The.220 Swift is a great, classic Varmint Cartridge

Paul Box, Ballistic Technician at Sierra Bullets, explains the history of the.220 Swift Cartridge.Winchester introduced this cartridge in 1935 for their model 54 rifle. The model 70 was introduced with this cartridge a year later. Some reloaders may not know that the prototype for Swift was developed by Grosvenor Wotkyns in 1934-35, by necking down a 250 Savage case. However, Winchester ultimately chose the 6mm Lee Navy as the foundation of this cartridge. This cartridge was ahead of its time, and as a result it received a great deal of bad press. We’ve read horror stories over the years. Many of the stories were simply re-written versions of previous articles, even if the wording was slightly different. How bad was the Swift then? Let’s look at it in more detail. Some early Swifts were made with soft barrel steel, and some rarer ones had barrels with a.223 bore size. This was due to the fact that some barrels from the.22 Hornets before the end of World War II had a.223 bore size. Rumors were spread that the Swift reached its maximum pressure too quickly. I’ll bet that they did, with a turkey extra-full choke barrel. The Swift’s true potential was also limited by the limited burn rates of powders at that time. It was like building a drag racing car when only kerosene could be found. One of the reasons for the black eye to last so long was because it shot barrels so fast. This can happen if you use the barrel branding iron and do not clean it regularly. Common sense is the best way to go. The accuracy of the Swift will be greatly improved if you keep the barrel as cool and clean it properly every fifteen rounds. What is the truth about this cartridge, then? You’re welcome. I’ve been using the.220 Swift cartridge for over 43 year now. It’s one of the best varmint rounds I’ve owned. It’s not difficult to load, doesn’t have a sudden peak in pressure, and isn’t a barrel burner. Hodgdon Powders reported that a Remington-40-X with 3,000 full power rounds averaged.344″ in five 5-shot groups. My findings were the same. It’s not as bad on barrels as has been reported. I’ve read that a slight down load will improve barrel life. It’s true, but you want your thoroughbred to run. Barrels have threads on the end. Rebarrel the Swift barrel if you’ve had enough fun shooting it. Bottom line, enjoy the.220 Swift as it was intended to be. In the last 20 years, the Swift’s popularity has declined and there are now few factory rifles available in this caliber. There is no explanation for this, and I am confident that the Swift will continue to have a loyal and strong following.