Q I went rifle shooting with a friend recently. His rifle, in 30-06 calibre, had a device called a ‘muzzle brake’ fitted to the threaded muzzle. He said this significantly reduced recoil, he thought by almost 50 per cent, and made his rifle (which was quite light) much more comfortable to shoot, like shooting a much smaller calibre. I have seen adverts for muzzle brakes for shotguns and wondered if they would make a similar difference, like making a 12-gauge feel like a 20. Is that possible?
Patrick Cunningham, Essex
A In theory, yes; a muzzle brake fitted to a shotgun will indeed work in a similar way to the one your friend has on his rifle. However, the degree of recoil reduction will not be so marked. The reason for this is largely due to the hugely different gas pressures that large calibre rifle ammunition produces compared with a typical shotgun. Rifle ammunition uses much more progressive burning propellant powders to accelerate the projectile (bullet) up to two or three times faster than shot emerges from a shotgun, so the pressure and volume of gases emerging from the rifle’s muzzle are much greater than in a shotgun, where the bulk of the powder burn is completed within the first 12 inches of the barrel.
Today ammunition pressures are measured with piezzo-electric sensors and the unit used is the bar; however, the older crusher system with Lead Units of Pressure (LUP, as used by American companies) provides readily recognisable figures for the purpose of this basic comparison. A typical 30-06 cartridge will produce a breech pressure of around 55,000 pounds LUP compared with 8,500 to 10,000 for 12-gauge shotgun ammunition. So there is much less gas left for the muzzle brake to use in countering recoil forces, which, combined with the shotgun’s typically longer barrels means the braking effect of the gases, though potentially still useful especially with heavier loads, is unlikely to match that of a high power rifle. Richard Atkins
