Long range load development at 100 yards.

[Bc'z]

I was just talking with a guy the other day about blowing a shot, while testing.
I'd personally re shoot 41.6, I'd probably also load a tenth either side of that charge to confirm it's in the middle of a node.
Looking at target groups open and close with each charge increase.
41.6 is also at the bottom of the wave.
This is what jumps out at me, and I haven't had my coffee yet.

 

[Capt. Oblivious]

Thanks BC, i might load a couple from 41.3 to 41.6gr and then see what happens at a 1000m and then play with seating. At the moment they are 30thou af hard jam and would like it if they would shoot from 20thou to 30thou, this chasing the lands thing is why im actually looking to shoot a different bullet to VLDs.

On a side note this is not a BR rifle its a steel shooter so I only need to keep 5 shots inside 1moa from 1100y to around 400y

 

[Capt. Oblivious]

Would you guys mind having a look at this target for me?
Shot it today of an xbag at 110y so not the best setup but it gives me a good idea of whats going on.

Im lookig at 41.3gr and 41.6gr, maybe "spilt the diff" and load up some 41.5gr and play with seating?

Around 41.6 - 41.9gr N160 is where it shoots most 105gr bullets real nice.

If its not clear on the target its a 6 slr, 108gr Hornady ELDs, and VV N160.

Didnt measure speed but it should be around 3130-3170fps at 41.6gr.

Just thinking out loud, that first high shot at 41gr was the 3shot out of a very very clean barrel. I shot 2 for fowlers so might be the clean barrel that didnt settle till shot 3, i had a nice carbon ring before this so n iossod that barrel back to the way its mom send it out into the world before this session.

 

[Capt. Oblivious]

SPJ yes, this 110y thing is new to me. I usaully shoot a ladder at 500 or 800y but it has been raining non stop here for a long time so i tried this. Im open to any suggestions from the guys in the know, we shoot from 1100y to 400y so I need to make a 1moa-1.2moa steal plate sing 5 for 5 at those distances

 

[mikeeg02]

I would reshoot 41.0,41.3, and 41.6 at 200 or 300. There's a lot to be learned by reshooting and at a second distance. Generally speaking, the further the better. (For ease of target readability)

Edit: but only as far as you're comfortable calling conditions

 

[Capt. Oblivious]

I would reshoot 41.0,41.3, and 41.6 at 200 or 300. There's a lot to be learned by reshooting and at a second distance. Generally speaking, the further the better. (For ease of target readability)

Edit: but only as far as you're comfortable calling conditions

Thanks Mike, I have time before the new season starts so will shoot them at 300 from a proper rest

 

[Capt. Oblivious]

Ok so I shot these a little over 300y, no real wind but some weird overcast mirage, hot and humid.

Top row is 41.3gr N160 with OAL going from left to rite 2.830", 2.835" and 2.840"
Bottom row is 41.6gr with OAL going from left to rite 2.830", 2.835" and 2.840".

Looks like there is something at 41.6gr and 2.835".
Think next im going to load at that length and see how 41.5, 41.6 and 41.7gr holds up.

108gr ELDx
N160
Sako brass
Cci BR primers out a 6SLR

 

[mikeeg02]

Looks like there is something at 41.6gr and 2.835".
Think next im going to load at that length and see how 41.5, 41.6 and 41.7gr holds up.

That was going to be my next suggestion, it looks like you are really close. Id like to see just a little less vertical at 300. When you do this test, shoot 4 or 5 shot groups so we can fully see the trends. When I move out farther distance, I typically up the round count so I can either discredit a flier, or more consider the "core" of the group. I realize its still small samples for the haters, but its the method to my madness.

Also, how much temperature difference was there from the previous shooting? Keep records of the ambient conditions when shooting, as you and your loading/shooting improve, you will wish you kept those records.

 

[Capt. Oblivious]

Thanks Mike, yes Ill move up to 5 shot groups now to see how they hold up but that last 2 groups is probably close to the limits of my shooting abilities. I would like to get that one shot that drops on both the last 2 groups a little tighter, maybe 41.7gr might be the number.

 

[Francois]

I'm interested to get your inputs on the attached groups. I'm working on loads for my FTR rifle. 308. 31" barrel. Berger 200.20X using Varget and Palma brass

 

[savageshooter86]

View attachment 1154144 I'm interested to get your inputs on the attached groups. I'm working on loads for my FTR rifle. 308. 31" barrel. Berger 200.20X using Varget and Palma brass

Re shoot 43.6-44.2

 

[Brians356]

It's critical to know for sure if the target shown here is as you viewed it while shooting, or was it rotated 90 degs from what's shown. In other words, which way was "up"? (I ask because the notes on paper are not upright, and your red lines indicating group center as well.)
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[Brians356]

Re shoot 43.6-44.2

I agree, assuming "up" is toward the right in the photo. Those two groups' centers are on the same vertical displacement. I would test 1-grain increments 43.7, 43.8, 43.9, 44.0, 44.1 (and optionally repeat 43.6 and 44.2.).
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[Francois]

Yes. Sorry. The target should be landscape and not portrait. Top of the target is to the right. I'll give it a try and give some feedback after.

 

[jdj71]

I like 42.8/43.0. Are you shooting over a chronograph? Maybe you have more than one node.
Good luck, JD

 

[Francois]

Re-shot 42.7 to 44.1. Changed the seating depth. Speed from 2614 to 2674fps. Shot in landscape

At 43.5, the bottom one I pulled (flyer)

 

[ranger0787]

If you notice, on my targets I have a horizontal line that runs across all the targets. I just measure off of that and I can plot it in a line graph.

Erik,
I am confused. I thought when trying to find an accuracy node, you are supposed to find the load with the least amount of vertical dispersion. I, like many on the boards would have I guess, incorrectly picked the 38.5gr powder charge. I am getting ready to do load development for a .308 Win for long range; Berger 200-20x, Lapua Palma SRP brass, CCI-450 primers, Varget powder, 2013 FTR Chamber with .343NK & .170FB with a 28.625" long 1:9" twist Brux barrel. I was going to perform my load test as follows;

4 x 42.80gr with .020" jump, and increase by .2gr until I hit 44.00 gr of Varget. All seating depths would be .020" jump. So, I should have 7, 4 shot groups all with .2gr powder charge differences. Once on target, what should I be looking for (How to interpret what is best?). Am I understanding that once a charge is chosen, then go back and try seating depth testing of; .040" jump, .030" jump, .010" jump and .010" Jamb?

Thanks
Doug

 

[Bc'z]

Your looking for horizontal poi of your targets. Shoot from right to left looking for charge weights on target that are in line with each other.
It's my belief if you try seating depth in .010 increments you may jump right over a sweet spot and not know it.
Optimum seating windows can be small, I like to move in .003 increments.

 

[Brians356]

Erik,
I am confused. I thought when trying to find an accuracy node, you are supposed to find the load with the least amount of vertical dispersion. I, like many on the boards would have I guess, incorrectly picked the 38.5gr powder charge. I am getting ready to do load development for a .308 Win for long range; Berger 200-20x, Lapua Palma SRP brass, CCI-450 primers, Varget powder, 2013 FTR Chamber with .343NK & .170FB with a 28.625" long 1:9" twist Brux barrel. I was going to perform my load test as follows;

4 x 42.80gr with .020" jump, and increase by .2gr until I hit 44.00 gr of Varget. All seating depths would be .020" jump. So, I should have 7, 4 shot groups all with .2gr powder charge differences. Once on target, what should I be looking for (How to interpret what is best?). Am I understanding that once a charge is chosen, then go back and try seating depth testing of; .040" jump, .030" jump, .010" jump and .010" Jamb?

Thanks
Doug

As I understand the initial stage, the horizontal reference line is to find a node wherein the vertical shift of group centers ceases, indicating a reversal of barrel swing. He's not looking for groups with the least vertical spread at that stage.

PS @Bc'z did I get even partial credit?
-

 

[Erik Cortina]

You guys still following this thread? Hard to imagine you guys haven't figured out that it was an April fools joke. Look at the date it was originally posted!