Okay, first time reloading .223.

My testing protocol has been limited to 1911s. I'm not up to speed on testing for rifle, and my emphasis in the past has been forty feet, which is the very longest shot possible inside my house. (I measured.) I have a dozen loads that will shoot well out of any of my 1911s at forty feet, but when you make it a .223 bolt gun, and increase the range to a hundred yards, not so much.

So I've been rattling around the net, reading stuff, and the most logical procedure I've read was called a "ladder test". My new rifle is a Ruger Hawkeye. (A bolt gun. A heavy bolt gun. A really fucking heavy bolt gun. If I ever decide to wander around the woods with a rifle, I either need a different rifle or a cute woman to carry it for me. I'm willing to carry it to the firing line at a range and back. No further.) I have a scope for it from SWFA. I'm still getting used to a scope. I've never used anything but iron sights on rifles. But the calendar has decreed that a target at 200 yards will no longer be clear to me over iron sights. Hang in there. I'm told it happens to everyone. If you're lucky, it will happen to you, too.

The first step is pressure testing, and establishing a maximum load for my rifle. Start with half a dozen rounds at the lowest load, to sight in and foul/warm the barrel. Then one round at increasing loads, stop when pressure signs show up. I intend to use a chronograph (a new LabRadar) and measure the diameter of the case head, that served me well with .45 brass.

The next step is three rounds from each step, at three different targets, one round from each step, looking for a vertical group that indicates a node of power that the rifle likes.

I've taken the load straight out of the Hornady manual, with no changes. As per the manual, new Winchester brass, Winchester small rifle primers. Hornady 52 grain A-MAX bullets. The powder is Hogdon BL-C(2). This is the note I have in my "Notes" field in my database:

6/16/16-- Designed straight out of the Hornady load manual as the first load for the Ruger Hawkeye. Cartridge length is the max length in the book, I intend to adjust it to the Hawkeye. This load will be tested in 0.2 grain increments up to the max load in the Hornady manual, starting at 22.5 up to 27.4.

That generates 26 loads! I hope that drops down to a reasonable number after the first trip to the range! I'm thinking of doing one load every .3, or even one load every .5 grains, at least until I get a maximum load established.

For you experienced .223 loaders, does this sound like a reasonable procedure? Do I understand ladder testing correctly?

I did ladder testing on one .223, you really need a range longer than 200yd to do it but you have the general idea. I used several colors of permanent marker on the bullets to keep from mixing up adjacent shots. Hopefully the rifle shoots well or it will be frustrating at best.

Yes, you understand the ladder correctly.

I did every .3 grs, and like srey, used colored permanent markers to keep them in order.
Naturally your ladder test will only be valid/applicable to that powder type/bullet type/primer type.
As soon as you change one of those components, you'll need another ladder test.

That sounds like the ladder test.

With a flat shooting round you have to get way out there unless you take big steps (.5 gr qualifies as a big step for heavier rounds, not sure about .223. Might be a huge step.)
What you are looking for is a steady progression of the POI moving up to the bullseye as your charge goes up, and the ideal load to concentrate on is where 3 or 4 sequential changes in powder charge don't make a significant movement of the POI.
That's the sweet spot.

Just understand that sometimes 0.1 - 0.2 grains can make a difference in accuracy.

First, charge weight changes should be limited to 1% max per increment. For a .223 round that would be .2-.3 gr. For a 30-06, more like .5-.6 gr.

Rather than using the old Creighton Audette "Ladder Test", try the Dan Newberry OCW. You can end up using a lot of ammo with a ladder test where the OCW test takes 15 rounds for it's first run through.

http://optimalchargeweight.embarqspace.com/#

Follow the instructions TO THE LETTER and you'll be less frustrated than with the Ladder Test. Unless you have a really long range, a good spotting scope, or a target camera, the Ladder test will often leave you with more questions than answers at the end.

Not exactly. The purpose of the Audette Ladder Test is to identify charge weights where the POI's are similar. This identifies the harmonic nodes in the rifle barrel.

As you change charge weights the barrel can oscillate in such a manner that the POI actually goes DOWN as the charge is increased and then go back up. It all depends on where the muzzle of the barrel is pointing when the bullet leaves. What you describe is true if a barrel was totally rigid, but we know that's not the case.

With an Audette Ladder Test you merely use the "nodes" to work up your final load and don't have to fart around shooting 3-5 round groups for ever few tenths of charge weight intervals. Most rifles will have two distinct nodes, one fast and one slower. Some have three with the third usually being at or slightly above the published max load.

Interestin!

I appreciate the education sir! I picked up the little that I know from a friend a few decades ago. Have used my simplistic version since then.
Looks like I have some more learning to do.

Actually I think I did that when I found the sweet spot for my .280 round last week. lol.

I picked the charge that A) didn't have a significant up or down elevation and B) grouped nice and tight.
I used 3 rds each, .6 grain difference, and 5 loads. (18 rds total)

A little more on the Audette Ladder Test, the guy who created it used 300 yard targets. Many today will use targets out twice that distance as the longer the range, the more meaningful the "data".

Since most ranges around the country have limited distances the OCW method is more "attractive" as it can yield very good results at 100 yards (although I prefer 200 yards myself).

Skip the the ladder and OCW and go right to OBT. Optimum Barrel Time requires a chrono and QuickLoad but it works. I use to test via OCW but now I go to OBT and then if I feel like it I do a OCW with the 2 or 3 loads around the OBT node.

http://www.the-long-family.com/OBT_paper.htm

Well, shit. There went an hour.

Good stuff.

Excellent link. I love the science behind this stuff.

Edit: Sooooooooo, do you have the QuickLOAD software?

+1 for OBT. We use a similar method combined with our best practices for external and terminal ballistics in the software we've developed for fast and precise load development.

Without going the software/simulation route, a ladder test is a great way to corroborate your OCW tests. There is more to a stable load than just the height that the bullet hits the paper, which is why these two approaches together are pretty robust. Make sure you take good notes and record the time between shots, as well as have consistent sand bag pressure if shooting from the bench. Basically, anything that can induce vertical stringing can render a ladder test extremely frustrating, so close all of those gaps when at the range.

Cheers!
Michael
Vantage Reloading