By Pete Petros-Lead Reloading Technician, Sinclair International

For generations reloaders have been trying to find the ultimate long range cartridge. Many wildcat cartridges have come and gone through the years. Many reloaders invented “new” cartridges by necking up or down a parent case, or blowing out the shoulders or body. Some of the more popular and well performing ones became production loads and mainstays of competitive shooters. Cartridges such as the 6.5mm X .284 Norma, .260 Remington, 6.5mm-06 and the many 6mm’s that have been based off the .243 case are only a handful of these. As technology has increased it has introduced more efficient and high energy powders, super sleek bullets with high ballistic co-efficients, and the means to prep components and measure them for consistency.

The past two years in long range, shooting a cartridge that has been proving itself especially in the F-Class Open competition is the .284 Winchester, the parent case of the popular 6.5mm X .284 Norma. This old original is now making a comeback. Originally designed by Winchester in the early ‘60’s for the Short Action Model 88 and 100 rifles, it was meant to pack the same punch as a .280 Remington (7mm Express), but in a short action configuration. Winchester developed the shorter case with a rebated rim the same size as the .308 Winchester and gave it a larger case head close to the same size as some belted magnums. The original cartridge did prove itself as an efficient hunting round, but immediately it gained the interests of reloaders looking for new wildcats. It has been modified down to .22 caliber all the way up to .35 caliber and beyond through the years. It was found that necking down to the parent case to smaller calibers would create super high velocities with decent accuracy.

The 6.5mm X .284 Norma developed from the .284 Winchester parent case became the most popular cartridge in the .284 Family. The difference between the “Winchester” and the “Norma” .284 is that the Norma case is .005” thicker in the web area of the case head. The same dies can be used for both varieties.

With the increase and availability of more 6.5mm bullets with higher performance designs, the 6.5mm X .284 Norma became a force to be reckoned with in the long range circles. This cartridge has proved that it is flat shooting and super accurate, and has won many fans. It has become so popular that major manufacturers have chambered rifles in 6.5mm X .284 and factory loaded ammunition is also available. However as accurate as it may be this cartridge has one large disadvantage. It is a true barrel burner and if a shooter is lucky they will get between 1500-2000 rounds before re-barreling. This is where my experience with its parent cartridge began……Continued next Week!

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