To ai or not to ai my new tikka 223 ranahan

[KyleR1985]

Wife’s 223 cut to 16” factory howa mini - 2800fps with 77’s and lever loaded at 2.4” in LC brass cci450. Several hundred rounds fired through this barrel so it’s stable.

I just brought new howa mini with Shaw 223ai 16.5” barrel to range yesterday. Same load but 2.35” shot 2800fps on brand new barrel. Chamber doesn’t allow loading as long the standard 223.

Case capacity now 32.8 on the one formed case I measured.

Expecting to push 2850+ as is. May throat it to allow 2.5” loading. No idea how much the barrel will speed up after a couple hundred shots.

88’s shot 2700 with lever.

Both bullets about 125fps slower with 8208xbr but I didn’t load as hot as I’m not as familiar as I am with lever.


Everything I tried shot under an inch for 5.


Fun gun to shoot and it weighs 6.5lbs scoped and suppressed.



Thought process behind the barrel: LC once fired sized trimmed chamfered brass is .15c a piece. I can load either powder I have quickly and precisely. I can throw brass away without blinking. Shooting standard 223 in the gun is more accurate than me. Barrel life forever.

 

[KyleR1985]

Fired LC brass 30.5 avg case capacity, gaining 2gr capacity going to AI.

 

[Thegman]

Fired LC brass 30.5 avg case capacity, gaining 2gr capacity going to AI.

My LC measurement was 30.6 grains water capacity, so right there with yours. 2.2 - 2.3 grain increase, minimal trimming, great accuracy, still works with standard 223 ammo...sounds pretty good.

If the AI "rule of thumb" of velocity increase = .25 x powder increase is correct, that's only about 50 fps gain at equal pressures, but some powders, especially stick powders, seem to run out of room before reaching max pressure in a 223 case. In those cases I could see the 223 AI making more than that 50 fps with powders on the slow end of 223 loading.