10-21-2020, 09:56 PM
LRRPF52 Wrote:The 0.419" diameter of the 5.56 CT cases is smaller than the 0.504" diameter of the 7.62 CT cases by almost exactly the same amount (0.085") as the difference in bullet diameters (.308 - .224 = 0.084").stanc Wrote:BTW, if you're wanting to go to 6.5mm to decrease cartridge bulk, that would not help significantly.The bulk also comes from the propellant volume required to push a heavy .277 projectile that is heavy in order to meet the BC required to retain enough energy for the terminal requirements at distance.
.277 - .264 = 0.013
Reduce the polymer case diameter by 0.013" and it'll still be at least as fat as the 7.62 NATO round.
The 5.56 LSAT cases are much smaller.
LRRPF52 Wrote:I think a .243" or .257 high BC EPR projectile would be far more ideal than .277 for these reasons. It would lighten the overall system as well since the recoil force is substantially different. You dont need as much chamber pressure to reach the same performance requirements, and have better sectional density for the armor-defeat metric.Even with smaller calibers, we're still looking at fat cartridges, with case diameters of ~0.44" for 6mm CT and ~0.45" for 6.35mm CT.
This would also allow the rifle version to fit a smaller form factor, with 30rd mags, as opposed to these large mags required for the NGSW rifle variant.
30-rd mags for 6mm or 6.35mm would still be quite bulky, almost two inches taller than the 20-rd 6.8 NGSW mags, and only ~0.1" slimmer. With 6.5mm CT, like some here want, the difference in magazine dimensions would be negligible.
LRRPF52 Wrote:Magazines have weight too, so when you cut round count in favor of performance, you increase the magazine count even for a lesser overall combat load, while also making it more difficult to store those magazines on load bearing kit.Yeah, I'd really like to see what they are planning for this. The videos I've seen show NGSW shooters with few or no spare mags.
LRRPF52 Wrote:Another major problem I see is that just as soon as something like this gets finalized and produced, the intended threat simply upgrades their body armor.You're not alone in that observation.
There are advancements in armor technology currently underway that threaten to make small arms even less effective.
