Locksley
Well-Known Member
.243 Winchester
The .243 Winchester is a popular sporting rifle cartridge. Initially designed as a varmint round, it is now more frequently used on medium to large game such as whitetail deer, mule deer, pronghorn, wild hogs, and even black bear and caribou. However, due to the smaller caliber bullet used, its suitability for large animals is dependent on skill level and the hunter's ability to make a clean and accurate shot. The .243 is based on a necked down .308 cartridge case and is known for its accuracy, flat trajectory, and relatively mild recoil.
History
This cartridge was first introduced in 1955 for Winchester's Model 70 bolt-action and Model 88 lever-action sporting rifles and quickly gained popularity among sportsmen worldwide.[1] Just about every major manufacturer offers rifles chambered in .243.
Since the enactment of the 1963 Deer Act in the United Kingdom, which stipulated a minimum bullet diameter of .240 in., together with minimum levels of muzzle velocity and bullet energy, the .243 is now perceived as the entry-level caliber for legal deer-stalking. Consequently, it is now the most widely used deer round in the United Kingdom.[citation needed] Firearms that would normally be chambered in .308 Winchester/7.62x51mm NATO are sometimes available in .243 in. countries � such as France and Spain � whose regulations restrict or forbid private ownership of so-called military calibers.
In a non-sporting, non-civilian context, bolt-action rifles chambered for the .243 were utilized by the Los Angeles Police Department's Special Weapons And Tactics (SWAT) unit during its early years.[citation needed]
P. O. Ackley created an improved version of this cartridge called the .243 Winchester Improved (Ackley).[2] Like other improved cartridges, this created a steeper shoulder and blew the sides out, plus slightly lengthens the case, giving about 10% more powder capacity, and some small improvement in velocity. Both versions of the .243 cartridge are good for hunting deer.
Performance
The .243 produces a velocity of 2,960 feet (902.21 m) per second with a 100 grain (6.6 gram) projectile from a 24-inch (610 mm) barrel. Commercially loaded .243 ammunition is available with bullet weight ranging from 55 grains (3.6 g) up to 105 grains (6.8 g), typical bullets being in the 75�90 grain (5-6 g) range.
The .243 has gained substantial worldwide popularity, and commercially loaded ammunition is easy to find on every continent. Along with the .270 Winchester, the .308 Winchester, .223 Remington, and .30-'06, it is among the most popular and widely available of all centrefire cartridges
http://en.wikipedia.org/wiki/.243_Winchester
.243 Win + .243 AI Cartridge Guide
High-Velocity 6mm for Long-Range, Varminting, and Tactical Use
243 Win--Multi-Purpose Precision
If you could have just one rifle to slay varmints, hunt white-tails, shoot paper at long range, and duel in tactical matches, it would be hard to beat the .243 Winchester. This versatile "little brother" of the .308 Winchester is a true triple-threat as a match cartridge, varmint cartridge, and game cartridge. With 115gr DTAC bullets, a .243 rivals a 6.5-284 ballistically out to 1000 yards. Shooting 80-100 grain hunting bullets, a .243 will anchor a buck with authority. Driving the light 55-75 grain pills, the .243 provides the flat trajectory and high impact energy varminters love. As a tactical round, the .243 is one of the best, offering excellent ballistics, moderate recoil, and stone-reliable feeding from a detachable magazine.
The .243 Win excels with a wide variety of powders, and excellent factory-loaded hunting ammunition is available. Off-the-shelf .243 rifles from Howa, Remington, Savage, and Tikka perform admirably with little or no modification. The "improved" version of the cartridge, the .243 Ackley, can do everything its parent can do, with more velocity, and greater brass stability thanks to its 40� shoulder. Among the Ackley variants, the .243 AI is rightly one of the most popular. It is easy to fire-form, and commercial dies are readily available. Barrel life is the downside of both the .243 AI and standard .243. These chamberings pump a lot of powder through a small bore. The result, typically, is rather short barrel life, sometimes less than 1500 rounds. A few folks have been experimenting with the use of very slow, cooler-burning powders. There is some evidence that the use of super-slow powders, combined with modified cleaning regimens, can result in significantly enhanced barrel life.
Brass--An Abundance of Good Choices
.243 Win shooters are fortunate as Lapua, Norma, and Winchester all make good brass for this caliber. We've shot all three brands. The Lapua and Norma both yielded excellent accuracy, and both brands were very consistent weight-wise. The primer pockets did stay tight a bit longer with the Lapua, and the neck tension stayed more constant after repeated firings. Since Lapua .243 brass is usually less expensive than Norma, Lapua is our first choice. But if you find some Norma .243 cases at a good price, don't hesitate to buy them. You may have to adjust your load a bit as the Norma we tried had slightly higher H20 capacity than the Lapua brass.
Domestic (Remington and Winchester) brass is significantly less expensive than Lapua or Norma. If you sort the cases by weight and clean up the primer pockets and flash holes, Win brass can shoot very well indeed. Winchester would be our first choice if you need large quantities of brass, or are shooting tactical matches where it's common to loose brass in the weeds. One Midway user observed, however: "[I prefer] Remington brass over Winchester, due to the different internal volume of the brass. Since the internal volume of Remington is smaller I seem to get more consistent results from both the chronograph and down-range performance."
For varminters, the Sierra 70gr Blitz-King and Hornady 75gr V-Max offer a good combination of accuracy, BC, and explosive impact on target. The Berger 80gr Varmint bullet is exceptionally accurate but doesn't impact as explosively on target. For coyotes, the 80gr Nosler Ballistic Tip and Hornady 87gr V-Max both buck the wind pretty well and hit hard. For small to medium-sized deer, Sierra recommends its 85gr HPBT GameKing for soft-tissue shots out to 200 yards. Where deep penetration and better weight retention is required, you need bullets like the Nosler 95gr/100gr Partitions, Remington 100gr Core-Lokt? SP, or the Sierra 100gr SPFB Pro-Hunter. Click Here to download Nosler Partition Video (requires QuickTime).
Hunter and outdoor writer Chuck Hawks notes: "When using the .243 to hunt medium-size big game animals, bullet selection is paramount. Rapid (but controlled) expansion is very important, as the small diameter 6mm bullet has little shocking power if it does not expand and expend its energy inside of the animal. Two bullets in the 90-100 grain weight range that have earned a good reputation on medium size big game animals are the Remington Core-Lokt and Nosler Partition."
.243 Win For Tactical Comps We asked GA Precision's George Gardner why he chose .243 Winchester for his Tactical Comp Gun. He replied, "Why would I run anything else? Think about it. I'm sending a .585 BC 115 at 3150 fps--that'll shoot inside the 6XC and .260 Rem with ease. I'm pretty sure I have found the Holy Grail of Comp Rifles. There are no brass issues like you can get forming .260 brass. I don't have to worry about doughnuts, reaming necks--none of that. And the choice in brass is great too--run Lapua if you want max reloads and great accuracy. Run Winchester if you're on a budget, and so you won't cry if you lose some cases in a match. I can get 10-round mags, and feeding is 100% reliable, since the case is identical to a .308 except for the neck. Accuracy-wise, I don't think I'm giving up anything to the .260 Rem or the 6XC." We then asked George if he'd considered using a .243 AI instead: "Yeah, the cases look cool with that 40� shoulder, but I think the standard .243 feeds a little better. And I don't think I really need the extra performance of an improved case. Run the ballistics for my load--115 moly DTAC at 3150 fps. You've got less windage than a 2950 fps 6.5-284, with cheaper brass, cheaper dies, cheaper bullets, and less recoil."
http://www.6mmbr.com/243win.html
.243 Ackley Improved--More Velocity, Less Case Stretch
by Bob Blaine, Sinclair International
Parker Ackley reluctantly developed the .243 Ackley Improved ("AI"). Ackley finally gave in to his customers' requests to develop the .243 AI. He had always felt that the .243 Winchester was already an improved configuration, but he did say that the best thing to be gained by improving the .243 Winchester was to substantially reduce the case-stretching problems. The .243 Winchester parent case has always stretched brass, almost as bad as the Swift. Even though you get more velocity with the improved .243, I've also found that the improved version gives a bit more throat life than the parent case does.
The .243 AI delivers more velocity by virtue of enhanced case capacity--roughly five grains more H20 capacity than a standard .243 Winchester. The .243 AI has a water capacity of approximately 57 to 58 grains, compared to 52-53 grains for the standard .243 Winchester.
Fire-Forming
As always, fire-forming is done by one of two methods. Most of you will fire form the brass with loaded .243 Winchester. Ackley always said to use factory loads, or reload equivalent ammo to have a "snappy" load to form the case out properly. You never want to use a reduced load to form with, since you need the pressure to form properly. If your rifle is chambered properly, you should feel a slight amount of resistance as you close the bolt on a new piece of brass. If you do not get this "feel", you may need to seat the bullets out to .010" to .015" into the lands to make sure that the base of the case stays in solid contact with the bolt face. The fire-forming method I have been using more lately employs medium burn-rate pistol powders and Cream of Wheat. I will start by loading about 10 grains of SR4756 or Unique into the case, and then I fill the case up to the body shoulder junction with Cream of Wheat. I will then take a large pinch of polyester filler, which can be found at any fabric supply store, or sewing department, such as at Wal-Mart. I will then take the pinch of polyester and load it into the case so that it fills up the shoulder area of the case effectively making sure that the filler is held securely over the powder for fire-forming. During the fire-forming, I like to dry brush with a nylon bore brush every 10 to 15 rounds. This removes any loose debris from filler that has accumulated. [Editors Note: Do NOT seat a bullet using this "Cream of Wheat" method. You can cap the case with a bit of wax to keep everything in place. However, Bob finds the wax is not necessary if the polyester filler is placed securely.]
Recommended Loads
I'm often asked, "what gunpowder do you recommend"? I generally recommend medium-slow or slow burn-rate powders for the .243 Ackley. I have found, with my rifle, that H414 is pretty much my first choice for use in the .243 AI. H414 tends to give me great accuracy, with good velocity. Saying this, I have tried many other propellants and have found the following powders to be worth looking at for your needs: AA-2700, H414, H4350, VV N150, VV N550, VV N160, VV N560, RL19, H4831sc, and VV N165, to name a few of the powders that I have tested over the years.
Different Reamers, Different "Improveds"
One thing that you need to watch for is what version of the .243 Improved that you have. This depends, for the most part, on whose reamer you will be using for the chambering of your barrel. It is easy to determine if your .243 Improved is the .243 Ackley Improved, or the .243 Winchester Improved. If you have the .243 Ackley Improved, the shoulder-body section will measure .460" dia. at this point. If you have the .243 Winchester Improved, the shoulder-body section will measure .455" diameter at this point. Both cartridges have the 40-degree shoulder. I have used both versions and found that you can use any data developed for either version interchangeably.
The .243 Ackley Improved is one of the best long range varmint rounds going, and can add some extra punch for your light big game rifle as well. One would be hard pressed to ignore a cartridge as versatile as the .243 Ackley Improved.
Matt's Screamin' Yellow Ackley--The Need for Speed
.243 AI Speed Demon
In a long-range varmint rifle, speed kills. Ultra-high velocities deliver flatter trajectories and more explosive hits. And that's where the .243 Ackley really shines. While we don't advocate "pushing the limits" with factory actions, Matt Bianchini has explored the upper limits of .243 Ackley performance with his Farley-actioned long-range rig, fitted with a 29" Lilja 3-groove, 8-twist barrel. Using a stout load of Reloader 25, Matt's "Screamin' Yellow Ackley" has topped 3340 fps with Clinch River 106s. That is serious speed for heavy 6mm bullets. This shows a well-built .243 AI leaves Dashers and 6XCs in the dust when it comes to pure velocity.
Dies and Reloading Gear
Since the .243 Win is such a popular cartridge, all the major die-makers offer reloading dies. It's hard to go wrong with a Redding Type 'S' Full-length bushing die--item 77114 for the standard .243 Win and item 77420 for .234 AI (40?). This will both resize the case (and bump the shoulder) as necessary, and allow you to adjust neck tension with bushings. Alternatively, you can go with a body die (item 75114), and a separate neck bushing die (item 71114).
If you load primarily one brand of bullets, another slick set-up is to buy a Forster full-length .243 sizing die, and then send it off to Forster to have the neck honed for your desired amount of tension. Forster charges just $10 plus shipping for this service. This elegant one-pass sizing solution produces very straight rounds with low run-out. We also believe that doughnuts (in the neck) form less readily if you full-length size with non-bushing dies as opposed to using bushings. Bushing dies leave a little bit of the neck unsized, and that's where the brass can build up.
For bullet seating, both the Redding Competition Seater (item 55114) and the Forster Ultra-Seater (item U00034) work great for the standard .243 Win case. If you shoot a .243 Ackley, Redding's .243 AI Comp Seater (item 55420) costs quite a bit more than the standard version and Forster doesn't list a .243 AI seater in their catalog. However, you can just run your chambering reamer into the inner sleeve of either die to fit the Improved case.
If you want the "Cadillac" of production seater dies for the .243 Win, order the Wilson Stainless Micrometer seater (item 50-1114S) from Sinclair International. Costing only a few dollars more than a Redding Comp seater, this die is a joy to use, providing very positive control over bullet seating depth. When used with a quality arbor press, the Wilson offers unrivaled "feel" for bullet-seating force. This can help you monitor neck tension, one of the most critical factors in maintaining low ES and SD for long-range accuracy.
http://www.6mmbr.com/243win.html
The .243 Winchester is a popular sporting rifle cartridge. Initially designed as a varmint round, it is now more frequently used on medium to large game such as whitetail deer, mule deer, pronghorn, wild hogs, and even black bear and caribou. However, due to the smaller caliber bullet used, its suitability for large animals is dependent on skill level and the hunter's ability to make a clean and accurate shot. The .243 is based on a necked down .308 cartridge case and is known for its accuracy, flat trajectory, and relatively mild recoil.
History
This cartridge was first introduced in 1955 for Winchester's Model 70 bolt-action and Model 88 lever-action sporting rifles and quickly gained popularity among sportsmen worldwide.[1] Just about every major manufacturer offers rifles chambered in .243.
Since the enactment of the 1963 Deer Act in the United Kingdom, which stipulated a minimum bullet diameter of .240 in., together with minimum levels of muzzle velocity and bullet energy, the .243 is now perceived as the entry-level caliber for legal deer-stalking. Consequently, it is now the most widely used deer round in the United Kingdom.[citation needed] Firearms that would normally be chambered in .308 Winchester/7.62x51mm NATO are sometimes available in .243 in. countries � such as France and Spain � whose regulations restrict or forbid private ownership of so-called military calibers.
In a non-sporting, non-civilian context, bolt-action rifles chambered for the .243 were utilized by the Los Angeles Police Department's Special Weapons And Tactics (SWAT) unit during its early years.[citation needed]
P. O. Ackley created an improved version of this cartridge called the .243 Winchester Improved (Ackley).[2] Like other improved cartridges, this created a steeper shoulder and blew the sides out, plus slightly lengthens the case, giving about 10% more powder capacity, and some small improvement in velocity. Both versions of the .243 cartridge are good for hunting deer.
Performance
The .243 produces a velocity of 2,960 feet (902.21 m) per second with a 100 grain (6.6 gram) projectile from a 24-inch (610 mm) barrel. Commercially loaded .243 ammunition is available with bullet weight ranging from 55 grains (3.6 g) up to 105 grains (6.8 g), typical bullets being in the 75�90 grain (5-6 g) range.
The .243 has gained substantial worldwide popularity, and commercially loaded ammunition is easy to find on every continent. Along with the .270 Winchester, the .308 Winchester, .223 Remington, and .30-'06, it is among the most popular and widely available of all centrefire cartridges
http://en.wikipedia.org/wiki/.243_Winchester
.243 Win + .243 AI Cartridge Guide
High-Velocity 6mm for Long-Range, Varminting, and Tactical Use
243 Win--Multi-Purpose Precision
If you could have just one rifle to slay varmints, hunt white-tails, shoot paper at long range, and duel in tactical matches, it would be hard to beat the .243 Winchester. This versatile "little brother" of the .308 Winchester is a true triple-threat as a match cartridge, varmint cartridge, and game cartridge. With 115gr DTAC bullets, a .243 rivals a 6.5-284 ballistically out to 1000 yards. Shooting 80-100 grain hunting bullets, a .243 will anchor a buck with authority. Driving the light 55-75 grain pills, the .243 provides the flat trajectory and high impact energy varminters love. As a tactical round, the .243 is one of the best, offering excellent ballistics, moderate recoil, and stone-reliable feeding from a detachable magazine.
The .243 Win excels with a wide variety of powders, and excellent factory-loaded hunting ammunition is available. Off-the-shelf .243 rifles from Howa, Remington, Savage, and Tikka perform admirably with little or no modification. The "improved" version of the cartridge, the .243 Ackley, can do everything its parent can do, with more velocity, and greater brass stability thanks to its 40� shoulder. Among the Ackley variants, the .243 AI is rightly one of the most popular. It is easy to fire-form, and commercial dies are readily available. Barrel life is the downside of both the .243 AI and standard .243. These chamberings pump a lot of powder through a small bore. The result, typically, is rather short barrel life, sometimes less than 1500 rounds. A few folks have been experimenting with the use of very slow, cooler-burning powders. There is some evidence that the use of super-slow powders, combined with modified cleaning regimens, can result in significantly enhanced barrel life.
Brass--An Abundance of Good Choices
.243 Win shooters are fortunate as Lapua, Norma, and Winchester all make good brass for this caliber. We've shot all three brands. The Lapua and Norma both yielded excellent accuracy, and both brands were very consistent weight-wise. The primer pockets did stay tight a bit longer with the Lapua, and the neck tension stayed more constant after repeated firings. Since Lapua .243 brass is usually less expensive than Norma, Lapua is our first choice. But if you find some Norma .243 cases at a good price, don't hesitate to buy them. You may have to adjust your load a bit as the Norma we tried had slightly higher H20 capacity than the Lapua brass.
Domestic (Remington and Winchester) brass is significantly less expensive than Lapua or Norma. If you sort the cases by weight and clean up the primer pockets and flash holes, Win brass can shoot very well indeed. Winchester would be our first choice if you need large quantities of brass, or are shooting tactical matches where it's common to loose brass in the weeds. One Midway user observed, however: "[I prefer] Remington brass over Winchester, due to the different internal volume of the brass. Since the internal volume of Remington is smaller I seem to get more consistent results from both the chronograph and down-range performance."
For varminters, the Sierra 70gr Blitz-King and Hornady 75gr V-Max offer a good combination of accuracy, BC, and explosive impact on target. The Berger 80gr Varmint bullet is exceptionally accurate but doesn't impact as explosively on target. For coyotes, the 80gr Nosler Ballistic Tip and Hornady 87gr V-Max both buck the wind pretty well and hit hard. For small to medium-sized deer, Sierra recommends its 85gr HPBT GameKing for soft-tissue shots out to 200 yards. Where deep penetration and better weight retention is required, you need bullets like the Nosler 95gr/100gr Partitions, Remington 100gr Core-Lokt? SP, or the Sierra 100gr SPFB Pro-Hunter. Click Here to download Nosler Partition Video (requires QuickTime).
Hunter and outdoor writer Chuck Hawks notes: "When using the .243 to hunt medium-size big game animals, bullet selection is paramount. Rapid (but controlled) expansion is very important, as the small diameter 6mm bullet has little shocking power if it does not expand and expend its energy inside of the animal. Two bullets in the 90-100 grain weight range that have earned a good reputation on medium size big game animals are the Remington Core-Lokt and Nosler Partition."
.243 Win For Tactical Comps We asked GA Precision's George Gardner why he chose .243 Winchester for his Tactical Comp Gun. He replied, "Why would I run anything else? Think about it. I'm sending a .585 BC 115 at 3150 fps--that'll shoot inside the 6XC and .260 Rem with ease. I'm pretty sure I have found the Holy Grail of Comp Rifles. There are no brass issues like you can get forming .260 brass. I don't have to worry about doughnuts, reaming necks--none of that. And the choice in brass is great too--run Lapua if you want max reloads and great accuracy. Run Winchester if you're on a budget, and so you won't cry if you lose some cases in a match. I can get 10-round mags, and feeding is 100% reliable, since the case is identical to a .308 except for the neck. Accuracy-wise, I don't think I'm giving up anything to the .260 Rem or the 6XC." We then asked George if he'd considered using a .243 AI instead: "Yeah, the cases look cool with that 40� shoulder, but I think the standard .243 feeds a little better. And I don't think I really need the extra performance of an improved case. Run the ballistics for my load--115 moly DTAC at 3150 fps. You've got less windage than a 2950 fps 6.5-284, with cheaper brass, cheaper dies, cheaper bullets, and less recoil."
http://www.6mmbr.com/243win.html
.243 Ackley Improved--More Velocity, Less Case Stretch
by Bob Blaine, Sinclair International
Parker Ackley reluctantly developed the .243 Ackley Improved ("AI"). Ackley finally gave in to his customers' requests to develop the .243 AI. He had always felt that the .243 Winchester was already an improved configuration, but he did say that the best thing to be gained by improving the .243 Winchester was to substantially reduce the case-stretching problems. The .243 Winchester parent case has always stretched brass, almost as bad as the Swift. Even though you get more velocity with the improved .243, I've also found that the improved version gives a bit more throat life than the parent case does.
The .243 AI delivers more velocity by virtue of enhanced case capacity--roughly five grains more H20 capacity than a standard .243 Winchester. The .243 AI has a water capacity of approximately 57 to 58 grains, compared to 52-53 grains for the standard .243 Winchester.
Fire-Forming
As always, fire-forming is done by one of two methods. Most of you will fire form the brass with loaded .243 Winchester. Ackley always said to use factory loads, or reload equivalent ammo to have a "snappy" load to form the case out properly. You never want to use a reduced load to form with, since you need the pressure to form properly. If your rifle is chambered properly, you should feel a slight amount of resistance as you close the bolt on a new piece of brass. If you do not get this "feel", you may need to seat the bullets out to .010" to .015" into the lands to make sure that the base of the case stays in solid contact with the bolt face. The fire-forming method I have been using more lately employs medium burn-rate pistol powders and Cream of Wheat. I will start by loading about 10 grains of SR4756 or Unique into the case, and then I fill the case up to the body shoulder junction with Cream of Wheat. I will then take a large pinch of polyester filler, which can be found at any fabric supply store, or sewing department, such as at Wal-Mart. I will then take the pinch of polyester and load it into the case so that it fills up the shoulder area of the case effectively making sure that the filler is held securely over the powder for fire-forming. During the fire-forming, I like to dry brush with a nylon bore brush every 10 to 15 rounds. This removes any loose debris from filler that has accumulated. [Editors Note: Do NOT seat a bullet using this "Cream of Wheat" method. You can cap the case with a bit of wax to keep everything in place. However, Bob finds the wax is not necessary if the polyester filler is placed securely.]
Recommended Loads
I'm often asked, "what gunpowder do you recommend"? I generally recommend medium-slow or slow burn-rate powders for the .243 Ackley. I have found, with my rifle, that H414 is pretty much my first choice for use in the .243 AI. H414 tends to give me great accuracy, with good velocity. Saying this, I have tried many other propellants and have found the following powders to be worth looking at for your needs: AA-2700, H414, H4350, VV N150, VV N550, VV N160, VV N560, RL19, H4831sc, and VV N165, to name a few of the powders that I have tested over the years.
Different Reamers, Different "Improveds"
One thing that you need to watch for is what version of the .243 Improved that you have. This depends, for the most part, on whose reamer you will be using for the chambering of your barrel. It is easy to determine if your .243 Improved is the .243 Ackley Improved, or the .243 Winchester Improved. If you have the .243 Ackley Improved, the shoulder-body section will measure .460" dia. at this point. If you have the .243 Winchester Improved, the shoulder-body section will measure .455" diameter at this point. Both cartridges have the 40-degree shoulder. I have used both versions and found that you can use any data developed for either version interchangeably.
The .243 Ackley Improved is one of the best long range varmint rounds going, and can add some extra punch for your light big game rifle as well. One would be hard pressed to ignore a cartridge as versatile as the .243 Ackley Improved.
Matt's Screamin' Yellow Ackley--The Need for Speed
.243 AI Speed Demon
In a long-range varmint rifle, speed kills. Ultra-high velocities deliver flatter trajectories and more explosive hits. And that's where the .243 Ackley really shines. While we don't advocate "pushing the limits" with factory actions, Matt Bianchini has explored the upper limits of .243 Ackley performance with his Farley-actioned long-range rig, fitted with a 29" Lilja 3-groove, 8-twist barrel. Using a stout load of Reloader 25, Matt's "Screamin' Yellow Ackley" has topped 3340 fps with Clinch River 106s. That is serious speed for heavy 6mm bullets. This shows a well-built .243 AI leaves Dashers and 6XCs in the dust when it comes to pure velocity.
Dies and Reloading Gear
Since the .243 Win is such a popular cartridge, all the major die-makers offer reloading dies. It's hard to go wrong with a Redding Type 'S' Full-length bushing die--item 77114 for the standard .243 Win and item 77420 for .234 AI (40?). This will both resize the case (and bump the shoulder) as necessary, and allow you to adjust neck tension with bushings. Alternatively, you can go with a body die (item 75114), and a separate neck bushing die (item 71114).
If you load primarily one brand of bullets, another slick set-up is to buy a Forster full-length .243 sizing die, and then send it off to Forster to have the neck honed for your desired amount of tension. Forster charges just $10 plus shipping for this service. This elegant one-pass sizing solution produces very straight rounds with low run-out. We also believe that doughnuts (in the neck) form less readily if you full-length size with non-bushing dies as opposed to using bushings. Bushing dies leave a little bit of the neck unsized, and that's where the brass can build up.
For bullet seating, both the Redding Competition Seater (item 55114) and the Forster Ultra-Seater (item U00034) work great for the standard .243 Win case. If you shoot a .243 Ackley, Redding's .243 AI Comp Seater (item 55420) costs quite a bit more than the standard version and Forster doesn't list a .243 AI seater in their catalog. However, you can just run your chambering reamer into the inner sleeve of either die to fit the Improved case.
If you want the "Cadillac" of production seater dies for the .243 Win, order the Wilson Stainless Micrometer seater (item 50-1114S) from Sinclair International. Costing only a few dollars more than a Redding Comp seater, this die is a joy to use, providing very positive control over bullet seating depth. When used with a quality arbor press, the Wilson offers unrivaled "feel" for bullet-seating force. This can help you monitor neck tension, one of the most critical factors in maintaining low ES and SD for long-range accuracy.
http://www.6mmbr.com/243win.html