Home Forums Hunting & Shooting Long Range Hunting Ladder test, How, why?

That was a great post! Thanks for the explanation!

John

+1

That took time, thought, and patience.

SD numbers that most people quote are based on a statistically invalid number of sample shots anyway, so unless you're shooting 50 rounds over the chrono to get a SD value, it's easy for a guy to think he's shooting the load with the lowest SD, but if he ran a few more shots over the chrono he may be surprised when the SD goes up.

You are talking 172 FMJ when you say 172s. When I say 175s I'm saying 175 sierra BTHP match. THey are NOT made at LC< but at Sierra. And they are a proven match bullet, where the 172 was an improvement on the ball 150s... they never have been a true match bullet. Heck the more it think, maybe the ball in special ball was actually 173?

First thing you do when issued the special ball is try to have a seater so you can crack the tar seal on the bullets... and then shoot em. Helps a bit with accuracy.

The M118LR is a fairly new iteration, using only the 175 sierra as far as I know.

Oehler 35 non P.

I have found some test runs with 10 shot groups when you are not looking in the scope, but shooting a group but watching the chrono, this should be the best ever group... but while its totally ok, its not been oustanding.

Mind you my personal take is that you trust paper to 600, and don't pay that much attention to SD and ES, but beyond that we hit paper next at 800 and there you have to pay attention to paper too, but the vertical there and beyond will more visibly tie to the variation of the MV of each shot.

Its not that I don't look for ES and SD. But I base my choice of a given load for what it does on the target, not the chrono.

If that makes more sense.

None of my good loads have high ES or SD. Not a one of them is the very best ES/SD I've ever shot in 10 shot groups. No clue why.

Wouldn't that all depend on the original lot of ammunition loaded?
Most don't load 1000's of rounds at a time.
So, out of a batch of say 200, what would an appropriate sample be?
I am thinking less than 50...

R.

In Nov-Dec 99 was the last time I fired 118SB (172gr) in bulk quantities (MTT at Carson). I fired 118LR in late 2003 at SOTIC.

Yes I should of been clearer and said 175 SMK.

But ya gotta know that folks quote an ES /SD from a single 5 or 10 shot group as a best case scenario a lot of times.

Folks have to understand that a small average, ain't much of an average statistically.

I wouldn't care if over a 1000 rounds, the ES was off, RE day to day variations, as long as the overall spread from day to day was on the low side.

From the math side it would be interesting to know what a math guy thinks of numbers.

And to be clear here, no one is taking away from your mentioned caribou kills. Very nice work. And good eats to, assuming not in the rut.
Just that you have to compare apples to apples in a lot of these instances.

What it takes for one thing, isn't the same needs for another.

Heck... when I was a kid, you know as a stupid azz slow window licking leaner..... it took me some time to become proficient at what I thought was a long way.. 200 ish yards across a field.....

Later down the line, some days 200 yards can still be tough, even in a sling kneeling or sitting when the wind blows you so much you can't stay in the kill zone.... and other days given the right conditions, 500-600-700 isn't anything but a chip shot.

My methodology is pretty similar after I have done basic research to determine, bullet,primer, and powder combo I want to use/test for each ladder.

1. Shoot ONLY in early morning or evening in no wind conditions.

2. minimum of 300 yards prefer 400. I have found that seems to be the ideal distance for enough vertical dispersion as the bullets walk up and close enough to see bullet impacts with good spotting scope on white target.

3. 35P chrono

4. Minature paper target at bench to plot each round and another sheet to write down each MV for each round. That way I do not lose track of any bullet shot as each is numbered on plot sheet and anytime I go down range to verify impact.

5. Minimum of 1 minute between shots from starting dirty bore, I usually zero at that distance on another target at the side to confirm accurate zeroa for bottom of ladder target which is normally large plain white cardboard with 1" aiming dot near bottom. I use .3 grain for large cases and .2 for smaller cases as increments.

6. If I am not 100% sure of bullet location, I either walk down or use colored magic markers on bullet tips which show up on target. No they will not vary impact points on target. That is used all the time at 1K BR to identify any crossfires on your target.

7. MV as you go up will be linear until you hit a node and then it tends to decrease dramatically for that 2-4 shots and then jump linear again. You will see 3 rds with small MV variances normally in the node and then jump dramatically again.

Combination of bullet AND MV grouping confirms node and is usually easy to see when you compare the two!!

8. I pick a middle node, shoot groups to confirm basic accuracy and ES, SD nodes. I normally find 2 mabye three nodes, and one will be in the MV range I am looking for. Many times the top one is at the starting of high pressure point, so often do not use that one. Middle of the node gives me enough variance on temps and other factors that I am not out of the node on any given day.

9. Try groups at various seating depths at my best grouping and see what depth it likes. single shot gun start, .010 in and come out. Magazine gun, start at max magazine COAL and in from there.

10. If the gun will not shoot 1 MOA, that makes shooting a ladder a little difficult as you do not know what is the real vertical or 3-4MOA grouping "inability", so IMO it is not for every gun.

I didn't know anyone else did the colored magic marker thing...

I've tried to use white paint pens on them, hoping it would make spotting easy in one of our rapid fire matches that starts with no verification zeros in full wind and at 600 yards, the advantage there was not nearly enough. Ended up chasing thermal imaging but never got far enough before we quit shooting competitively... but I digress.

Good point aobut fouled bore and time between shots. I take it for granted on some things.

And ESPECIALLY if you have changed powders.... I won't shoot any test without at LEAST 5 of a different powder down the tubes. 1-2 usually is enough.... but....

Charge increments, IIRC was suggested 1% of case capacity? as an increment?

On mags I don't do anything smaller than .5 to start with.

Only other thing on COAL with a mag fed round, I want to know where the bullet touches so that I have an idea of how much jump I am dealing with... and so that I know i'm not jammed....which could happen with certain setups.

We're having a good discussion now. I've been an advocate of the ladder method for almost 20 years and never had disappointing results. That said, I mainly use it on my LR/Palma/XTC competition rifles and my varmint rifles where precise accuracy is most important. Doesn't make sense for a lever action .35 Rem that will only be used inside 200 yards. For my deer rifles (.280/30-06 class) I will usually pick the bullet and powder I want to use, seat .030 off the lands, load five in increments of .5 grain starting 2gr below max and shoot groups and measure velocity at 200yds. I'm looking for sub-moa and respectable velocity and when I find it I load more and confirm that recipe. It's difficult for me to find a place to shoot past 200 to yield best results from the ladder, so this modified ladder works pretty well for me and I usually quickly find a hunting accuracy load. Twice, it hasn't worked as well and I did the full ladder work up, plus varying seating depth and found 3/4 MOA loads. On all my competition rifles I verify the node with two or three ten shot groups shot at the pace I would in a match, which is usually as quickly as the wind will allow. Hunting rifles use 3-5 shot groups fired in a minute or two, as I would in the field if I missed :-(

The confidence I've been able to build into my loads helped me quickly get to Master class in LR and XTC as well as win the Wisconsin State LR title for my class a few years back. Unfortunately, my shooting activity has been sidelined a bit due to family duties with kids getting older, but they are getting close to the age of being able to start themselves, so it will pickup.

Certain posters aren't here.


What a coincidence

Congrats on the good use of the ladder. And moving up the class ladder!

Audette helped me the same. Made it in service rifle to HM in XC and service rifle HM in LR also. Though they included 600 yard scores which are not really in there IMHO.

I'd like to see another thread about seating depth, which for service rifle, I've not had to chase, but I have a hunting rifle thats driven me somewhat nuts at times... would love to see how folks run a seating depth ladder so to speak.

Good luck with the kids!

Jeff

I take the load that shot best from the node and do the test at 100 yards.


My procedure is the same as shooting the ladder in the first place, ie. I go to the range with my prepped, charged cases (with the chosen charge), bullets, press, calipers, comparator.

Since I had run the Audette with the OAL either magazine length or just off of the lands, I only need to seat the bullet deeper a certain, predetermined amount. Many times the seating depth used to find the load will do just fine. Others need to be adjusted.

At the matches I shoot, there is a lot of 100 yard shooting for score on paper. We routinely have stages where a 1/4" dot will garner the most points. It's important to have not only a Long Range load that has minimal vertical, but also have that load tuned as well as possible at 100 yards

At the range, I seat bullets into two of the cases at my longest chosen OAL and shoot them at my 100 yard target. If the two holes are looking like a third may make a good group, I'll seat another and shoot it. If the two holes are so far apart that it's obvious the depth is wrong and the group will be unacceptable, I move on to the next chosen depth. I usually seat .010 to .015" deeper in the case for each new depth.

When I find a depth that piles them into some kind of a 1/2" group or better, I'm done.

I have tried the seating test recommended on the Berger Bullet site. Shoot groups at the lands, .040" off, .080" off, and .120" off. One will shoot better than the rest. Then I work in and out from that depth in the same manner. It will work with other bullets as well other than the VLD.

At this point I have found the best load and the best depth.

I also have many more cases charged and ready for seating while I'm at the range. I seat bullets in all of the cases and move on to the silhouette range to nail down the drops as far out as I can shoot at steel. We have two ranges. One goes to 1000 with steel and the other 760.

Usually if I have enough cases charged at the beginning of the day for the Audette(100), I can knock all of this out in the same trip. I usually bring my scale to make more of the load chosen from the node if necessary to do some shooting at steel.

It does definitely depend on the number of rounds in the population, meaning that if you plan on re-developing your load and re-testing for SD/ES for every batch of 200 rounds of ammo you load, then yes the calcs would be based on a population of 200. But if you develop a load and then produce 1000 rounds of it in batches of 200, then you're working with a population of 1000, not 200.

When you calculate the required sample size to have a 95% confidence interval and a sub-10 SD, it's a lot larger than most people think. Suffice it to say that a sample of 10 or even 20 shots is fairly meaningless when it comes to getting an accurate SD number.

Probably at home looking in the mirror admiring his big head!

Saying "Look at me look at me!"

I use the smaller increments (.2 or .3 gr) as I am looking for that 3-5 shot grouping and smaller increments make it more readily apparent. Other load development I will use larger increments and tune from there.

too easy to miss the node or middle which is what I want to find.

How many play with 0.1 grain powder increments for group shooting once you are in the middle of the node? I know I have at times.. just to be fairly certain I'm actually as far in the middle as I can be.... IE as close to having most leeway boht directions.


Interesting on seating depth, what I was mostly wondering, whats enough to be noticeable when testing? IE .010 or .040? If you fall in a node that says both .040 and .080 are about the same, how small of increments will you try to center up in the middle or will you split and call good?

I know that most of us have a certain desire of accuracy, and once we hit that, we tend to call it good and move forward. Barrels dont' live forever and ammo and time ain't cheap...

Does anyone actually simply shoot same as the original audette RE COAL, certain movement and only one shot each to see if if htere is a wide spot there of happiness?

I hear ya on 2 shots and no more if they don't meet muster... always hated having loaded 5 shot test groups and the first two at 100 were 2 inches apart...

Got to the point that I started loading 2 each and shooting just to see... but decided 3 was more non flukish.... and then came across Creightons article reprint.

I"m lucky though, I have 600 yards sitting out the door. Good benches at 100,200,300 and portable one at the rest.... steel on skids. Which sits at 600 most of its life.