Load Change Advice; 30-06 National Match Brass

[Laguna Freak]

How does the internal volume compare to the worn brass. If I have different brass but with nearly identical volume, I load it very close to my established load. If it has greater volume, I load identical and be ready to bump up my charge. Internal volume to me is a better comparison than weight.

Sorry, I was referring to internal water weight. The thread is a bit confusing because I originally posted weights of cases full of water rather than tare weight of water. Tare water weight of worn cases averages 1 to 1.2 gr greater than the Match cases. I figured I would load 56, 56.5, and 57 grains RL 16 behind my 150 AB and see what velocity and pressure signs I get.

 

[William Vogel]

Sorry, I was referring to internal water weight. The thread is a bit confusing because I originally posted weights of cases full of water rather than tare weight of water. Tare water weight of worn cases averages 1 to 1.2 gr greater than the Match cases. I figured I would load 56, 56.5, and 57 grains RL 16 behind my 150 AB and see what velocity and pressure signs I get.

I wouldn’t load any at 57 before shooting the 56. You might be like me and I’ll just pull the bullets but I’d also do 55.8, 56, 56.2, etc. I wouldn’t go to 57 until I fired the brass again and maybe it expanded again.

 

[Laguna Freak]

I wouldn’t load any at 57 before shooting the 56. You might be like me and I’ll just pull the bullets but I’d also do 55.8, 56, 56.2, etc. I wouldn’t go to 57 until I fired the brass again and maybe it expanded again.

I may have gotten my thoughts ahead of myself. I loaded 55 gr for fire forming with cheap 150 gr factory seconds. I reviewed my data and mv ranged from 2842 to 2890.
I still need to move shoulders approx .003” to get to my .002” headspace. I think you’re correct. I need start load well below 56 gr. Maybe 55.5. Your thoughts?

 

[William Vogel]

I may have gotten my thoughts ahead of myself. I loaded 55 gr for fire forming with cheap 150 gr factory seconds. I reviewed my data and mv ranged from 2842 to 2890.
I still need to move shoulders approx .003” to get to my .002” headspace. I think you’re correct. I need start load well below 56 gr. Maybe 55.5. Your thoughts?

My thoughts are that since the new brass has a smaller internal volume that you wouldn’t want to use a charge of equal weight as the old brass, not yet anyway. I also am afraid you might not get the same velocity without over pressure. You won’t know until you work up. I would just load about 5 rounds each starting at about 55.5 like you said. The powder has a bulk density of .890g/cc and water is 1g/cc so you need to back off at least about 1.5 grains to get below your old pressure and it’s a bit more complicated than that because the neck tension and other factors can weigh in. I understand the want for using this new brass but you’re going to have to start with a new slate. Even if you had the exact same brand as what you’re using now, it requires a rework and that’s why I buy twice as much brass as I think I need so the process is as painless as possible. I just store the other pieces until I shoot out the first half. I shoot every piece once and then anneal, size, clean and split it.

 

[searcher]

Please help me understand the potential benefit of your counsel. When weight sorted, I have 2 Lots of brass within a 3 grain weight spread, which is my standard. I have 20 odd weight cases that fall into 2 grain Lots.

Yeah - don't be too concerned with different lots and years, as I assume, shooting the Accubond, you are hunting with it. I just finished prepping a batch of 1,000 Lake City .556 brass for varmint use. They are mixed years. After all brass prep is done (and I do skim turn the necks), I weigh the brass into two lots, based on weight. You can have multiple years all fall within a few grains in weight and that most often equates to similar case capacity. I toss the few outliers on each extreme weight range. In the end, they all will do 1/3 MOA out of an A/R - very close to what I'm able to get using single-lot Lapua. Not a big deal.

 

[searcher]

I may have gotten my thoughts ahead of myself. I loaded 55 gr for fire forming with cheap 150 gr factory seconds. I reviewed my data and mv ranged from 2842 to 2890.
I still need to move shoulders approx .003” to get to my .002” headspace. I think you’re correct. I need start load well below 56 gr. Maybe 55.5. Your thoughts?

I'd shoot 1/2 grain and one grain less and see where that gets you.

 

[searcher]

One thing I have noticed, when comparing most Reminton brass with Lake City is that the Remington actually had an average of .002" thicker necks, for whatever that is worth. When turning necks on A/R brass, that is a consideration that, in order to keep as thick of necks as possible - the Reminton brass actually comes out ahead in that regard. Just won't get as many firings.

 

[Laguna Freak]

Thank you to everyone who offered sage counsel! Its looking like I got this load dialed back in. 3,4,5 are 55.7 to 55.9 gr = 2870 fps 8 fps ES. FWIW; Brass is FA and LC 60, 61, 62. This old Steyr Pro Hunter still driving tacks after 25 years.