The alternative to lighter bullets or heavier weapons systems is to settle for lower muzzle velocity which produces poorer external ballistics at close ranges with more drop,windage and target movement,but even then,the 6.5mm Creedmoor could never match the combination of high muzzle velocity and high ballistic coefficient (and hence excellent long and short range external ballistics) of the Quarter Inch cartridge proposed here,despite being both bigger and heavier.

The Three Eighths Inch carbine cartridge proposed on this site actually fires relatively light for calibre bullets with a lower ballistic coefficient,because it is designed for use at the shorter ranges found in confined spaces,a high ballistic coefficient is of little importance at short ranges but lower sectional density offers internal ballistic advantages which permit the use of shorter barrels,for the same muzzle velocity,which are desirable in a weapon designed for use in a confined space. It would be possible to fire lighter bullets to get a higher muzzle velocity and a flatter short range trajectory but they would have a lower ballistic coefficient and therefore perform poorly at longer ranges.

The entire weapon system ends up being bigger,heavier and harder recoiling in order to obtain the same external ballistics,and hence hit probability,which is a problem for an already overloaded infantryman. This means it is necessary to impart more energy to the bullet to obtain a given muzzle velocity (which is the dominant external ballistic factor at short ranges),which in turn requires some combination of a larger cartridge (and magazines),longer barrel or higher operating pressures. The biggest problem with 6.5mm cartridges is that they need a higher bullet weight to obtain the same Ballistic Coefficient (B.C.) as a lighter Quarter Inch bullet (and if it is to be a lead free bullet that weight would also consume significant powder volume). They are very well suited to upgrading existing 7.62x51mm weapons which need a barrel change but have plenty of life left in them (sadly the British armed forces seem to have little interest in that idea) but still have significant disadvantages when compared to an all new cartridge in an all new weapon. 260 Remington) and which were amongst hundreds considered. The Quarter Inch cartridge mentioned here was conceived many years before Creedmoor was adopted for military use,in fact before it was even released,but there were similar cartridges available back then such as the 6.5-08 (later 6.5-08 A-Square and.

5.8x42mm vs 5.56x45