This schit is always fhuqking funny! Crack the door just a smidge and every Drooling Dumbfhuqk takes it as ripe opportunity to expound upon their incredible stupidity. Wait long enough and someone will toss ratios/formulas,then Whine about pressures. Hint.
Now if only in fairness,I've either got or have shot every chambering thus far cited and more than a few that ain't been mentioned yet. Hint.
Simply put,the schittier the parent vessel,the better the yield on the literal Improvement. I realize that is far too crystalline for the Paper Hat Brigade to fathom,which just might be the point. Hint.
Delving deeper yet,there can be some very nice mechanical transformations yielded,that enable Precision benefits devoid the parent's abilities(amongst other layers of frosting inherent the change). Read that again,now one more time.
Coming full circle,Boolits matter far more than headstamps and the Coke Bottle glassed Ping Pong Ball Crowd will never realize same,if only because even in their assembled mass...they don't shoot enough to have a single fhuqking clue about anything. That sorta humor ain't to be slighted and is in fact routinely magnificent in both it's volume and splendor. Hint.
To the chagrin of that same "hard charging" crowd,twist rate and throating are key players too. Give a Drooling Dumbfhuqk some bandwidth and they'll espouse something as hilarious as "240Wby",less a single fhuqking clue about the piece of schit chambering,the piece of schit rifles offered in it,let alone their schitty fhuqking throats and schitty fhuqking twist rates. The chambering is easy to slap silly in a short action,with vastly superior brass of vastly superior case design,if only for starters. Though Window Lickers are exceedingly quick to laude noise,fire and recoil...as salve for Ping Pong Ball BC's. Laffin'!
So let's come full circle in regards to the OP. He plainly cites a query in regards of going SAAMI 243 to 243AI and then the Dumbfhuqkery starts flowing freely. Again,because boolits matter more than headstamps and because noone ACTUALLY fhuqking shoots,he is "rewarded" with multiple pages of cluelessness and less any insight. Simply put,Tikka's suck heavy ass in both 243 and 243AI...due simply to their 1-10" twist rate. Tough to get giddy about dumping even modest loot in an OEM spout,that is designed EXPRESSLY,to deny the best boolits available in it's bore sizing. Such things,make "decisions" rather easy,as it's never not about the big peecture. Read that again,now one more time. Hint.
As per chamberings cited,the SAAMI 243Win is simply a fhuqking Monster and that is the most warmest of fuzzies. Procure a 77,Roaring Lion or 700 chambered same and you get a .547BC at 3000fps,as a minimum. Punch it out and you reap some nice internal Ballistic VooDoo which quells ES/SD and are granted another 150fps minimum. Of course I don't know anyone who pulls plug wires on either chambering(de-tuning pressure),but apparently such practices are held in high esteem by the Haybale & Crockett Crowd. Why in the fhuqk someone would shoot one design at higher pressure(s) than the other,is beyond me,but Droolers cited it...so I reckon they do. Congratulations?!? Funny schit!
The 243Win is an easy chambering to ring the bell with,due it's lineage and logistics. It is no thang to gun false shoulders outta the gate,to ring the bell with every press of the trigger. As hinted at prior,the 243AI is assuredly a vessel of greater capacity and it do in fact dupe 6mmRem internals,though in a form that slaps the fhuqking schit outta same. Very easy to set up a 2.815" OEM box(Big Green),to smooch an upper echelon BC 105 and have breathing(throat chasing) room to spare. DBM's are a breeze too,however one wishes to scratch the itch. A light done right 22" 243AI whistlin' 105's at 3200fps,slaps the dog fhuqking schit outta the 240Wby. Read that again,now one more time. Hint.
Cheer up,I've suffered the 6mmRem and 6mmRemAI and both suck ass. Hint.
To only offer a few more HINTS,the best performing .243" will never be one that isn't twisted to shoot the BEST projectiles in it's diameter. Hint. In this day and age 9" is the cusp(depending upon lineal velocity),8" being a sure thing(even in a 20" 6BR) and the ONLY fhuqking way boolits get better...is by getting longer. Please understand that nobody has more disdain for SMK's than I,so D-Tacs are soooooo far offa the fhuqking radar,so as to not even rate their mention. Ooops! Laffin'!
It remains hilarious,that folks shop rifles by headstamps,though nothing matters more than boolits. Read that again slowly,now one more time. Very easy to sort through twist rates and KNOW in advance what will shine brightest and more importantly why. Re-hint. If suffering schit twist,then opt the best rifle. As 1-10" 243Win's go,that is simply a Montucky landslide and rest assured it's throat will smooch it's best pitch and the magbox will nestle same,with a 90 Skinner at 3300fps on the nose and forgivin' wiggle room. Re-re-hint. Now as a not so fhuqking curious aside and despite a .434 G1 BC,that melding will slap the [bleep] dogschit outta all 240Wby Factory Fodder,even though the 240 is assuredly rocking greater chamber pressures. Re-re-re-hint. Funny how it actually works and I mean fhuqking funny!
It goes without saying that The Do Nothing Gang shoots their mouths more than anything else and I've oft wondered just how fhuqking "loud" their Imaginations are,when they fire them?!? Laffin'! If only BC's "didn't matter",that all things were "equal",twist rates are "moot" and COAL were "meaningless". Re-laffin'!
Ignorance IS Bliss and there are some amazingly fhuqking Blissed Dumbfhuqks here. Wow! I personally take great satisfaction in driving a shoulder to headspace in K-Hornet and groove on the newfound velocity(especially via the long rationed stash of 32V-Max at 3450fps in a 20" OEM 77/22 lop/chop/punchout). The 223AI is simply a GIANT Killer and do things all outta proportion to it's modest shadow. A .435 BC at 3100fps+ in a 21" spout,will cover alotta territory(that's what we in the bidness call "gross understatement"). Hint.
The 22-250AI is another PRIZE. You reap Swift case capacity,at a farrrrrrrrr more favorable COAL and with vastly superior brass and case design. Though in fairness,noone has shot more Swift than I. A 23" spout will make an easy 3450fps with same,leaving tace/impact literally staring one in the face,even in a Flyweight(Montucky contour dupe). I don't much care for the CHeetah,if only because I've suffered a few...22-250AI is the threshold in .224". The 250AI is a friendly chambering and to the chagrin of many,it too outpaces it's parent. Mighta heard good thangs about 25-06AI too and the advantage of an extry round in the belly,over the 257Wby and 100 XLC's at 3600fps in a 24". Not that I haven't shot out more than a few barrels in .532" with 100's at 3750fps. Laffin'!
The 284Win and it's spawn came outta the egg very Improvederish in issued guise and one only needs to neck it down,to ring the bell. Have only built rifles in 284,25-284 and 6-284,all less a tinge of regret and all S/A based. A 23" 6-284 will squirt .547 BC's at 3300fps+. Hint.
The 7-08AI will reliably outpace a SAAMI Magnificent Seven and 162's at 2850fps in a S/A wearing a smooch,do not suck. Hell...there ain't even any flies on the 375H&H AI,though I've only had a coupla them. Rest assured a 300H&H won't run with a 30-8mmRemMag nor close,if only because I've them t-shirts too.
I for one appreciate the oblivious humor extolled in these heartfelt replies,as The Do Nothing Gang simply does their "best" and starts talkin' "particulars" and"all" the Imaginary water that's flowed beneath their Pretend bridges.
Don't let the cat get your tongues,nor the couch your kchunts.
You've been led to water and I HOPE nobody partakes.
Laffin'!
