Need advice on ladder load development

[Papa Charlie]

I am trying to determine what bullet and what load for my .308. I have been shooting F-Class at 500 yards with Berger 185gr Juggernauts and have been very happy with the results. But I would like to try my hand at F-Class at 1000 yards. So I purchased some Berger 200.20X and some Berger 215gr Hybrids.
Got a chance to go out today and do a ladder test with both. Powder is Varget, seated rounds for 0.010" jump OTLs. I fired 5 rounds at each load which varied by 0.5grs between loads. I only have a 200 yard range available but would have preferred 300-500 yards.
While it is easy for me to see some loads just won't work, I am having trouble identifying which load is the best for both the 200 and 215 grain bullets.

So which loads do you think show the best possibilities.

 

[ImBIllT]

5 and 9 on both bullets. It’s slightly more clear on the 215s. If you’ll notice 1-3 impact the same place, then the impact rises. You don’t want to be on the cusp of this shift so 4 is out regardless of what the group looks like. Then on the 215s 6 and 7 show slightly more vertical. It’s hard to say with certainty that it’s not random, but it comes after the shift and some tighter groups. 8 and 10 seem to show two distinct POIs a high and low. The center of the groups are the same as 5 and 9, but there are no bullets in the center. This can mean that your load is right in the cusp of the POI shift. A load a few tenths under might print low and a few tenths over night print high and the load tested jumps back and forth. Statistically you’d have to shoot a lot more to know for sure, sometimes when you see a good thing, there’s no reason to keep tearing the questionable thing. Shoot 5 and 9 again and if one or both of them give decent groups again then just pick one and rock it.

I guess it’s actually 6 on the 200s. You know which group I mean. It also exhibits a little of the high/low no center thing, so another group to check it would be worth doing. If it does that again you might lean more toward nine.

 

[group therapy]

are ladders supposed to be 5 shot or 3 shot? I thought 3, but not sure

 

[IdahoSharpshooter]

You might have stayed with the Juggernauts and gone happy, imho. Palma guys are often under moa with the 155 Palma bullet at that distance.

 

[Clancy]

A ladder test shot at any distance less than what you intend to shoot has always seemed unreasonable to me. At 200 yards, it won’t reveal anything earth shattering.

After trying about every load development method known to man, I have settled firmly on Erik Cortina’s “long range load development at 100 yards.” It absolutely will not lie to you, and I recommend a quick seating depth test with a warm charge prior to doing the test, becuase smaller groups are easier to read.

If forced to pick from your above targets, I’d say “9.5” on both counts.

 

[Papa Charlie]

Thanks all for the input. I agree, if I had a longer distance to test at, I would have, but I am making due with what is available.
I can see what you are talking about now that you pointed it out. So I will play with 6 and 9 on the 200gr and 5 and 9 on the 215gr. Probably due three workups at each, one with the same load and one 0.2gr above and 0.2gr below.
Once I get down to a single load for both, I will play with seating adjusting the jump.
As for the Juggernauts, I don't know how they will work at 1000 yards. I will probably try them also at that range.

 

[Ned Ludd]

What you are showing is an Optimal Charge Weight test (OCW), not a ladder. The idea is to look for at least two, preferably three increasing charge weights in a row where the centerpoint of the group doesn't change. In the images you showed above, it looks like #2 and #9 for the 200s. In other words, the centerpoints of groups #1, #2, and #3, and #8, #9, #10 aren't changing position on the target much. The idea is to select the middle of the "window", then go back and test around it in smaller charge weight increments. So you could go back and re-test around #2 and #9 with the 200s using +/- a couple 0.2 gr charge weight increments. On the 215 target, it looks like #2, #5, and #9 are in the middle of charge weight regions where the groups don't move around very much on the target.

The other thing you can do if you have a chronograph is to take advantage of the information available from many other shooters already using these bullets. Typical F-TR loads from a 30" barrel with the 200.20X bullet and Varget will fall in somewhere the 2640-2670 fps range. There is a higher node at around 2700-2720 fps, but it will be much harder on the brass and will also have more recoil. Likewise with the 215s, 2540 to 2570 fps is where others' reported loads seem to generally end up with Varget or H4350 and a 30" barrel. In your case, you seem to have both high and low windows on your OCW targets shown above. It shouldn't be too difficult to determine using a chronograph which correspond to these well-known velocity windows. In other words, if your charge weight #2 regions are considerably slower than that, OR the #9 regions are quite a bit faster, it can help you decide which region to focus on further.

 

[Papa Charlie]

Thanks Ned. Appreciate the input.
I didn't use the chronograph because I have the Magnetospeed and it throws my rounds off. Want a LaRadar but I am saving my shooting equipment budget for a Joypod I have on order. Next will be the Labradar.

 

[Clancy]

Jumping .5 grains is a lot, which is why I suggested “9.5”

 

[Papa Charlie]

Jumping .5 grains is a lot, which is why I suggested “9.5”

Not sure what you are referring to. The numbers represent load numbers not the amount of powder.
My loads are as follows:
200gr, 37.5 to 42 grains in 0.5gr increments.
315gr, 36.5 to 41 grains in 0.5gr increments.

 

[BP1]

Pat what’s the freebore on your barrel?

 

[Papa Charlie]

Pat what’s the freebore on your barrel?

Right now it is 0.126", it has grown 0.016" in 935 rounds.

 

[Pwc]

Try here:
https://www.thehighroad.org/index.p...-waste-of-time-for-long-range-loading.839630/

or here:
http://www.gunsandtactics.com/performing-the-ladder-test

personally I like the first one.

 

[Clancy]

Not sure what you are referring to. The numbers represent load numbers not the amount of powder.
My loads are as follows:
200gr, 37.5 to 42 grains in 0.5gr increments.
315gr, 36.5 to 41 grains in 0.5gr increments.

I understand, and what I am saying is that you can load between your 9 and 10 charges as there is a full half a grain difference and you are using a temp stable powder. This is assuming you did not see any pressure.

You can easily come in and out of a narrow node with half a grain, but squarely between your 9 and 10 charges is where you want to be.

 

[Bc'z]

Not sure what you are referring to. The numbers represent load numbers not the amount of powder.
My loads are as follows:
200gr, 37.5 to 42 grains in 0.5gr increments.
315gr, 36.5 to 41 grains in 0.5gr increments.

I also load in what's referred to as OCW.
I also use to load them in .5 increments, I've switched to .3 increments as I'm finding it easier to see the sweet spot and dont have to do as much testing above or below.
Also seeing lower and higher nodes more easily.

 

[Papa Charlie]

I understand, and what I am saying is that you can load between your 9 and 10 charges as there is a full half a grain difference and you are using a temp stable powder. This is assuming you did not see any pressure.

You can easily come in and out of a narrow node with half a grain, but squarely between your 9 and 10 charges is where you want to be.

Ok thanks for the explanation.

 

[jsthntn247]

6 and 9 with the 200's and 8-9.5 with the 215's. Your probably pretty slow with those charges of Varget. Freebore is not sufficient for those big pills to hit the upper nodes with Varget. I would think you would be getting near compression at 42. I have a freebore similar to yours and get compressed at 42.5 with the 20x bullets so I use 4895 instead of Varget. This is in Alpha brass which has less capacity than Lapua palma brass and even greater amount less than lapua lrp brass so your mileage may vary.

 

[Clancy]

Ok thanks for the explanation.

You’re welcome, you’re getting a lot of responses that are obviously based on nothing but group size, which is irrelevant at this stage.

Tell me, what do you think would happen if you ran a seating depth test with a charge right between your 9 and 10 charges with the 215.

 

[Papa Charlie]

You’re welcome, you’re getting a lot of responses that are obviously based on nothing but group size, which is irrelevant at this stage.

Tell me, what do you think would happen if you ran a seating depth test with a charge right between your 9 and 10 charges?

As I have been re-reading these posts, that is where I will be concentrating my next effort. I plan to refine the load and seating depth around load #9 for both the 200 and 215gr bullets. I don't believe I will get sufficient velocity from the lower load numbers (Loads 5 & 6).

 

[abersfelderami]

200.20x.........#9 +/-.1gr
215...............between #9&10