i am trying to find out what is a better cartridge the 243 ai or the 25/06ai. I've asked this a couple of times on different web sights. most went with the 243ai. whats your openion. i'm planning to buy a tikka to convert with a kreger barrel.
thanks for your openion

Neither. Straight 243 in an 8 twist for the 105 class bullets.

Next question.

What do you want to do with it?

Deer?
Varmits?
100 yd benchrest?
500 yd?
1,000 yd?

Of the two the 243 is the better.

If you want a 6mn. I'd take a hard look at 6mm Creedmoor.

It depends entirely upon what your purposes are. Long range guys like 6mm better than .257 because of the greater choices of high BC bullets available in 6mm. If you don't buy into hunting with bullets chosen for BCs and you stick with the traditional bullet performance paradigm, then the .25-06 AI is probably your ticket. If you want to bang on steel at long range then the .243 AI would be the better choice.

243 would be my choice for the 90-115 gr bullets. No need in going the AI route if you are going to run light bullets as you won't see much velocity increase over the parent round unless you run over pressure. The AI shows more advantage with heavy bullets in my experience. The 25 is kinda a crap shoot as the 257 Weatherby does what a ackley 25-06 would with no forming of the brass.

Depends on the usage. Both would be good hunting rounds for strictly hunting my vote would be 25-06, like others said for target the 243. Biggest advantage for both in the AI form is brass life with less case trimming.

Another AI that offers more case capacity in 6mm is the 6mm Remington AI.

I'd think you'd need a 24" barrel - or longer- to justify enough additional MV when AI'ing any caliber...and all Tikka T3 Non Mag's are 22" barrels...but then I could be wrong too, since I've never had anyone delve into the AI minutia to tell me the +/-'s of barrel length X's AI'ing.
Ron

If the barrel is new go with the std chamber. Shoot it 2500 to 3000 rounds have the barrel set back a couple of turns and then go with the AI. You will get almost double the barrel life and in most instances you just need to clean up the throat area. Lots of guys go with the 243 then later on open it up to 6mm Rem and it will do the same thing.

Straight 243, readily available reloading components and a great caliber.

You don't need any more barrel than the parent round needs. My 7mm -08AI uses a 22" barrel with no ill effects.

my main interest is antelope and mule deer. I wanted a light rifle [ tikka is 6.3 pounds] that could reach out to four houndred yards of so. I was planning to get a 243 and shoot it for a while than change the barrel to 24 or 26 inch in the 243ai.
I was told so far that you can get between 200 and 300 fps more using either 90 or 100 grn bullet. you can reload the cases a lot more due to the shoulder. that it catches up to the 25/06 at about four houndred yards.
I have about 300 cases of 243 right now that were shot once. I would just have to fire form them.

You won't gain near the 200 to 300 fps going to an AI round. If you compare the standard 243 Win to a 243 AI with the same bullet weight, you may gain about 75 to 100 fps more. If you reload a lot already and are familiar with the concepts, then an AI would give you the extra speed. But it will take A LOT more brass prep and the cost to fire form the brass. If you do not reload now, I'd stick with a standard 243 Win and learn to reload with it, since it's a pretty easy round to reload. No animal will know the difference between a 243 Win or the AI going 75-100 fps more with good shot placement. Spend the extra time and money on shooting more of the standard 243 Win. Most shooters, what I call, "Geek Out" over the small things, instead of working on the big things, like learning how to dope your rifle for long range and learning the wind.

I saw no reason to do the AI. I built a straight 243 and I am shooting the 105 berger at 3050 from a 26in barrel. I didn't want to the extra work for the AI and I am just happy with the regular 243.

Walter

50-100 is typical for gain with the lighter bullets while 75-150 is normal for the heavier bullets in a AI off the 308 case. Forming brass is a simple process that doesn't take hardly any time. Besides the fact of not having to trim brass near as often there is a lot of gunsmiths that think the AI will give longer barrel life since the shoulder angle helps direct the gases more to the center of the bore and off the throat. Here is a link to a page with some good info on the 243 AI.

http://www.6mmbr.com/243Win.html

If your having a barrel made how about a 6mm rem with a custom twist to your liking? I believe you'd get even a tad more velocity or at least equal velocity to the 243ai and you wouldn't have the case prep of the ai.

.257 AI is the best of the bunch. But its not worth it. Took me 10 years off and on to find the right load that is pretty much equal to the the .260. Really. Found a tack driver load but gave up on it during the process several times. Custom rifle with a Hart barrel. VERY picky. It's very tough to beat a .260. Opinions may vary.

Get a 257 Weatherby and call it good

I have a 257 weatherby. I'm looking for something as good but lighter than 9.3 pounds and left handed

In my opinion the choice of quarter bore projectiles has been limited. That may have changed of late.

Either a 6.5-08 (aka 260 Rem or a 6.5-06 would be my choice. Oh yea, I had a 6.5-06 till I let my son claim it. Guess I can get it back.
TC

I would do 6.5-284 on a long action over a 6.5-06. They are the exact same case capacity but the short fat column of powder typically yields better accuracy.

Agree with you on that choice Dee. Have a 6.5-284 in a long action and it really works nice. Haven't shot mine much in the last year but it did ok. 1 1/8 3 shot group @ 325 yards plus a few dead critters deer, hogs and yotes.

^^Yup^^

For those that mentioned it. No way will a quarter bore hang with any 6.5mm.

When you start getting into the 400 yard mark and beyond, BC is what gets it done not muzzle velocity.

Belive it or not a 140 gr 6.5 mm will deliver more foot pounds leaving at 2800 fps than a 175 SMK or 178 A-max out of a 308 Win.

OP, if you want a 243 keep it a regular 243. As Chad said, shoot often, learn to read wind and compensate for it and you will be lethal.

I haven't pulled up any data from 25-06 but i bet the 6.5 has a wind advantage before 400.

I'd bet the same way.