Load development

[ColeT96]

So I would like some guidance. I have done an ocw test and found a node and verified it by shooting again. Picture below. 83-84gr

Now I worked up from the low end starting at 82.9 gr up in .3 grain increments to 84.1 in 3 shot samples. I will shoot these and look at impact point and find another "node" for accuracy (not sure if that is the correct term) where a couple of charge weights have a similar POI with consistent group shape.

Once that is done I will the move to seating depth for accuracy tuning. Where ever I am wrong in this let me know I'm learning. This is my first time. The gun specs are on the target notes.

Here is my small charge weight testing from today. I ran out of light. I will shoot the rest of the charge weights Sunday and upload them then. But in the meantime, the hybrid has a consistent shape and very close velocity. I know velocity isn't the key here, but when I shoot the VLD 2 big hole and one is a flier and when it does one has a velocity spike. The VLD is .010 off the lands and the hybrid .035 off. Pictured below

Help educate me on all of this

 

[Phil Rizzo]

I'd re-shoot the interesting ones in whatever range of low-high in .1gr increments.
Maybe 83-83.5 or whatever satisfies your curiosity. Then you can identify the center of the stable zone, based on group size/shape and POI. If you have doubts do it twice.
And don't over heat the barrel.

 

[ColeT96]

I'd re-shoot the interesting ones in whatever range of low-high in .1gr increments.
Maybe 83-83.5 or whatever satisfies your curiosity. Then you can identify the center of the stable zone, based on group size/shape and POI. If you have doubts do it twice.
And don't over heat the barrel.

Ok. I've got three more charge weights to shoot Sunday and I will do that. Once I zero that in do I then go to seating depth for fine tuning?

 

[Phil Rizzo]

If needed yes. There are different ways of accomplishing the whole thing, but the same result is achieved.

*some guys take a medium pressure load and find a seating depth that is giving good results, then do a pressure ladder next. You may need to fine tune in the end regardless, but you won't be far off….

 

[MagnumManiac]

Sorry, but, these results are not nodes.
The Satterlee pressure ladder test is what nodes are found at 600.

This is just an OCW test, nothing more.
Going by your groups, you are far from a stable powder burn, maybe it will tighten from seating depth.
What I see is 2 close and 1 outlier.

Cheers.

 

[ammodrew]

One downside, is 3-shot groups aren't statistically significant, I realize it's going to take a long time to shoot groups of 10 rounds or more, but really what I would be looking at is your velocity standard deviations. You can shoot 'em 3 shots at a time to mitigate the influence of barrel temperature, but I usually start looking for significance at 10 shots, and start finalizing when I've shot 100 or so rounds.

 

[ColeT96]

Sorry, but, these results are not nodes.
The Satterlee pressure ladder test is what nodes are found at 600.

This is just an OCW test, nothing more.
Going by your groups, you are far from a stable powder burn, maybe it will tighten from seating depth.
What I see is 2 close and 1 outlier.

Cheers.

Okay. How would you recommend to go about it?

 

[MagnumManiac]

I would start by doing a bullet seating depth test with a middle load of a powder in the middle range of those tested.
Start with 3 round groups at touching, .010" off, .020" off, .030" off, .040" off and .050" off.
Shoot those, take whichever shoots the tightest, then fine tune, +/- .005" from that, then you can do .003"+/- of that number to see if group shape changes.
Then, when you start doing powder testing, the only variable is powder charge, which should be far more precise and will tell you if the burn is correct or not.
2 close, then an outlier suggests both powder burn and seating depth are not correct.

Cheers.

 

[nksmfamjp]

Why are you calling that OCW? What do you think you are getting from that shooting? Are you telling us that 1 round at 83 gr and 1rd at 84 gr being close tells you something?

I'm confused. I call that a ladder test. I too shoot 1 rd at each bullseye. I shoot 10-15 shots. My focus is finding max pressure. I would be lying if I said that I didn't like seeing 3 shots in the same area.

Then I shoot a 10 rd OCW groups x 3-5 in that ball park ….about 0.5gr increments. If I get one in the ball park for group size, I fine tune with OAL.

For OAL, I have a hand press. I load them all long. Then shoot and shorten. So, on group 1, I shoot 3 minimum. If 3 is under my target group size, I keep going. When I blow the group, I move on. If I get to 10, I consider that a win.

Then I shoot 4 groups of 5. If the composite group is under my target, I call it done. The goal is to get to a mean radius that is minute of deer at some yardage.

I find 0.75" 20 shot groups to be very good. Especially under 10 sd. They are about as good as "quarter minute all day, if I do my part" groups, except they tend to still work at 600 yards and tomorrow!

 

[ColeT96]

Why are you calling that OCW? What do you think you are getting from that shooting? Are you telling us that 1 round at 83 gr and 1rd at 84 gr being close tells you something?

I'm confused. I call that a ladder test. I too shoot 1 rd at each bullseye. I shoot 10-15 shots. My focus is finding max pressure. I would be lying if I said that I didn't like seeing 3 shots in the same area.

Then I shoot a 10 rd OCW groups x 3-5 in that ball park ….about 0.5gr increments. If I get one in the ball park for group size, I fine tune with OAL.

For OAL, I have a hand press. I load them all long. Then shoot and shorten. So, on group 1, I shoot 3 minimum. If 3 is under my target group size, I keep going. When I blow the group, I move on. If I get to 10, I consider that a win.

Then I shoot 4 groups of 5. If the composite group is under my target, I call it done. The goal is to get to a mean radius that is minute of deer at some yardage.

I find 0.75" 20 shot groups to be very good. Especially under 10 sd. They are about as good as "quarter minute all day, if I do my part" groups, except they tend to still work at 600 yards and tomorrow!

I don't know either. I'm new to this. That's why I want corrections and a direction

 

[Phil Rizzo]

I would start by doing a bullet seating depth test with a middle load of a powder in the middle range of those tested.
Start with 3 round groups at touching, .010" off, .020" off, .030" off, .040" off and .050" off.
Shoot those, take whichever shoots the tightest, then fine tune, +/- .005" from that, then you can do .003"+/- of that number to see if group shape changes.
Then, when you start doing powder testing, the only variable is powder charge, which should be far more precise and will tell you if the burn is correct or not.
2 close, then an outlier suggests both powder burn and seating depth are not correct.

Cheers.

I'm with him.
It's been my most thorough way to get where I want to be.
And I really like powder being my only change to get to the results I want in the end.
You can move charge weights .3 or .5 or whatever to find what you like, in a ladder test, THEN go down to .1 to establish the upper and lower limits of desirable results, and get in the center.

If you are in the center of the preferred seating depth range, and the center of the preferred powder charge weights, you have a stable AND consistent end result.

 

[ColeT96]

I'm with him.
It's been my most thorough way to get where I want to be.
And I really like powder being my only change to get to the results I want in the end.
You can move charge weights .3 or .5 or whatever to find what you like, in a ladder test, THEN go down to .1 to establish the upper and lower limits of desirable results, and get in the center.

If you are in the center of the preferred seating depth range, and the center of the preferred powder charge weights, you have a stable AND consistent end result.

Well I pulled bullets and am going to hack out to 500 yards tomorrow and redo my ladder. I will post results and hope for guidance lol. I'm learning this so I know I'm calling things wrong like my OCW test lol

 

[Gary in MD]

On a case of that size, I wouldn't waste any time using a tenth of a grain increments.
.5 grain is fine for that sized case. Bullet seating depth changes (once you find a good powder charge) will pay dividends.

 

[nksmfamjp]

Start by shoot in 10 shots at 100yds with this setup.

1 shot per bullseye. 10 bullseyes in one picture.
Use 0.8gr increments. If any charges are out side of books/data limits, don't shoot them.
Use the best rest you have.
Chrono every shot.
Shoot at hunting temp +/- 20 deg.

Did any give hard bolt lift? Ejector marks, etc?

Then look at velocity date and shots for areas where velocities and dispersion are close.

IMO, 500 is too far. It is easy to get conditions mixed with dispersion.