Now that I have all my variables coming together (NAB 225, Nosler brass, headspace, OAL), my groups are an exciting and consistent as this target. (shot a number of same hole groups as well last weekend)
..I am getting greedy, but down so close to the wire (3 weeks away) for the 10 day hunting trip.
338 Win Mag with NAB 225 71gr at 2738 FPS at the muzzle.
I also tested 9 rounds of the same but made two adjustments (72 gr and adjusted OAL -.004 than the previous 71 gr loads.) 100 yd accuracy dropped to 2" groups.
The question(s)
1. Was it the change in powder or the change in OAL or the change in both that caused me to loose the accuracy?
2. Does the optimum OAL stay the same regardless of the change in powder sizes?
I would like to get a little more power out of my 338 win mag if I can also keep the accuracy.
Thanks
Stevesdl
View attachment 10-13-2010 338 Win Mag 225 NAB 72gr 3.447 OAL0001.jpg
..I am getting greedy, but down so close to the wire (3 weeks away) for the 10 day hunting trip.
338 Win Mag with NAB 225 71gr at 2738 FPS at the muzzle.
I also tested 9 rounds of the same but made two adjustments (72 gr and adjusted OAL -.004 than the previous 71 gr loads.) 100 yd accuracy dropped to 2" groups.
The question(s)
1. Was it the change in powder or the change in OAL or the change in both that caused me to loose the accuracy?
2. Does the optimum OAL stay the same regardless of the change in powder sizes?
I would like to get a little more power out of my 338 win mag if I can also keep the accuracy.
Thanks
Stevesdl
View attachment 10-13-2010 338 Win Mag 225 NAB 72gr 3.447 OAL0001.jpg