Remington has a long and successful history of bringing popular wildcat cartridges to "standard cartridge" status by locking in dimensions and pressure and velocity assignments, standardizing names, and submitting to SAAMI. One of these is a premier varmint cartridge: the .22-250 Remington.
As the name implies, this is the .250 Savage case necked down to hold .22-caliber bullets. In its commercial incarnation, the .22-250 shares almost every dimension with its wildcat parent except for an almost imperceptible 1.5-degree difference in shoulder angle. It is an elegantly simple conversion.
The history of this cartridge in its wildcat days is cluttered with conflicting information. Many experimenters in those days were working with the .250 Savage case. Some of the best information I found is almost contemporaneous to the cartridge. Phillip B. Sharpe's classic Complete Guide to Handloading was first printed in 1937, and Sharpe later added supplemental sections. J.E. Gebby developed the version he called the "22 Varminter." Other references suggest Gebby's final version appeared close to Sharpe's first printing.
Sharpe is very complimentary of Gebby's diligent attention to detail in the development of the cartridge. He says Gebby retained the .250 Savage's 26 degrees, 30 minutes shoulder angle, considered fairly steep in that era. However, what drove me to drag out my well-worn copy of Sharpe's treatise was velocity.
I wanted to know in the days when practically no one owned a chronograph how did Gebby's wildcat 22 Varminter compare to today's .22-250 Rem. Sharpe had access to chronograph equipment and published some velocities. He was a careful researcher, listing both measured and estimated velocities, the latter clearly denoted with the letter "E" after the value to avoid confusion.
Most of us who know the .22-250 as a commercial cartridge benchmark it with a 55-grain bullet exiting the muzzle between 3,600 and 3,700 fps. Among the actual 22 Varminter velocities Sharpe reported are loads reaching that speed range. The old wildcat was making modern velocities with pre-World War II propellants. Today, only the newest reloading fuels can exceed that with a 55-grain bullet in the commercial .22-250. Hodgdon's excellent online reloading data show only IMR 4007SSC, IMR 4166, IMR 8208XBR, and Hodgdon CFE 223 breaking 3,750 fps with a 55-grain bullet in a 24-inch test barrel. To me that says Gebby got it right long ago.
Gebby went to the expense of obtaining U.S. copyright protection for the name "22 Varminter." Others used different names to avoid intellectual property entanglements, the most common being .22-250. It was one of the most popular wildcats ever, which was surprising considering that Winchester's factory-loaded .220 Swift had existed since 1935. In 1965 Remington standardized the cartridge with the .22-250 designator, opting for a 28-degree shoulder angle. The velocity standard with a 55-grain bullet is 3,650 fps, and the maximum average pressure (MAP) is 65,000 psi, 3,000 psi higher than the .220 Swift.
Once we include the speedy .220 Swift in this discussion, it is hard to stop comparing. Current SAAMI velocity recommendations have both cartridges pushing 55-grain and 60-grain bullets at the same speed. For lighter bullets the .220 Swift has roughly a one percent advantage, which is too little to keep even campfire discussions lively for much longer than one beer.
The .22-250 Rem. achieves top velocities with most of the mid-rate rifle propellants. However, you don't lose too much velocity if you load with something even as slow as IMR 4350. It will still push a 55-grain bullet to 3,400 fps. In most rifles, case life seems decent, too. I strongly recommend that reloaders check case lengths after every two firings. When you have 65,000-psi gases charging through a .22-caliber hole, case necks can lengthen. Trim them as needed.
When seating primers in cases that have experienced multiple firings, pay attention to your "educated" hand. Feel for loose primer pockets, evidenced by primers that seem too easy to seat. Discard any with loose pockets to avoid boltface damage. One acquaintance for whom buying new cases could tax the household budget always loaded his .22-250 with slower-burning fuels. That kept pressures down a bit for increased case life, and he said the prairie dogs never complained about the slight velocity loss.
Let's talk about twist rate. The SAAMI standard .22-250 Rem. twist is 1:14. This is perfect for traditional bullets up to 55 grains. Today, we see bullets getting longer than traditional bullets of the same weight. Tipped bullets, boattail bullets, and all-copper bullets can all be longer than the flatbase softpoint bullets that dominated the varmint market for years. While wrapping up the Speer Reloading Manual #14, I had the lab do .22-250 stability tests with a prototype 62-grain SPBT that was intended for the .223 Remington. At 100 yards they shot under an inch, but they printed nearly 3.5 inches at 200 yards. That non-linear group size increase indicates the bullets were under-stabilized in a 1:14 twist barrel. If the bullets were properly stabilized, that 200-yard group would have been closer to 2 inches.
I think the .22-250 can benefit from bullets heavier than 55 grains, especially on windy days, but the 1:14 twist can make that tricky. Short-nosed bullets like Sierra's 63-grain semipointed SP work well; I shot many through an old custom rifle in my youth. However, some people prefer a more streamlined design. I think rifle manufacturers could better mate the .22-250 to modern bullet designs by offering a 1:12 rate. Could it be faster than 1:12? Maybe, but I worry that too fast a twist could disassemble conventional 45- to 50-grain varmint bullets as they leave the muzzle.
Although I did not check every rifle manufacturer's rifling specs, there is one riflemaker that, in my opinion, modernized .22-250 twist rates long ago: Savage. It has shown a 1:12 rate for .22-250 rifles at least as far back as my joining Speer in 1987. That one piques my interest, and the company may get some of my money.