Tony Williams Wrote:Some thoughts on the options for a GPC (General Purpose Cartridge) which could replace the 7.62x51 in portable small arms carried by dismounted infantry with substantial reductions in weight and recoil (and could also replace the 5.56mm in the infantry squad, although that would stick around for a long time in non-infantry applications).Looks good. Ought to work.
I start with the assumption that the ideal GPC cannot be accommodated in the AR-15 platform.
The three versions show 6.35mm, 6.5mm and 6.8mm calibres. These were chosen because the ARDEC calibre survey tested cartridges in 6.35mm and 6.8mm (but not 6.5mm) and concluded that these two were both better than 5.56mm, 6mm or 7.62mm.
There is obviously room to extend the OAL to accommodate lead-free bullets.
Comments?
The 0.42" case offers a slight advantage to machine gun belt length (for 100 linked rounds).
The 0.44" case gives a small advantage to rifle magazine ergonomics (front-to-rear dimension).
No significant weight difference between the two case options. Probably no significant difference in muzzle velocities, either.
Major drawback to both is the non-availability of platforms optimized for intermediate-length, intermediate-diameter cartridges, which means it'd be necessary to use the bulkier, heavier weapons developed for 7.62x51 (such as the AR-10, Mk17, etc).