.223 AI worth it?

[dan__olson]

Hello,

I have a Savage 12FV that has always been a really good shooter. I'm embarrassed to admit it, but I let it sit a while too long in a high humidity (think Iowa in the summertime) environment, and the chamber developed enough surface rust to not allow a round to chamber. I was able to clean the chamber back to bare metal, as well as giving the bore a good cleaning (no rust appeared on the patches, so the fouling must have protected the bore from damage) and loaded some light loads initially looking carefully for any signs of over pressure or anything out of the ordinary. I didn't see anything that alarmed me, no flattened primers, cratering, etc. So I proceeded to work my way back to my accuracy load watching for signs of pressure all the way up, and found that the rifle was just as accurate as before, so I think I dodged a bullet this time around and my mistake doesn't appear to be too costly. However, with the chamber in the condition it is in, and with the extremely long throat that the rifle has, I thought it might be a good idea to set the barrel back the get the throat shortened up as well as clean up the chamber. Now, my question is, is it worth it in terms of brass life, etc. to have it rechambered in .223 AI at the same time? I don't really need the velocity by any means, since the rifle loves Speer TNTs, and I'm alreay pushing it with the 1 in 9 twist the barrel has, but I have heard that the AI is easier on brass. How about accuracy compared to the standard .223? Obviously that's going to be dependant on the gun and load combo, but I'm just speaking in general. Thank you all for your time.

 

[mr.trooper]

22-250

 

[dan__olson]

Certainly a plausible option, but I'd like to stay with the bolt face I've got and I've got .223 brass already and would like to stay with that. Thanks for your reply.

 

[rcmodel]

I wouldn't bother.

Do you shoot thousands of rounds, to the point where brass life would become a cost factor?

Even if you do, the barrel will be shot out before you save the cost of rechambering it on brass life alone.

rc

 

[dan__olson]

Thanks for your replies, guys. Maybe I should rephrase my question a little. Based on the condition of the chamber and the excessive freebore, I would like to set the barrel back and have the chamber recut. Based on this, I just wonder if it would be worth the trouble to rechamber in .223 AI since the cost is going to be the same either way, and if there is some advantage to be gained by going to the AI aside from the increased velocity, then I would be interested in chambering the rifle in that caliber if only for the sake of having something unique that can still shoot factory ammo if the need arises. As an aside, being a machinist for the last 8 years and always having an interest in doing rifle work but never a need or opportunity to do something like this, I think it might be an interesting learning experience doing it myself (with advise from an experienced gunsmith, of course, I have no intentions of blowing myself up) I understand the basic procedures and have done similar operations in the past, just never cut a chamber, as stated earlier. Actually, perhaps this thread has moved in a little different direction and maybe should be moved to the gunsmithing section? Please feel free to do so if you see fit, moderators. I realize that asking these kinds of questions with my low post count probably doesn't look real good either, but we've all got to start somewhere, I suppose. Thanks a lot for the help so far guys, and hopefully I am a little more clear with what I am asking now.

 

[esheato]

I have a 223 AI.

While the velocity increase is an admitted meager 7%, it does make a difference. I'm pushing 40 grainers at 3800 and can reach 4000 fps without trying too hard.

The other fantastic thing about the AI is that brass doesn't grow. Due to the nearly straight case body and sharp shoulder, case trimming is practically not required.

Lastly, I like having something a bit different than everyone else and in a pinch I can revert back to boring 'ol .223 Rem.

It looks to me like you have enough reasons to do it...

Ed

 

[Vern Humphrey]

Have you checked the pressure of those loads?

The rule of thumb is that a 4% increase in case volume will yield a 1% increase in velocity -- so a 7% increase would need a 28% increase in case capacity -- assuming equal pressures.

Normally, the AI chamberings do not yield much (if any) velocity increases at SAAMI pressures.

 

[jester_s1]

I don't see why you wouldn't go to AI if you aren't going to have to pay more. As stated, it makes reloading easier and cheaper and gives a small performance boost. You may even consider having the throat set at minimum dimensions for the bullets you like too.

 

[Art Eatman]

You say that it's just as accurate as before, and you say that you don't need added velocity, so why bother doing anything at all? "If it ain't broke, don't fix it."

 

[Vern Humphrey]

Be careful, Art. I think there's a rule against introducing common sense into a thread.

 

[dan__olson]

Art, I have had the same thoughts too I guess it just bugs me that the chamber is not as "perfect" as it once was... this is a factory rifle after all, so it's not like it was neccessarily perfect in the first place. More than anything I guess maybe it's just an interesting project... I like to tinker, but I defininatly do understand that I could end up with a worse result than what I've got now and that is obviously not a good thing Thanks for all the replies, guys, you've been a lot of help so far.

 

[Vern Humphrey]

Savages are pretty cheap to rebarrel -- if you have the tools, chamber gauge and so on. I suspect a local gunsmith could screw on a new barrel for minimal cost.

 

[esheato]

Vern..you're right. I used the wrong term. My AI returns an increase of approximately 7% case capacity, which would in turn provide less than 2% increase in velocity according to your rule of thumb.

Pressures at 3800 and even 4000 fps are not dangerous according to QuickLoad or my rifle. I've shot nearly 2000 rounds at the 3800 fps velocity without a problem.

For the record, 223 AI always gets beat up for the end not justifying the means. I purchased a custom rifle initially reamed for .223 AI, so there was no smithing required.

Performance is spot on, PDs explode nicely and I don't have to trim brass. It's what I was looking for.

Ed

 

[Vern Humphrey]

Oh, there's nothing wrong with the AI rounds. There may well be something to the proposition that the sharper shoulder permits more precise headspacing and contributes to accuracy.