ASK THE GUN EDITOR
Letters containing questions for answering by Nick Harvey must be accompanied by a stamped self-addressed envelope. Mail your letters to: The Technical Editor, 3 Reef Street, Hill End, NSW 2850.
Stability Via Twist
Q I am a fitter-machinist by trade and a novice reloader. I have a couple of questions for you: What happens to a the stability of a 55gn projectile if fired in a rifle with a 1:8" twist? If it remains stable, why buy a rifle with a 1:12” twist that will only stabilise bullets weighing up to 55gn? If I buy a rifle with a 1:8” twist I can shoot bullets from 53 to 80gn which will all be stabilised. Will I improve the measurement of the jump with a fireformed case compared to the one Hornady supplies with their C.O.L gauge? If I could get the Hornady tap I would do it myself, I can relate to a lot of the articles you write.
– Brian Cavanaugh
If a 55gn bullet is fired in a fast 1:8" twist it will be overemphasized, but this doesn’t mean it won’t give good accuracy. A lot depends upon how long the bullet is, how fast it is going when it leaves the muzzle and its construction. In a large case .224 cartridge like the .220 Swift, if the bullet has a thin jacket and soft lead core, the core is likely to melt after leaving the muzzle and will fail to reach
