Load development at 100 to 200 yards (hunting)

[Bginvestor]

I've read some good articles on ladder testing ; however, I want to load develop at a range that is only 100 to 200 yards.

Do you guys still attempt "ladder" testing? Seems various powder loads would group too tight..

Thanks for any suggestions..

 

[MudRunner2005]

I still ladder test my loads at 100 yards. The closest range to me is only a 100 max. So far, so good.

 

[LoneTraveler]

I am a firm believer, Take a chronograph with you to the range while developing loads. Shooting across a chrono. (buy or borrow) will tell you many things. Velocity, Average, low and High, Put a target at the bench and mark shot, number of shot, and velocity. Once you get an accurate load at 1 or 200 yds. then stretch it out. Some powders have to be run low or high velocity to get accuracy, It will tell to if the primers are performing well. Happy Shooting.

 

[FearNoWind]

I don't believe you can get meaningful results using Audette's "Ladder" testing techniques under 200 yards. I'd prefer a minimum of 300 yards; more where possible. It's a certainty that you will see variations in group prints on target at 100 yards but "Ladder" results are not, IMO, meaningfully represented in that data.

 

[bill123]

Try this: OCW Overview - Dan Newberry's OCW Load Development System

 

[FearNoWind]

Try this: OCW Overview - Dan Newberry's OCW Load Development System

I've never understood what "2%" meant in the OCW test.
Is it 2% of the initial charge weight (e.g. 2% of 52 grains is 1.04 grains - do we repeat that by increasing each load sequence by 1.04 grains) or is it 2% of each charge weight increase (e.g. 2% of 52 grains = 53.04 grains, 2% of 53.04 grains =54.1 grains) etc. Is the formula linear or exponential?

 

[pods8]

Right/wrong here's what I've done when dealing with 100yd ranges to do most initial work at:

Load up .5gr incremental singles and shoot them over a chrono while comparing velocity/bolt lift/primers and reviewing against any published data for that combo to get an idea of what a max charge may be for the components I have in hand.

Then depening on case capacity I'll load up incremental singles in .1gr or .2gr steps so I cover the upper portion of the charge range (but below the max). I'll put up a few targets that all have 3 aim points per sheet, and I'll shoot 3 shots per aimpoint (that's a good amount that I can keep track of each individual hit). I'll log the velocity and location.

Then at home I'll compare the hits/velocity of things (superimpose them between aimpoints as needed) and look for the adjoining powder charges that gave the tightest combinations. Assuming a few in there I'll load up 3 or 5 shot groups of those and try those out. Ideally something shows promise from that and then you evaluate at longer distances and try to tweak seating depth, etc.

That's worked for me in the sub 400yd stuff.

 

[bill123]

I've never understood what "2%" meant in the OCW test.
Is it 2% of the initial charge weight (e.g. 2% of 52 grains is 1.04 grains - do we repeat that by increasing each load sequence by 1.04 grains) or is it 2% of each charge weight increase (e.g. 2% of 52 grains = 53.04 grains, 2% of 53.04 grains =54.1 grains) etc. Is the formula linear or exponential?

2% increasing by the same increment from lowest charge until you get to the point where you increase by only .7-1%.

OCW Overview - Dan Newberry's OCW Load Development System

 

[Bginvestor]

Thanks for the feedback guys! I like the OCW article..

 

[bill123]

Thanks for the feedback guys! I like the OCW article..

BTW its not just for short range load dev. I Used OCW on my .308 load and it gave me outstanding results at 1000 yards.

 

[Bginvestor]

I'm starting from scratch on a couple of rifles.. I have selected three bullets before down selecting to the ocw method . Any suggestions on c.o.l and number of minimal rounds to accomplish this ..

 

[bill123]

I'm starting from scratch on a couple of rifles.. I have selected three bullets before down selecting to the ocw method . Any suggestions on c.o.l and number of minimal rounds to accomplish this ..

From Dan's website regarding seating depth: OCW Overview - Dan Newberry's OCW Load Development System

6. The seating depth for all test loads should of course be the same. I normally seat the bullet a caliber's depth into the case, or to magazine length--whichever is shorter. I don't believe loading to approach the lands is necessary, or even desirable in most situations. So long as the bullets are seated straight, with as little runout as possible, the advantages of loading close to the lands are largely over-stated. This said, be certain that the seating depth you choose does not cram the bullet into the lands. Stay at least .020" or so off the lands for these exercises.

An example of his procedure: OCW Overview - Dan Newberry's OCW Load Development System