Speaking of TFB, he confirms that the CTSAS program (what used to be LSAT) is indeed looking into a 6.5mm round now. Though, of course, they're doing it in precisely the wrong way. They have essentially recapitulated the .260 Remington in plastic cased telescoped form, which is more of a replacement for the 7.62x51mm round but absolutely not the 5.56x45mm round. Look at the size and weight, fer chrissakes! It's the same as the 7.62mmCT, both projectile weight and total cartridge weight- only the recoil is a bit better. Somebody is having a serious error in concept, here, unless there is some requirement that isn't being mentioned. Admittedly, though, they say that they're using the same CT case for 6.5mm as the 7.62mm strictly for convenience during development (using same weapon just by swapping barrels) and it will probably get lighter. Still, it's too powerful despite whatever their 4-dimensional analysis says, so I agree with Nathaniel, there.
Since the trend nowadays is for other-than-lead projectiles (see EPR) that are more structurally rigid than the lead ones, and since they get to start from scratch anyway because they are designing a totally new cartridge, what they should be doing (IMNSHO) is taking the opportunity to design a long, skinny, slightly heavier 5.56mm or 6mm projectile with the same insanely good ballistic coefficients as the 6.5mm ones. (Because the only reason that the 6.5mm rounds have those nice BCs is essentially historical.) Then they'd have their lightweight longer-ranged rifle round, as opposed to what is essentially a marginally-improved AR10 in .260 Remington.
Which, nothing against .260 Remington- I own one- but it sure shouldn't be a service rifle round.
Since the trend nowadays is for other-than-lead projectiles (see EPR) that are more structurally rigid than the lead ones, and since they get to start from scratch anyway because they are designing a totally new cartridge, what they should be doing (IMNSHO) is taking the opportunity to design a long, skinny, slightly heavier 5.56mm or 6mm projectile with the same insanely good ballistic coefficients as the 6.5mm ones. (Because the only reason that the 6.5mm rounds have those nice BCs is essentially historical.) Then they'd have their lightweight longer-ranged rifle round, as opposed to what is essentially a marginally-improved AR10 in .260 Remington.
Which, nothing against .260 Remington- I own one- but it sure shouldn't be a service rifle round.
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