223 replacement barrel

[wch]

Two questions, actually:
1. I have a Kimber 84 in 223 Rem with a 1-12 twist and want to replace it with a faster twist, say 1-9, for heavier bullets. In your experience would this twist barrel still stabilize 55 grain bullets?
2. Would you rechamber to 223AI, for the added velocity?
I would use the rifle to hunt for varmints up to coyotes, and as a pleasant paper puncher.
Thanks.

 

[shootsanything]

I have a CZ527 with a 1:9 twist and it works great for anything from 40 to 69gr - so I say go for it. My standard load is 55gr balistic tips and they work great to 500+ yards.

If I were to rebarrel I would likely go AI - 22-250 velocity and .223Rem case and a lot less powder. In a bind you can always use off the shelf .223 which is super if you run out while shooting away from home.

 

[15Tango]

I'd go AI if given the choice, less brass trimming and a bit more performance. A 9 twist has always worked for me with bullets up to 75 grain but I've been trying an 8 twist lately and it seems like it might be a bit more accurate with the heavy bullets and an 8 allows use with 80 grain bullets if you want. That twist will work fine with 55 grain bullets as well.

Wayne

 

[ChuckMiller]

As mentioned the 1-9 will work fine with 55's, that AI case configuration will not feed from a Kimber 84 internal mag. Unless your quick on singleshot reloading while a coyote is beating it into the next county stick with the std 223. What your gaining in speed is just not worth losing the repeater function of that rifle.

 

[SS427]

My 1:9 twist .223 shoots 52/53/55 grain Sierra and Nosler bullets with greater accuracy than the heavier bullets, so lack of stability is not a factor.

I would not rechamber to AI for the velocity but I would for the increased case life. If like said above they won't chamber from the mag, I would not do it though. Also, if I thought I might sell the gun in the future, I wouldn't do it either. Easier to sell a straight .223 locally than a wildcat of any sort.

 

[wch]

Well, all of you have certainly given me food for thought.
Seems as if the best bet is to rebarrel in standard chamber, but with 8 or 8.5 twist.
The point about resale is particularly noted.
Does anyone know if a dummy round is available for me to check feeding?
Thanks.

 

[k80skeet]

My Savage LRPV 223 1 in 9 twist will shoot anything from 40gr to 77gr under 1/2" and the 69gr Seirra Match Kings, 70gr Berger VLD"s and 73gr Berger Match will all shoot sub.2's so it likes the 69's-73's the best.

 

[ReedG]

Hate to see you miss the joy of an AI because of the Kimber magazine. Not sure what Kimber has in there but I'd take a close look at smoothing the path or something. The .223AI is a super cartridge.

By the way, never build a rifle for it's resale value to someone else. Build what you want and enjoy it.

 

[bumtownbutch]

I have a Kimber 84 that I have rebarrelled to 223AI; maybe, it's my rifle, but it feeds fine from the magazine.

 

[Larryh128]

The 55gr bullets work great out of my 1-8 twist. If you want a couple dummy rounds loaded, send me a self addressed , stamped padded mailer & I'll make you a couple.

 

[Ackman]

Two questions, actually:
1. I have a Kimber 84 in 223 Rem with a 1-12 twist and want to replace it with a faster twist, say 1-9, for heavier bullets. In your experience would this twist barrel still stabilize 55 grain bullets?
2. Would you rechamber to 223AI, for the added velocity?
I would use the rifle to hunt for varmints up to coyotes, and as a pleasant paper puncher.
Thanks.

1) For varmints up to coyote, 50's and 55's are just fine. There's no need to go heavier, and faster than 12 twist is unnecessary. So no need to rebarrel unless you've just gotta' have a 9 twist.

2) However well the barrel shoots as a .223, as a 223AI it'll shoot the same only 150-200fps faster. The 223AI is a great cartridge and worth doing.

 

[artbosco]

Question: Would you rechamber to 223AI, for the added velocity?

Answer: No. I wouldn't.

Whenever you increase velocity down a small bored barrel, you increase barrel wear, at a faster rate.