Help with translating a ladder test

powdergun

powdergun

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So finally starting to get to know my new toy and shot a ladder test.

Temp 32 degrees ( frikken hot)
Wind about 10-15 mph at about 90 degrees
Cartridge 300WM
185 Berger loaded to lands
IMR 4831 66.1 gr to 69.0 gr loaded in .3 gr increments

Range 300 yards

( Shots 2 and 8 are my fault. I knew I was not on)

Am I correct in calling the node at shots 3, 4, and 5 ? ( 3 and 5 are only .78" apart vertically and 4 and 5 are pretty much exactly on the same line ) or would you try 9 and 10 ( Wish I hadn't pooched those two shots)


jcw3ps7.jpg


BTW coloured each bullet with a sharpie and boy does that work well.
 
Sure wish I hadn't flubbed 8. Would of liked to see if it was close to 9 and 10.

It has been a challenge trying to find a day when the wind wasn't crazy out there on the west range. lol... I think I will take your advice and try shooting groups at 200 with 9 and 10, 6 and 7, and 4 and 5 just to see. Zero pressure issues so I hope the 9-10 load will work out as I get more speed.

Got to say this rifle seems to shoot anything well and its potential far exceeds my abilities lol...
 
It does look like a combo the rifle doesn't mind at all.

I've been fighting with one particular rifle all summer, well you've seen my tests. Atrocious .

I'm glad you are having better luck.

No velocities at this point?
 
I need to get a chrony and I know I am at a point where I need that info. Books say I am about 2800-3000 but you know how valid that is.
 
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From what I have looked into a ladder test can at least narrow down which loads to test. Shooting groups of every possible load and powder can go through a lot of components plus raises the shot count on the barrel. Hopefully I now have two or three loads I can confidently test rather than all ten.

I know the debate will rage on forever as to which method works best but that is all part of the fun I guess. Who knows I may have to shoot a pile of groups before I finally get to where I want.
 
powdergun said:
From what I have looked into a ladder test can at least narrow down which loads to test. Shooting groups of every possible load and powder can go through a lot of components plus raises the shot count on the barrel. Hopefully I now have two or three loads I can confidently test rather than all ten.

I know the debate will rage on forever as to which method works best but that is all part of the fun I guess. Who knows I may have to shoot a pile of groups before I finally get to where I want.
Click to expand...

Buy a chronograph! They’re worth every penny!

I used to do ladder tests on paper at 500 yards before I had a chrony, of course I would always have doubts about whether a shot was flubbed or accurate. When doing ladder tests with a chrony you remove all doubt about your shooting abilities, the velocities don’t lie, and the nodes are easy to find.
 
Not cheap. I was thinking on a lower end Caldwell or chrony product if they are any good.

Unsure about magnetospeed as strapping something on to the barrel would most likely affect POI so you could not load test and measure velocities at the same time. ( If I am wrong please say so )
 
powdergun said:
Not cheap. I was thinking on a lower end Caldwell or chrony product if they are any good.

Unsure about magnetospeed as strapping something on to the barrel would most likely affect POI so you could not load test and measure velocities at the same time. ( If I am wrong please say so )
Click to expand...

I am thinking the same, we work so hard to tune our rifles and then we strap a device to the end to test it.

My chrony works , but I think is temperamental.

I like the idea though of not having to line the damn thing up perfectly each time.

As well. Chrony appears to be belly up or out of business.
 
A chronograph is handy to have but it is FAR from definitive as to which loading makes for an accurate group. Just because you get an ES of less than 10 and an SD in the low single digits means absolutely nothing. Just because you get a 'node' at 44.15grs +/- 0.2grs also means absolutely nothing. The holes in the paper are definitive and the chrony data may allow some fine tuning. I have a stack of paper with holes in it about 6 inches high. All my testing over the past 6 plus years. Stapled to each is a page detailing all the pertinent data including chrony results. It is amazing how many of those incredibly good groups of holes have some of the worst ES and SD numbers. Most don't give quite the same accuracy at 100 or 500m but they are pretty close and repeatable at the distance I shot them (usually 300m but could be 500m for some). Anyway, nodes are handy to find if you are distance shooting and want to be able to have a fairly reliable load at 100 and at 1200m, but if you are shooting at some arbitrary distance +/- 100m consistently then finding the most accurate loading possible at that range is preferable. My opinion and for what I do it works.

As to Labradar and Magnetospeed, plus and minus to each. POI can change at times with the Magnetospeed but the accuracy doesn't. In other words, if the rifle is shooting 1/2MOA groups without it, it will still shoot 1/2MOA groups with it. POI may shift slightly but the group size won't change appreciably. The thing I like about the Magnetospeed is that it is ALWAYS ON and reading data once it is put on and connected. As to the Labradar, once I get it perfectly aligned it will give me readings out to 80m. I can get some rudimentary BCs from the data. I don't like the fact that it times out, or I forget to 'ARM' it, and it has a terrible bluetooth interface with my iPhone or iPad which seems to disconnect at whim.
 
As to the cost of a Mag or a Lab, once you factor in the cost of your ammo, they tend to be fairly cheap. Every time I go to the range I blow through a couple of hundred dollars worth of reloaded ammo, never mind the cost of getting there and back. If you are going through all this effort just to sight in your hunting rifle, forget it. Three shots, adjust your sights. Wait half an hour, three shots to confirm and you are done. You want to be dead on with a cold barrel for hunting.
 
Ive always had better luck firing 3 shot groups of each charge weight at a given range and work off the best group refining charge weight and seating depth. More than not the best group was outside of what looked promising on a latter test. 3 shots gives a more predictable outcome than a single round
I use my chrony to help identify any over pressures and to get an idea of drop so i can make a chart to compare my shooting to
 
to be honest, with my huntin rifle, same as brybenn.... with the lever action and ruger #1, i only really test 3 shots but as long as 1 and 2 are within the spot im aiming- those rifles are good to go hunting. horses for courses , they shoot under 200m.

with my bolts, i shoot under 400 majority of the time too, 200m would be the average- so the 3 shots closest to an inch they can be is my load.

i wondered about the ladder tests myself, but from doing some researching, you can often get a gist of the rifle, calibre and cartridge in question, alot of published data for the powder manufacturers means theres already a 5gr margin to start with, history has shown alot of guns like a 'lower' charge and the same ones might get similiar accuracy in the 'high' range but the average hunter is happy with less 'bang' forthe same buck, less powder over all, longer brass life, maybe throat life min V maxed , an most will shoot under 200m with 400m being out there.?

i understand some guys hobbies are to chase tiniest hole the gun can make or it isnt interesting, but thats a different kettle of fish for a hunting rifle V an accurate rifle. imo.

:) hooroo
 
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