Ran another ladder still can’t seem to find a clear path forward

[Randy dawson]

Shot is wind less than 10 mph. From a bench with sand bags. Last group on bottom left was sighting a different rifle. But they are in order left to right, top to bottom. Starting lowest charge working to highest. 4 min between shots for barrel to cool. Started with a clean barrel

 

[sedancowboy]

If I was going to shoot a match I would choose the lowest SD and do a seating depth test.
If it was a hunting rifle I would choose the highest node with SDs at 10 or below and do a seating depth test. I just did this with a 338LP and went from a 1.25 MOA group to a .25 MOA group with one seating depth change. I will remind you that some rifles just will not shoot some bullets or even some brands of bullets. I have a 6 CM that will not shoot the 103 ELD-Xs that I load but will shot factory ammo fine. However it will shoot Berger 105 Hybrids about anyway I load them.

 

[Pinoniper]

Perhaps your rifle just doesn't like that bullet.

 

[david g ranes]

Go back try again with a dirty barrel see if it levels out. David

 

[Dmagna]

Do a seating depth test on the 75.5

 

[Wolf76]

Shot is wind less than 10 mph. From a bench with sand bags. Last group on bottom left was sighting a different rifle. But they are in order left to right, top to bottom. Starting lowest charge working to highest. 4 min between shots for barrel to cool. Started with a clean barrel

This is why I do a seating depth test first. Once the depth is dialed in, watching the nodes open and close is predicable.

 

[Dmagna]

This is why I do a seating depth test first. Once the depth is dialed in, watching the nodes open and close is predicable.

I have had many groups open up on powder charges and then I have tightened them back up by changing seating depth again.

 

[Randy dawson]

If I was going to shoot a match I would choose the lowest SD and do a seating depth test.
If it was a hunting rifle I would choose the highest node with SDs at 10 or below and do a seating depth test. I just did this with a 338LP and went from a 1.25 MOA group to a .25 MOA group with one seating depth change. I will remind you that some rifles just will not shoot some bullets or even some brands of bullets. I have a 6 CM that will not shoot the 103 ELD-Xs that I load but will shot factory ammo fine. However it will shoot Berger 105 Hybrids about anyway I load them.

It is a hunting rifle. This is also the second bullet I have tried first was 190 Berger and I couldn't seem to get it either. I have developed other loads for different rifles and either got lucky or something. Never had this much trouble. Do you have a recommendation for a seating depth test. My plan was to start at lands and work back .003 at a time

 

[Justice1327]

Shot is wind less than 10 mph. From a bench with sand bags. Last group on bottom left was sighting a different rifle. But they are in order left to right, top to bottom. Starting lowest charge working to highest. 4 min between shots for barrel to cool. Started with a clean barrel

Recommend a seating depth test on the 71.5 and 73

 

[Wolf76]

I have had many groups open up on powder charges and then I have tightened them back up by changing seating depth again.

OK... not really sure I understand your point. There's more than one way to skin a cat.
My point is.... once the seating depth is determined, it doesn't change until the throat or bullet changes. Having 1/2 the equation figured out makes the rest of load development far easier. Trying to decipher bad groups is what we're dealing with here and it could have been avoided with any level of seating depth testing.

Back to the OP's question....

 

[GuroChris]

This is why I do a seating depth test first. Once the depth is dialed in, watching the nodes open and close is predicable.

Ok, so this is a real question not being a wiseguy, how do you know which is a safe charge weight to do the seating test with. Sort of a chicken and egg situation. If the shooter is starting from scratch how can he know the selected charge weight for the seating depth test is ok in his/her rifle? but if they work up a charge weight from min to max then test seating depth at the charge that showed the most promise then they also know the charge is good in their rifle.

 

[Dmagna]

OK... not really sure I understand your point. There's more than one way to skin a cat.
My point is.... once the seating depth is determined, it doesn't change until the throat or bullet changes. Having 1/2 the equation figured out makes the rest of load development far easier. Trying to decipher bad groups is what we're dealing with here and it could have been avoided with any level of seating depth testing.

Back to the OP's question....

Yeah except sweet spot of seating depth can change when you change powder load. I have never been able to find a good shooting load by finding seating depth first. I always find powder charge first and then tighten the group with seating depth.

 

[Wolf76]

Yeah except sweet spot of seating depth can change when you change powder load. I have never been able to find a good shooting load by finding seating depth first. I always find powder charge first and then tighten the group with seating depth.

IME, I have found exactly the opposite.

 

[Deputy819]

I've had success doing 'rough' seating depth tests first at minimum/arbitrary charge weights away from a powder node. I then do powder charge work-ups with the tightest group shown. Once I've found my preferred powder charge/node I'll do very slight seating depth 'tweaks' to tighten up (hopefully) even more. This is what has worked for me more often than not, but as previously said there is more than one way to skin a cat.....