Load Development... Ladder Day Revelations???

Pardon me, but I'm totally at a lost with this ladder methods. Even the concept of doing it at 300 yards because it's supposed to be better than at 100 yards. It is my understanding that if your load would not group at a 100, it certainly would not group at 300 yards either. On top of that, variables will increase exponentially from 100 to 300 yards and beyond. Conditions change from time to time. Proponement of this methods probably eliminated a lot of good loads just because it did not group will when they did their ladder test. Are environmental and physical conditions were taken into considerations when conducting this test?
Like I said in my previous comment, finding load that works is not that complicated, especially when developing loads for a custom rifle, chambered for inherently accurate cartridge, like for the 308, with tons of data available everywhere.

I found this load for my 308 in as little as 10 rounds.

This is a starting load of 44.3 grains of varget shooting 155 Scenar. Found this load researching the net.

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Next loading increased .5 grain to arrived at intended velocity resulted in this:

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Here's the same load performed at 200 yards. 5 shot group:

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No ladder test, nodes and all. I didn't even played with the seating depth.
 
Ref 8 ft rods for the Oehler. Answer is not one 8 ft rod, rather two 4 ft with one $1 electrical tubing connecter. All fits in your case.

The ladder is not for every rifle or shooter. this is an extreme accuracy method for extremely accurate shooters and guns. This is not for your 1 MOA grandpa's deer rifle.

If your gun or you are not capable of shooting .5 MOA then shoot 200 rounds to find a 1 MOA group. Or for that matter any other technique.

The reason you go to 300 or 400 yards in a no wind condition, is that an accurate gun with any load will stack all 10, 20 or 30 shots of a ladder easily under .75 at 100. It is physically impossible to track the bullet movement up the ladder (hint hint, that is why it is called a ladder). You must be able to see and track individual bullet impacts.

a ladder properly done will take your load data up through the upper end of the pressure curve for that gun and load. That is something that will not be found in reading one or four reloading manuals, because they will easily be 10% under max for most guns and custom actions will lose much more.

this technique does several things if you have an accurate gun and use some common sense.

Start with 20-30 rounds and go well into the upper range on powder. You want to hit the upper limit of pressure.

Load your bullets into the lands (or max seating depth for the mag OAL) IF you want max accuracy and do not worry about a magazine. Why is that? Well into the lands (or max OAL) gives you max pressure and when you move seating depths you only have one way to go an as you come out the pressure goes down.

You will need an accurate chrono, paper to plot your impacts and a zero target along with the ladder target (white posterboard works well) with black dot/cross for aiming. Plus 4-5 rounds at the lowest powder charge to zero on the other target. Good idea to be 1-2" high of aim point.

Put small dot on ladder target, and shot one round. Plot impact on sheet at bench. Write down MV beside each shot number.

Wait one minute repeat with round (charge two). repeat repeat until the last shot.

If you cannot accurately plot impacts on sheet, every 3-5 ( or if you have to each shot) rounds walk down to the target. look and mark on the target and your sheet.

have micrometer handy as you go up the ladder. Measure case expansion above the web and watch for pressure signs, ie highly flattened primers, sticky bolts, over .001 case expansion. If you get high pressure signs, then stop there.

Voila, you have just hit the upper limit of pressure and know exactly where it is. Normally the powder charge will will be higher (sometimes as much as 2-3 gr in med mags) than the manual.

Look at all your data and targets. Where does the MV stabilize for 3-4 shots? Those shots will probably coincide with where the same 3-4 bullets impacted closely together. That is node for that barrel, bullet, powder, primer and case combo. Change one component and it will not be the same. Basic reloading 101. You will find with a 20-30 shot ladder that you will have 2 maybe 3 good nodes.

Pick the node that is in the MV range you want. Do not pick the extreme upper or lower end of that range for that node for your powder. You want to have room for temp variations. Good time to mention I only use powders that are known not to be temp sensitive.

Go home and load 3-5 shot groups of that spread by .1gr increments with same seating depth and .010 off increments. Also same neck tension. You will have 3-4 groups at each .1gr and each .010.

VLDs tend to shoot better in the lands, so I always start in about .020. Regular bullets like Sierras tend to shoot better off, so I always start just touching.

Shoot these groups at 300/400 (no wind condition) over chrono. This will confirm original MV range, SD, ES etc along with grouping. This test will determine final powder charge and give you a .015 range for the seating depth.

Repeat test with .002 increments of seating and couple variations on neck tension if you have bushing dies.

You have fired 60-80 rds total and got your final load each and every time normally. You have 2 maybe 3 short range sessions.

Sometimes I repeat the ladder with another powder or bullet.

BH
 
It is no prob GG . A 8' pole fits diagonally in the bed of my pickup .

The fun was getting one made so that the dimples were aligned when you set up the skyscreens .

Jim B.
 
Bountyhunter ,

Weather must be bad so you cant shoot ....... or you are bored . Not sure which but you are giving the "time of day" to a lot of folks lately that in the past you would have let them go their " self deluded way .

I forgot another alternative , you're just getting soft in your old age /ubbthreads/images/graemlins/laugh.gif

Jim B.
 
I hate to sound really stupid but it seems that i have read so many different "ideas" as to how to conduct a ladder test. Can anyone supply me with a web site that may clear some of the confusion in my mind.
 
GHP

there are several links here on back to Creighton Audette who is a famous hightpower/NRA long range smith and shooter for highpower/NRA LR rifles.

he also wrote this about 15-20 years ago or more. The accuracy standard for HP then was much different and the use of chronos was not as widespread as today. Plus all these guns had match grade barrels on them. ie my insiststance that you have to have accurate guns and this is not for many factory guns.

You have to have faith that your bullet POI is indicitave of the accuracy of that gun. a 2-3" margin of POI error at 300 is not acceptable and will not show you anything as CS has pointed out.

In the last 10 years in 1k BR we have cut groups by almost 50% with the 5 shot record in IBS standing at 1.5" and 3.3 inches for 10 shots at 1000.

what I described above is my method and it was shown to me by several knowledgable (world class) shooters.

I have proven repeatedly with an accurate rifle this works and is repeatable. I have upgraded my reloading techniques and equipment such as all BR quality and Oehler 35 with 4 ft and 8 ft bars.

read, try and see what works for you, but doubt you are going to find a current definitive authority.

BH
 
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