Is there a way to read groups that a rifle shoots? I am getting different "types" of groups with a 22-250 and a 280 AI but have yet to find the sweet spots. Where is the voodoo and how do you read the signs without throwing chicken bones? I am going mad playing with seating depth and incremental powder changes.

I know your frustration... And that's why I came up with the following load development method:

http://216.219.200.59/cgi-bin/ubbcgi/ultimatebb.cgi?ubb=get_topic&f=13&t=000256

This is based loosely on Creighton Audette's "ladder method," but it provides more useful information, and is not as subject to the whims of the wind and pulled shots as the ladder method is. Further, Audette only sought to find a particular "node" for the rifle he was shooting. He altered the powder charge to get onto a good node. I recommend finding that node only after you first identify the best powder charge for the application at hand. You find the correct harmonic node by seating depth alterations...

Note the follow up posts by various shooters in the link posted above. The load recipe identified there worked very well in various .223 Remington rifles.

Loads developed in this manner should be good performers in the overwhelming majority of rifles chambered for the load in question. As evidence of this statement, I provide this email reply from Paul Box, which he provided when I questioned him as to the whether "universally good load recipes" actually exist:

"Hi Dan,
I agree.There are certain loads in every caliber that will produce a vibration pattern that seems to allow the bullet to leave the muzzle at the same point of that vibration.Usually if a load won't shoot in a rifle that has been known to be a good load in others,there's other problems with the rifle in a barrel being ho-hum,out of round chamber etc.These kind of rifles might shoot something else off the wall so to speak,but likely it'll be an uphill job finding it.Ken Waters made a fair piece of change with this idea in his pet load series.I've given out thousands of loads over the years that have proven to be very accurate in other rifles.You bet it works.
Paul"

If I can help you further, please let me know...

Dan Newberry
green 788

Dan, by sheer luck, I did set up seperate targets although I didn't group them like you did. After reading the thread, instead of worrying about the best group, I placed the targets over the top of each other and held them up to a light. So, my good spot seems to fall between 38 and 39 grains of H380. The aggregate group is in a diamond pattern, 1 1/4 top to bottom 1 inch from side to side. Fifteen rounds, eleven fall in between the widest four. So I guess that would be the place to start, 38gr in .2 increments to 39gr? What do you think? The next round of testing will follow the thread example.
Thanks for your help, Alan

You're bound to find an accurate combination with the H380 in the 22-250. What powder are you using with the 280?

It is a 280 AI and I am trying RL22 and IMR's 4350 and 4831. Some loads show promise and then go straight to hell. It is killing me. I paid good money to have this rifle built and I hunted it once because I knew the shots would be under 100 yds. I really hate buying all these powders and bullets and having no luck. I am going to try Dan's method with the 280 and see if I can't do a better job. The 280AI is an Arg 09, L-Walther match bbl, the action and bolt have been faced, trued, whatever. The barrel and action machining were done by a very reputable gunsmith. I am hesitant to mention his name, primarily because I don't think at this point my reloading should have any reflection on his work. The parts are there, the load isn't. If nothing works I may send it out to have it checked up on eventually.

On both load developments, I would just start out by barely seating a bullet in a dummy case and then closing the bolt on it several times to get an average for your initial seating depth - then work up to a max load at that length. The method posted above will work, but so will this bubba method. I myself like to let the rifle make the first decision.

I'd say that IMR4831 is your best bet for the 280. If you can't seem to find an accurate load with this powder, then I would suspect the bullet first. I would also bet that if you loaded a 150gr RemCL over a full charge of IMR4831, that you'd get an accurate load right off the bat. I'll bet.

I wouldn't even worry about seating depth and fine tuning this early on.

Carnivore,

Just bump up the charge in .3 grain increments since you're dealing with a 40 grain general amount.

Maybe 38.1, 38.4, 38.7, 39.0 and 39.3...

Remember to fine tune for group with OAL (seating depth) adjustments after you've identified the OCW. I would normally just start with a caliber's depth in the case, then load three each of increasing .010" lengths, out to what the magazine will hold. If groups tighten, keep shooting. If they begin to open up, go to the longest variation you have and try that--it's possible that the longest variation will take you onto a good harmonic node of the barrel. If that group isn't tight, it's time to shorten all of the cartridges left in the test by .005" and see how things go. Let me know if this is making sense.
If these .005" shorter rounds get you tight again, it would be okay to test in that direction, shortening by .005" each time and watching for group trend.

Distance to lands is not the holy grail that many believe it to be. If your bullets are loaded straight into the case (little to no runout), they will enter the throat straight.

One of my .223's will shoot 1/4" groups with the bullets seated way deep in the case...

For the .280 AI, what bullet are you going to use?

Dan

quote:

Originally posted by Carnivore:
It is a 280 AI and I am trying RL22 and IMR's 4350 and 4831. Some loads show promise and then go straight to hell. <img border="0" title="" alt="[Mad]" src="images/icons/mad.gif" /> It is killing me. I paid good money to have this rifle built and I hunted it once because I knew the shots would be under 100 yds. I really hate buying all these powders and bullets and having no luck. I am going to try Dan's method with the 280 and see if I can't do a better job. The 280AI is an Arg 09, L-Walther match bbl, the action and bolt have been faced, trued, whatever. The barrel and action machining were done by a very reputable gunsmith. I am hesitant to mention his name, primarily because I don't think at this point my reloading should have any reflection on his work. The parts are there, the load isn't. If nothing works I may send it out to have it checked up on eventually.

you forgot to mention barrel length and bullet type and weight?

quote:

Originally posted by dep:
you forgot to mention barrel length and bullet type and weight?

He forgot to mention it 5 and a half years ago .

Ken....

Have you ensured that neck tension and concentricity are consistent? Depending upon your style and type of shooting and your accuracy requirements, you might want to invest in the tools to read neck wall thickness and concentricity along with a lathe type neck turner/reamer if you don't have them now.

I found out the hard way that otherwise unexplained flyers can come from small variations in the neck.

Also, canted scopes and canted rifle hold will contribute to the production of odd grouping/flyers, especially when trying to hold off for windage.

If you are trying to develop a load in any wind at all it can be very frustrating. Sometime you could swear there is not enough wind to affect your POI, but using wind flags will show you how wrong you can be. They can be made very cheaply using dowels from the hardware store on top of which is pinned a length of surveyor's tape, also from the hardware store. I mount mine in the center of a chunk of 2x6 in which I have drilled a hole. My total cost per flag was about $4.50 adjusted for today's prices. Anyone trying to shoot and load for match accuracy really should be using wind flags.


These things I learned the hard way. I could have saved myself a lot of trouble had I subscribed to PS years ago. They also have a very good book listif you don't want to wait for articles about your specific concerns.
http://www.precisionshooting.com/

January, 2003, post.
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