Question about load development.

[marioq]

So here is my question. I'm trying to shoot tight groups and develope a load. What yardage should I do this? Is 25 yards good to just look for grouping? 50? 100??
I know I won't test it at short yardage but just to see how they group based on grains of powder.
Thanks for yalls input!!

Mario

 

[4xforfun]

I do some prelims at 100. But, that is usually just one 3shot group at each powder weight up to find max.

Then, it's off to 300 for a few more tests.

I usually shoot 600 or more when I am doing my final tweaking...neck tention, seating depths, maybe bump the powder a tenth or two. This is where you will catch the vertical in your groups.

 

[kcebcj]

It's been my experience mainly with 30 cal bullets that you can work with flat based bullets at a 100 yards and have them stay fairly accurate on out. With boat tails bullets I will shoot a group of 5 at 100 yards once the rifle is sighted then move out to my 335 yard target to finish the work. I usually see a measured impact difference between 100 and 335 yards with the boat tails but not much with the flat based bullets.

There is a point where the bullet settles down (goes to sleep) and when working up a load you have to be beyond that point to read what's going on accurately. No load workup should be done at less than 100 yards but I don't know that for sure with a flat based bullet. Boat tails need to be beyond 200 yards in my opinion for final tuning.

Run a search in the forum and learn how to perform a ladder test used for finding a sweet spot for a particular powder with a particular bullet.

 

[Sully2]

So here is my question. I'm trying to shoot tight groups and develope a load. What yardage should I do this? Is 25 yards good to just look for grouping? 50? 100??
I know I won't test it at short yardage but just to see how they group based on grains of powder.
Thanks for yalls input!!

Mario

25 is EXtremely close...and the smallest fraction of an inch "grouping wise" will mean a BUNCH out at range.

I start at 50 yards just to get it "right" on paper...then move to 100 to start checking groups. Since Ive run the ballistics calc on Hornadys website, I know that at 50 yds I need to be dead center "right . left" and be close to "X" high ( based on my 200 or so yard zero) I get it right at that distance

Moving to 100 yards I stlll have to be "right on" "right and left" at thusly the bullet should have...SHOULD HAVE...risen to "X+" height. If it hasnt...I tweak it there ( at 100 yards)

It should be "good enough" per the ballistics charts for any additional distance BUT...if its some like a PD rifle...I got to move back to the 200 or further line.

Lots of differences in accuracy between a prairie dog rifle and a mule deer rifle.....that is unless PD's have grown some...???

I mainly shoot 3 shot groups

 

[marioq]

That's Helpful!!! Thanks you guys for your input... I won't go to Baasspro indoor range today.... I will wait till it calms down with the wind and I can shoot at 100 yards...
Then back out to 200 and beyond!!!!

Thanks

 

[Greyfox]

Unless you shooting a bullet that is known for questionable stability at shorter ranges I'd do the bulk of your load development at 100 yards, especially if wind is present. For group testing you want to eliminate as many extraneous variables as you can, wind being the greatest. You will easily see differences due to bullet, powder charge, etc. Let the barrel cool between 3 or 5 shot groups. When you find your best group, then do your work at the longer ranges. It is rare that you will have a substantial difference in basic accuracy between 100 and 300 yards unless you have a major mismatch between bullet and twist, or are using heavy for caliber VLD design.

 

[grit]

Shooting 100 yards WITH a chonograph will give you the info you need in most cases. If you are shooting VLD's they sometimes don't finally stabilize until after 100 yards. In this case 200 yards will provide better feed back. Always verify what the groups and chrono tell you at long range.

 

[Nimrod]

I personally sight in at 25 yards to get on the bull, usually takes a shot or 2, then move over to the 200 yard target, set up the chronograph and do the bulk of my load development there. To shoot my drop tables I use steel plates. For practice I shoot at random targets in the field.

Bob