.264 USA (spin-off from FBI Selection Process thread)

[TiroFijo]

Why would anyone want to introduce yet another cartridge, one that is too long for the 5.56 actions, yet way shorter than 308? There is so much ballistic overlap with current cartridges already.

Adoption of a new round like the .264 USA, or something more or less like that ballistically (the ideal ballistics are not settled, it is a matter of opinion) would only make sense together with lighter cases and perhaps a new generation of guns to fire it.

Combine all these caliber/ballistic decisions , with case material/design/testing decisions, with the new carbine/rifle/MG design decisions... and it is a quagmire. Remember that the USA .mil is not very good at taking any good, fast decisions, and there are many vendors that will want a piece of the pie, even fight a legal battle if needs be. If the MHS competition is any indication, we are in for a looong wait.

[spinmove_]

Why would anyone want to introduce yet another cartridge, one that is too long for the 5.56 actions, yet way shorter than 308? There is so much ballistic overlap with current cartridges already.

Adoption of a new round like the .264 USA, or something more or less like that ballistically (the ideal ballistics are not settled, it is a matter of opinion) would only make sense together with lighter cases and perhaps a new generation of guns to fire it.

Combine all these caliber/ballistic decisions , with case material/design/testing decisions, with the new carbine/rifle/MG design decisions... and it is a quagmire. Remember that the USA .mil is not very good at taking any good, fast decisions, and there are many vendors that will want a piece of the pie, even fight a legal battle if needs be. If the MHS competition is any indication, we are in for a looong wait.

Unlike ballistic overlap in pistol calibers, the rifle caliber overlap would actually make some sense. You can take a cartridge that, while larger than 5.56, is smaller and lighter recoiling than 7.62x51, and would have similar terminal ballistics to 7.62x51. 6.5mm bullets have a nice history of doing their job and doing it well and being flat shooting and lighter recoiling to boot. The case design is lending itself to be both lighter and cheaper to produce while also being size efficient.

I'm not sure if you would really have to come up with a totally different and new rifle design either. Bullpup designs strike me as over complicated and somewhat finicky reliability wise. Why not base it on an AR-15 layout, but make it a piston instead of DI and give it a better recoil system? That would at least help mitigate some of the added recoil over 5.56 as well as help keep the chamber/upper receiver cleaner.

[Eyesquared]

Unlike ballistic overlap in pistol calibers, the rifle caliber overlap would actually make some sense. You can take a cartridge that, while larger than 5.56, is smaller and lighter recoiling than 7.62x51, and would have similar terminal ballistics to 7.62x51. 6.5mm bullets have a nice history of doing their job and doing it well and being flat shooting and lighter recoiling to boot. The case design is lending itself to be both lighter and cheaper to produce while also being size efficient.

I'm not sure if you would really have to come up with a totally different and new rifle design either. Bullpup designs strike me as over complicated and somewhat finicky reliability wise. Why not base it on an AR-15 layout, but make it a piston instead of DI and give it a better recoil system? That would at least help mitigate some of the added recoil over 5.56 as well as help keep the chamber/upper receiver cleaner.

SCAR 17 .264 USA conversion?

[spinmove_]

SCAR 17 .264 USA conversion?

I was actually thinking of more of an MCX .264USA conversion. More compact, takes AR triggers, more of an AR evolution in design overall.

[TiroFijo]

Unlike ballistic overlap in pistol calibers, the rifle caliber overlap would actually make some sense. You can take a cartridge that, while larger than 5.56, is smaller and lighter recoiling than 7.62x51, and would have similar terminal ballistics to 7.62x51. 6.5mm bullets have a nice history of doing their job and doing it well and being flat shooting and lighter recoiling to boot. The case design is lending itself to be both lighter and cheaper to produce while also being size efficient.

I'm not sure if you would really have to come up with a totally different and new rifle design either. Bullpup designs strike me as over complicated and somewhat finicky reliability wise. Why not base it on an AR-15 layout, but make it a piston instead of DI and give it a better recoil system? That would at least help mitigate some of the added recoil over 5.56 as well as help keep the chamber/upper receiver cleaner.

There is no action lenght in between 5.56-308, so I doubt somebody will build one just for a completely new cartridge that does nothing new or needed for 99% of shooters. Just get a 260 Rem/6.5x47/6.5 Creedmore in a 308 lenght action, more power and better long range performance than the .264 USA, and LE/civilians don't need to carry 300 rounds, or worry about compatibility with MG or extra weight of the gun. Or get a 6.5 grendel/6.8 SPC/5.56/300BLK/whatever if size/weight is critical and no LR performance is needed.

The .mil will need a new family of guns if the adopted new round has a case telescoped ammo, if a more conventional polymer case is adopted (unsuccessful technology in this caliber up to this time), then any resized existing gun will do.

IMO, people spend waaay too much time worrying about caliber and gun (rifle or pistol) when there are so many that do the job just fine.

[spinmove_]

There is no action lenght in between 5.56-308, so I doubt somebody will build one just for a completely new cartridge that does nothing new or needed for 99% of shooters. Just get a 260 Rem/6.5x47/6.5 Creedmore in a 308 lenght action, more power and better long range performance than the .264 USA, and LE/civilians don't need to carry 300 rounds, or worry about compatibility with MG or extra weight of the gun. Or get a 6.5 grendel/6.8 SPC/5.56/300BLK/whatever if size/weight is critical and no LR performance is needed.

The .mil will need a new family of guns if the adopted new round has a case telescoped ammo, if a more conventional polymer case is adopted (unsuccessful technology in this caliber up to this time), then any resized existing gun will do.

IMO, people spend waaay too much time worrying about caliber and gun (rifle or pistol) when there are so many that do the job just fine.

Honestly I'm not worried about anything. There are obvious established solutions that are in no danger of going away any time soon. I just find this particular cartridge interesting as I just found out about it and I'm interested to see all what it can do. It looks like it can do some pretty promising and interesting things.

Personally I'm not a long range shooter...yet, so I don't really have a need to go .260REM or 6.5Creedmoor. You're right, I don't run around with 300 rounds on my person as a civilian, so I don't have to necessarily worry about that either on a regular basis. My biggest interest in this caliber is the concept that it could potentially fill different roles and you could logistically source just one caliber for it. Now is that going to happen tomorrow? No way. But it's gotta start somewhere and I'm not the only one who thinks the concept is cool. It not only makes sense for "Joe Average" citizen, but it also makes sense for Big Army as well, even more so in their case. So while they might not be able to pounce on it in the next 5-10 years, they might after that. In the meantime I'll be happy with my 5.56 rifles and whatever other rifles I happen upon in their various different flavors.

[DocGKR]

Ever wonder why there is suddenly so much match grade .260 Rem available now?

[HCM]

.260 Remington and 6.5 Creedmoore seem very similar.

Locally, selection and availability of 6.5 Creedmoore is better.

Is there any advantage to one over the other in an AR-10 platform ?

[BobM]

Didn't the Army look into a new cartridge ( a .276 cal if I recall) between WWI and WWII? I think the reason it was shelved was due to the massive stocks of 30/06 ammo on hand.

[Hambo]

Didn't the Army look into a new cartridge ( a .276 cal if I recall) between WWI and WWII? I think the reason it was shelved was due to the massive stocks of 30/06 ammo on hand.

Yes, and the Brits tested a .280. The history of cartridge development is that the "best" round often isn't the most successful. Ten to fifteen years ago there were people saying that 6.8SPC was going to replace 5.56mm. Now we have other 6-7mm flavors of the month/year/decade. It's going to be a long time and a lot of money before the big .mil opens cans of something other than 5.56mm/7.62mm.