The 243 WSSM was introduced in 2003 by Winchester and Browning. The 243 WSSM was phased out of rifle production by Browning with the launch of the X-Bolt rifle, which replaced the A-Bolt that the 243 WSSM was chambered in. AR-15 rifles were made for a few years after this before they were all phased out.
I have often heard the question, "What's so special about a 243 WSSM compared to the 243 Win?" The simple answer is that the 243 Win. is an excellent caliber and so is the 243 WSSM. They each offer a little different flavor to our hunting and shooting experiences. Here are some of the pros and cons and why I like the 243 WSSM.
243 WSSM Positives
- The 243 WSSM can fit into a shorter action rifle with a shorter bolt, magazine and receiver. This means you get a lighter, smaller rifle that produces a shorter, faster bolt throw. It also means you get a stiffer action that can improve accuracy.
- The 243 WSSM shoots bullets a little faster. Roughly 100-200 feet per second, with just a slightly larger case capacity of 53.0 Gr of water compared to 52.8 Gr in the 243 Win. according to Chuck Hawks.
In theory shorter fatter cases have the characteristics to burn the powder more evenly and consistently, resulting in improved accuracy. - The cartridge is short enough to work in the AR-15 platform. Where the 243 Win. requires the longer action AR-10, which is heavier and more expensive.
243 WSSM Negatives
- Loaded ammunition is expensive.
- Loaded ammunition can be hard to find. (Winchester, Hornady, HSM and Choice Ammo)
- Brass can be hard to find (the best place to find WSSM brass is Hill Billy Brass)
- Some people have reported difficulty with shells feeding. This makes perfect sense, the case is really short and really fat, requiring a little more finesse to make the transition from magazine to chamber than a longer traditional shell. My A-Bolt's magazines required a slight adjustment to get shells to feed smoothly. (see article 243 WSSM A-Bolt Feeding Issues - Solved)
- Because the shells are fatter, you will get one less shell in the magazine in a Browning A-Bolt or Winchester Model 70.
- Rifles are hard to find nowadays (the used market is your only option, other than a custom build)
243 WSSM Myths
- The 243 WSSM burns barrels out really fast.
Wrong! I have not seen nor heard of any evidence that they burn barrels out any faster than any other "magnum" like cartridge. Browning and Winchester also chrome-lined their barrels. Chrome lining can greatly extend barrel life. I personally like how easy it is to clean chrome-lined barrels. I suspect that they were chrome-lined as a precaution before real extensive testing was done on the barrel life. Whatever the case, production rifles from Browning A-Bolts and Winchester Model 70s are chrome-lined. One of these barrels with proper care should last well beyond the amount of rounds most people ever shoot in their lives. - You'd better stock up on brass because they aren't going to make it anymore.
Common sense will tell you that there are far too many rifles out there for Winchester to stop making brass. And more rifles are continuing to hit the market with the AR-15 rifles that continue to get more popular in the 243 WSSM offerings. Now, common sense will also tell you that Winchester would only make runs of brass to meet the demand. If demand goes up or down, they would obviously adjust accordingly.
Where can I find WSSM brass?
- We have a supplier of WSSM brass! Bill at Hill Billy Brass is forming WSSM brass from WSM brass. Thank you Bill!
Where can I find 243 WSSM ammo?
- MidwayUSA stocks Hornady, HSM, Winchester and Choice 243 WSSM Ammo
Where can I find a 243 WSSM rifle?
AR-15 rifles were the last of the production rifles to be made and they are no longer in production. The used market or having a custom rifle built are your only options in 2026. Here are the rifles I am aware of that you can look for on the used market.
- Browning A-Bolt - Bolt Action Rifle
- Winchester Model 70 - Bolt Action Rifle
- Olympic Arms AR-15 WSSM Rifles
- Accuracy Systems builds various 243WSSM AR-15 rifles and barrel options.
- Dtech Custom AR-15 243 WSSM Upper Receivers
If you like to tinker at the reloading bench with different bullets, powder and the like, the 243 WSSM might be for you. If you are looking for a rifle that's a little faster shooting and lighter to carry, the 243 WSSM might be for you. If you spend a good deal of time hunting and hiking in rugged, tough country, a little lighter rifle might be for you. Now on the other hand, if you like to grab a box of ammo at Walmart as you're heading out of town to your hunting lease the 243 WSSM isn't for you.
I think the 243 Win. is an excellent cartridge and I have always been fond of it. My father's deer rifle is a Sako Forester chambered in 243 Win. In my youth I watched my father shoot mule deer with it and I'd hear the stories from the guys in his hunting party talking about how they would all miss at long range with their 30-06's and my dad with his little 243 would get them every time. Boy, how I thought that rifle was the best rifle in the world. Some day I hope to own my father's rifle but we'll have to see as I have two brothers who have their eyes on it as well.
I don't think you can go wrong with either cartridge as long as you understand what might be an advantage and what might be a disadvantage for your individual hunting and shooting style. The 243 Win. is an outstanding caliber and for the gearhead that I am the 243 WSSM is just as outstanding. Many a deer has fallen to a .243/6mm diameter bullet throughout the years, and the 243 WSSM cartridge pushes this 6mm bullet quite well.
The 243 WSSM has also been deadly on elk. In 2009 my son made a 205 yard one shot kill on his first elk bull elk with a 243 WSSM and a 272 yard one shot kill cow elk with a 243 WSSM, and again in 2010 Dallen took a cow elk with a single shot at 110 yards with a 243 WSSM.
To view my favorite handloads for the 243 WSSM, check out my 243 WSSM Handloads and Ballistics page.
In 2019 I found a new favorite 6mm cartridge, especially for long range shooting. That cartridge is the 6mm Creedmoor and I now own two 6mm Creedmoor X-Bolt rifles.