as shown on some typical "advancing man" targets at 300m. I didn't note the wind speed, but a shot aimed centre-mass would have hit very close to centre mass with the Grendel, and just clipped the edge of the target with M855.

None of this will come as any surprise to anyone on this forum, of course, but it was nice to see this coming from a military source.

I did point out that replicating these performances with copper+steel bullets as currently favoured by the US Army would be difficult (probably impossible with MK262), due to the considerable extra length required.

LRRPF52 Wrote:...Again, when someone finally makes a Grendel LMG,....

HANKA Wrote:... and 911 perpetrators.

Nukes Wrote:Is this the paper you seek?
http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA512331&Location=U2&doc=GetTRDoc.pdf

Nukes Wrote:Has anyone seen an Ameli for sale? I have not seen one or seen one for sale since the mid-80's. I think it would be a great platform for the 6.5G LMG being proposed.

hellcat370 Wrote:LRRPF52 suggested three loadings- assault rifle, machinegun, and dm/sniper rifle. Another thread I read recently talked about 2 loadings, assault and machinegun, with the first being around 100gr. and the second 140gr. Obviously the sniper and assault loadings would have to have the same COAL due to being loaded in magazines, but what about the machinegun? Could (or should?) you load the heavier 140gr loads longer so as to allow more powder and thus have more velocity and power in a belt fed machinegun which does not have to worry about mag length? Or should they all fit in a magazine?

stanc Wrote:It depends upon whether you wish to discuss what could be done in theory, or what the military is likely to opt for in practice. Historically, a single loading has been used for mag-fed rifles and belt-fed machine guns. IMO, that is unlikely to change, so proposing different loads for the two types of weapons is destined to fail.

coastguardchas Wrote:Stanc: how many different loads for 5.56 do we have now?

Tony Williams Wrote:For the last couple of decades of its existence, the British .303 came in two ball loadings: the Mk VII for mag-fed weapons, and the Mk VIII (a higher pressure loading with different propellant and a boat-tailed bullet) for the belt-fed Vickers.

bwaites Wrote:Don't tell the bullets, or my AR15, but I shoot all the way out to 130 grain bullets just fine out of my AR15 rifles, without having to go over mag length.

Guardsman26 Wrote:First post here. Hello everyone. Ex-UK Army infantry platoon leader point-of-view:
...The 6.5 mm Grendel is undoubtedly the best intermediate calibre cartridge available today. Having seen comparisons of its long-range performance versus improved 5.56 mm and 7.62 mm rounds, I am convinced that it has merit. Where the Grendel comes unstuck is through the requirement to fit within the action length of 5.56 mm weapons...