21 SHARP – New Rimfire Cartridge from Winchester
SAAMI (Sporting Arms and Ammunition Manufacturers’ Institute) have published cartridge and chamber drawings of a new rimfire cartridge called 21 Sharp which was developed and submitted for SAAMI acceptance by Olin Winchester. While this new cartridge uses a non-heeled projectile, it has a lot of similarities with the 22 Long Rifle. Let’s take a closer look at the design of the new 21 Sharp rimfire cartridge.
New SAAMI Approved Cartridges @ TFB:
The new 21 Sharp cartridge not only operates at the same Maximum Average Pressure of 24,000 psi and has the same overall length (1″) as the 22 LR, but it also apparently uses the 22 Long Rifle cartridge case – case dimensions of the two cartridges are literally identical. So looks like Winchester engineers created this cartridge by simply designing a non-heeled bullet that fits the 22 LR case which resulted in a non-standard bullet diameter of .2105″ (5.347mm).
Per SAAMI specs, the 21 Sharp launches a 25-grain projectile at a muzzle velocity of 1,725 feet per second. The length of the SAAMI test barrel is 24″ and the twist rate is 1:12″. The bullet shape shown in the SAAMI drawing is for illustrative purposes only. With the overall length, rim dimensions and MAP being identical to 22 LR, it should be easy to convert 22 LR firearms to 21 Sharp by simply swapping the barrels. The actual release of the new cartridge and firearms chambered in it will hopefully follow the SAAMI standardization. It’d be interesting to see what types of bullets 21 Sharp will be loaded with and which markets it is primarily designed for.
Pictures by SAAMI, www.saami.org
Managing Editor Being a lifelong firearms enthusiast, Hrachya always enjoys studying the history and design of guns and ammunition. Should you need to contact him, feel free to shoot him a message at Hrachya@TheFirearmBlog.com
More by Hrachya H
Comments
Join the conversation
I was hoping for a .20 or .22 or .23 cal. version of the .17 WSM.
We do not know yet how much the smaller bullet will let gas pass when you shoot it in a regular 22 long rifle chamber. A match gun may vary a lot from an older gun made 40 years ago. There is a variance with specs of only 0.0065 inch, that is not much. With a softer projectile like the frangible they propose, it might just work OK at normal 22 lr ranges under 50 yards. Time will tell.
I am buying CCI 22 mag locally for $15.00. They need to be much less for me to downgrade to the 21 sharp.