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Thus the optimum rate of twist for this bullet should be approximately 12 inches per turn. The typical twist of .30-06 caliber rifle barrels is 10 inches per turn, accommodating heavier bullets than in this example. A different twist rate often helps explain why some bullets work better in certain rifles when fired under similar conditions.
Civilian AR-15 rifles are commonly found with 1 in 12 inches (30 cm) or 54.8 calibers for older rifles and 1 in 9 inches (23 cm) or 41.1 calibers for most newer rifles, although some are made with 1 in 7 inches (18 cm) or 32 calibers twist rates, the same as used for the M16 rifle. Rifles, which generally fire longer, smaller diameter bullets ...
A 254 mm (1 in 10 in) twist rate is also commonly applied. [ 11 ] According to the official C.I.P. ( Commission internationale permanente pour l'épreuve des armes à feu portatives ) rulings, the .308 Winchester can handle up to 415.00 MPa (60,191 psi) P max piezo pressure.
For a typical .338 Lapua Magnum high-end factory military sniper rifle like the Sako TRG-42 with a 690 mm (27.2 in) long 305 mm (1 in 12 inch) rifling twist rate barrel at sea level, 1,500 m (1,640 yd) is considered to be the maximum shooting distance for man-sized targets. When using standard Lapua military 16.2 g (250 gr) loads it has a ...
The common rifling twist rate for this cartridge is 220 mm (1 in 8.66 in), 4 grooves, ... Complying barrels have usually been marked with "6,5 × 55 SKAN".
The 7×64mm offers very good penetrating ability due to a fast twist rate that enables it to fire long, heavy bullets with a high sectional density. The 7×64mm's rimmed sister cartridge, the 7×65mmR, is also very popular in Central Europe for the same reasons as the 7×64mm.
Due to the large case capacity in relation to the 6.5 mm (.264 inch) calibre bore size the 6.5×63mm Messner Magnum is very harsh on barrels. It typically wears out a rifle barrel in 500 to 1000 rounds. A lot of thorough barrel cleaning (after every 5 shots) and carefully avoiding long strings of shots help to minimize barrel wear.
Common rifling twist rates also often have to be tightened to stabilize very long projectiles. Such commercially nonexistent cartridges are termed "wildcats". The use of a wildcat-based (ultra) long-range cartridge demands the use of a custom or customized rifle with an appropriately cut chamber and a fast-twist bore.