280 Ackley Improved

[longrangeind]

I've heard wonderful things about the 280AI over the years and decided to build one. I've had a terrible time trying to work up an accurate load. I can get a group at 0.740 @ 200 yards and then the same load will open up to approximately 4 inches or greater on the next group with the same load. Very inconsistent groupings.

Remington 700 Action
Schneider Barrel 1/10
Nosler Brass
I've run H4831SC, H1000 and RL23 with 168 VLD's. Mixed results. All will produce a decent grouping on one or two groups at best and then open up. Very inconsistent.

I thought this round would fill a void between the 270 and 300 Win Mag but spent more time on it than both calibers listed above.

Anyone else run into inconsistencies with the 280AI?

 

[Buttermilk]

Twist rate is a bit slow for 168 Bergers. 1:9" twist would be better.

 

[longrangeind]

Buttermilk, Thank you for that info. I was beginning to question the twist rate. So maybe I should run 160's?

 

[cowboy]

Buttermilk, Thank you for that info. I was beginning to question the twist rate. So maybe I should run 160's?

My son and I both have 280AI's with 1/10 twist barrels and have shot the Berger 168 VLD's hunting bullet for years. After Berger updated their twist recommendations they lowered the VLD hunting bullet to a 1/9 twist recommendation from what had always been a 1/10 twist minimum recommendation. Bergers 168 Classic Hunter was listed at 1/10 twist when they finally hit the market - I tried them and had very noticeable improvement in consistency. The little I gave up in BC was well worth the improved consistency in accuracy.

I live at 3600 ft. Elevation, hunt up to 9000 ft and ran my 168's at 2840 fps. My son lives at a higher elevation than I and pushed his just over 3000 fps and has never had a problem with consistency with the VLD hunting bullet and he has no need/desire to switch to anything else - same gunsmith, same reamer on both rifles. I just think he stabilized his better with more velocity and higher elevation.

We both use Nosler brass, I use 210M primers, son uses 215M primers. Both rifles are starting to get close to their barrels life span and they'll get 1/9 twist barrels when it is time.

 

[longrangeind]

Cowboy, thanks for your reply.

I've been running Nosler Brass, Fed 210M and velocity is anywhere from 2700 - 2900 depending on powder and charge of course. I live at 1200 ft elevation and 2900 is max velocity as I have pretty bad pressure problems.

So; if I understand your post correctly; your son is shooting the 168 VLD's and you are shooting the 168 classic hunters? Is that correct? I was going to pick some up tomorrow and give them a run to see how they group.

Have you heard anything about the Nosler Accubond Long Range 168's?

 

[cowboy]

Longrangeind: Going to send you a PM.