243 A.I. bbl life vs 243 Win bbl life.

[243]

I have a Remington model 700 in 243 with about 500 rounds down the bbl and currently thinking of rechambering to 243A.I. What will the benefits be of the A.I?

 

[dcb]

I have a savage with a Douglas 26" 243AI shot mostly 95gr berger molys. at 1000yd. and only got about 850 rounds before the throat moved .150"
with the AI you can expect more case capacity and a slight increase in velocity. the improved case also leads to longer case life.
Dave

 

[243]

Does it have a increased barrel life over 243Win.

 

[dcb]

I think they are fairly close, the AI uses a bit more powder and that equates to hotter loads.
I think the demise for my barrel was the fact that I shot it till its was pretty hot.
If you let the barrel cool down every 5-to-10 rounds it should give you better barrel life.
Dave

 

[243]

Thanks

 

[Ackman]

It'll be just about the same. A std. 243 is semi-improved anyway. Forming it into an AI blows the shoulder forward and makes it steeper, but body taper only changes a little and shoulder diameter is about the same. Case capacity doesn't increase nearly so much as some of the others. But just that modest increase is still enough to push 70's the same velocity or faster than a std. 243 pushes 60's. To me it's worthwhile.

It's been a long time since I shot a std. 243 but it seems like those loads were about 2gr less than a 243AI. That isn't a lot in a case that holds close to 50gr. It's been claimed that a sharper shoulder reduces throat wear. I couldn't say if it does or doesn't. But if so, maybe it would offset the slight increase in powder used.