Quick Question about 223AI

[squirrelsnpr]

I see alot of people claiming they are getting about 2900-3000 FPS while shooting the 75 A-Max's in their 223AI. I was considering going with the chambering, but I am getting an average FPS with my plain 'ol .223 and 75 A-Max's of 2930, with BL-C2. Is the 2900-3000 FPS with 223AI a conservative figure?

 

[762willdo]

.223AI 18" 9 twist rock creek, 27 grn's. R-15, CCI450, 77grn. SMK= 3000fps
shoots litle tiny bugholes (yes i can drive it faster but why?)

 

[alf]

Plain 'ol .223

17 1/2"(yup) Rock 1-8" twist

R-15 - 75 A-Max - Rem 7 1/2's - 2905fps at 65 degrees

 

[squirrelsnpr]

I read the .223 page linked to the home page here and did see that they said the 223AI gets more FPS with the lighter bullets. For my application, shooting 75-80 grainers, I don't see a point in going with the AI version. Do you all think the standard .223 will get me consistant kills on small varmints out to 400-500 yards, granted I use top quality components and pay attention during reloading? This rifle is going to be built on a Savage action if it makes a difference.

 

[Spook]

I see alot of people claiming they are getting about 2900-3000 FPS while shooting the 75 A-Max's in their 223AI. I was considering going with the chambering, but I am getting an average FPS with my plain 'ol .223 and 75 A-Max's of 2930, with BL-C2. Is the 2900-3000 FPS with 223AI a conservative figure?

My best guess its an accuracy node for that bullet rather than a velocity limit. The next one I've found for the 75Amax was 3450-3600 using a 22-6mm Rem.
How many reloads before trimming with your 223 using 75's @ 2930?
I'm shooting 80 gr Amax very near 2975 in my AI with no brass growth.

 

[squirrelsnpr]

I usually trim after each round. I dont get alot off the ends but some. I did also see this advantage on the .223 page. Does the brass really last longer?

 

[acloco]

Recorded numbers off of my chrono with 223 AI, 222 Mag AI, and 22/6mm AI. Work up your OWN loads...cannot guarantee YOUR safety with MY loads.

223 AI
5 3311.1 26.2 h4895 55 gr vmax
6 3363.4 26.4 h4895 55 gr vmax
7 3392.3 26.6 h4895 55 gr vmax
8 3399.6 26.8 h4895 55 gr vmax
9 3437.7 27 h4895 55 gr vmax
10 3423 27.2 h4895 55 gr vmax
11 3463.5 27.4 h4895 55 gr vmax
12 3468.9 27.6 h4895 55 gr vmax
13 3496.4 27.8 h4895 55 gr vmax
14 3520.9 28 h4895 55 gr vmax


SHOT VELOCITY h4895 69 Nos
1 3115.2 25
2 3014.2 25.2
3 3011.7 25.4
4 3039 25.6
5 3076.2 25.8
6 3117 26
7 3126.7 26.2
8 3152.5 26.4
9 3169.7 26.6
10 3194.4 26.8
11 3247.9 27
12 3254.6 27.2
13 3279.7 27.4
14 3295.3 27.6
15 3346.1 27.8

SHOT VELOCITY h4895 75 amax
1 2948.3 24.6
2 2948.3 24.8
3 3015.8 25
4 3008.4 25.2
5 3061.7 25.4
6 3073.7 25.6
7 3079.6 25.8
8 3109.1 26
9 3167.9 26.2
10 3155.4 26.4

SHOT VELOCITY H4895
1 3129.3 75 Amax 26.4
2 3141.8 75 Amax
3 3135.5 75 Amax
4 3137.3 75 Amax
5 3287.5 69 hpbt 27.8
6 3316 69 hpbt
7 3295.3 69 hpbt
8 3295.3 69 hpbt

SHOT VELOCITY H4895
1 3287.5 69 HPBT 27.8
2 3302.2 69 HPBT
3 3293.3 69 HPBT
4 3285.5 69 HPBT
5 3297.3 69 HPBT


222 Mag AI with 80 gr AMax

STRING 07
SHOT VELOCITY benchmark
1 3033.2 25.5
2 3034.9 25.7
3 3056.7 25.9
4 3070.2 26.1
5 3064.3 26.3
6 3108.2 26.5
7 3147.1 26.7


22/6mm AI

STRING 02 7/26/2008
SHOT VELOCITY RL 19
1 3745 75 Amax 49.5
2 3751.4 50
3 3812.1 50.5
4 3824 51

 

[squirrelsnpr]

Thanks ACLOCO for the real numbers. 3100 FPS with a 223AI and 75 A-Maxs seemed more like what I was thinking. Hows this combo shooting for you?

 

[acloco]

Very good. Just work up your loads after fireforming your brass.

...and fireform your brass in the field...the accuracy is excellent when forming cases as well.

 

[squirrelsnpr]

do you use a different load for fireforming? if so, how far off is it from the fireformed brass?

 

[acloco]

For the several powders that I have tried when fireforming brass, prefer to use a faster burning powder like H4198 and 0.5 to 1.0 grains LESS than a max 223 book load.

 

[CanusLatransSnpr]

Aside velocity. One of the great things about the Ackley Improved variants is that they're not so hard on brass. Especially in the .243 A.I. or the 22-250 A.I. A couple of cases that are known for stretching brass pretty bad. They have more to offer than velocity!

Mike

 

[Ackman]

do you use a different load for fireforming? if so, how far off is it from the fireformed brass?

Fireform loads for AI cartridges can be just as accurate as with formed brass. But you still have to find accuracy when fireforming, just like with any other cartridge. How's that done? You could just pick a load and maybe luck out. But the way is to work up to it just like you would with a std. cartridge. Use the best .223 load for whatever bullet you plan to use and go up from there. The AI chamber is larger than a std. 223 and brass expands to fill it, so going lighter on the charge is pointless. I shoot 50's in the .223 case. With a std. 223 my load is 25.5gr and 50gr bullet doing 3635fps. Fireforming the .223AI I started there and best accuracy wound up being at 26.5gr, velocity about 3700. With formed brass it was just a matter of going up slowly from there, the load was about another 1gr. more powder.

Do the same thing when fireforming any of the AI cartridges. When it's time to shoot formed brass you'll be just about there and it'll be easy finding the right load.