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exbiologist's picture
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What would you do now?

So, recently learned how to conduct an optimum charge weight test/pressure ladder/whatchamcallit. I decided that would be a good thing to try and had been wanting to do some more load development with the 130 Accubond in my .264 Win Mag. Figured it would be a good deer load and should work well for cow elk.
Yesterday was pretty dang windy here in Colorado, but I'm not certain the wind was to blame. Previously, I tried several powders and had been pretty happy with the velocity with 66 grains of Win 780 with the 130 Accubond. The only group I ever shot with it was 0.6 MOA, 3 shots at 100. But for whatever reason, I left that load alone and never played with it again. Velocity was around 3250.
This is from a year ago and why I tried this combo again:

So yesterday I load up 3 rounds each around in half grain increments around 66 grains: 65.5, 66, and 66.5. I then load up .1 grain each for 11 total shots from 65.5 to 66.5 to see shoot a ladder group.
I don't know what to make of the results:
65.5 was around 1.6 inches and a bit of a flier to the left (20 mph wind was left to right), the two closest holes were were about an inch apart.

66 was a little larger at about 1.8 inches with two of the holes within an inch, and again a flier to the left by nearly an inch (winch blowing to the right).

66.5 was about 2 inches with 2 touching and 1 1/2 inches to the left.

Then I did the ladder group, which is incredibly hard to decipher. It looks to me like there is a node around 65.6 or 65.7 grains, but it was totally inconsistent. I have no idea what to make of it.

I do not believe the wind played a big factor in the groups, as the .270 I was shooting did not suffer from the same problems. Thankfully, I've kept many of my targets from the last few years as reference. Sure enough those Accubonds had thrown fliers to the left before with both N165 and 780, but no other bullet or powder combination had done so to a meaningful degree.


Next problem, what appears to be the making of a decent accuracy node puts velocities down into the mid to upper 3100 fps range, which is not acceptable. That's .270 country, not a .264. 3250 to 3300 is my goal with this load. Book max is 67.0, and that'll do 3400, but the pressure signs are not acceptable to me.
So what the hell do you make of all this?
What do you blame for the fliers to the left? Hard for me to blame anything but the bullet.
Do I need to try a new powder also? It doesn't seem like I can get the accuracy and velocity combination that I am after with this pair. Use something a little slower, like RL 22, MagPro, 7828 or N165? A lot slower, like H1000, Retumbo, Magnum, RL25 or US869?
Should I just call a do-over and do it again on a calm day at 200 yards for a little more separation?
Do I need to be shooting 5 shot groups to find any real differences?
Not sure what my next step should be here.

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Location: Upper Peninsula of Michigan
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Re: What would you do now?

I would suspect wind played a role, as no wind is entirely consistent in velocity (waxes and wanes). It also could be that that bullet does not respond to that particular powder. I have always had good luck using the Nosler manual loads that they mark as most accurate in a given powder. I chose loads that Nosler says are most accurate at the velocity I am seeking, as my starting point and rarely need to deviate from that charge weight. In my experience, the type of powder DOES make a big difference in group size. I have never loaded the .264 so I can't help you there.

exbiologist's picture
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Re: What would you do now?

Thanks, I think I'm just gonna say "screw it" with the 130 Accubonds. I've got accurate loads with 100 grain Ballistic Tips for antelope, and 140s that I've used on elk and deer. Ought to just stick with those, maybe tweak them a little, but I know I've got a few things that work. You know how reloading is, it's addictive and you're always in search of just a little better, when the first thing you tried after all the research was probably good enough.

WesternHunter's picture
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Re: What would you do now?

Given the extream gusty high winds that we had last week I'm surprised that you are not surprised that had anything to do with it. Many times incriment increases in 1/2 grain charge can have dramatic affects to grouping, but I sure would not expect consistant results in the gale force gusting conditions we experienced last week.

There are many more things that can affect groups as well - trigger pull, screws being loose on the action or scope mountings, too hot a barrel, etc. Even the shooter just not feeling in optimum condition on that particular day can really affect things. I've often shot on days that I was exhausted, fatigued, or had more pressing issues on my mind. The results were less that I would have liked to see. Equipment and ammo is only a part of the equation.

SoCoKHntr's picture
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Location: Pueblo Colorado
Joined: 12/18/2006
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Re: What would you do now?

I've shot in some fairly stiff for shooting winds ten to fifteen or more mph and with loads that I knew shot well still grouped fairly consistently with the wind generally moving the entire group not just causing an errant flier. As you said the 270 wasn't performing bad in the same winds. From your groups I'd say some component was off in your recipe. I get groups like that when my recipe isn't to the guns liking.