Changing load for second brass firing?

[timelinex]

I'm finally honing in on a great load for my 338lm. I am using brand new and prepped lapua brass. I have used almost all my new brass, so I am planning on neck sizing and body sizing.

Is the load going to change? I'm guessing internal dimensions are going to slightly change compared to new un-sized brass. This should mean there would be more or less powder.

I realize that you never know for sure until you try it, but I'm guessing there is a natural trend....

Thanks

 

[MALLARD]

Re: Changing load for second brass firing?

i think if your exiting at the most ideal time ( when the pwaves are closest to the receiver) then i dont think your OBT will change significantly. Might have to increase your charge by a few grains , ( less then .5 i believe) but, i doubt it.

 

[Graham]

Re: Changing load for second brass firing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: timelinex</div><div class="ubbcode-body">Is the load going to change?</div></div>No, but the velocity will - slightly.

 

[BuzzBoss915]

Re: Changing load for second brass firing?

I think it depends on whether you are processing and selecting your cases based on some determination of uniformity. Meaning, weighing or some other means of checking internal capacity.

Then, I like to keep them segregated by marking the headstamp in a certain location. Then they can be tumbled together and you still can identify these cases for subsequent loading, but changing the amount of propellant for fireformed cases, no I don't do it. But, I concede that you may lose a few feet per second, but that doesn't concern me, accuracy concerns me. BB

 

[djtjr]

Re: Changing load for second brass firing?

you should be very close from new brass i can often find my best load and not have to change anything for the second firing most of the time but to be certain i tend to verify using that load plus 2 additional strings of + and - .2 OR .3 grains depending on the case volume just to be sure groups are not significantly better.

 

[Graham]

Re: Changing load for second brass firing?

If a tenth of a grain of powder matters to you, and you are weighing your cases, then you're in the wrong sport: The chamber temp during a stage will change your velocities more than that.

 

[timelinex]

Re: Changing load for second brass firing?

Thanks for all the replies. So from my understanding, there might be a slight change from new to sized/fired, but minimal between firings.

I guess I will use my once fired brass to finalize my load then...

 

[Lt. Arclight]

Re: Changing load for second brass firing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: timelinex</div><div class="ubbcode-body">I'm finally honing in on a great load for my 338lm. I am using brand new and prepped lapua brass. I have used almost all my new brass, so I am planning on neck sizing and body sizing.

Is the load going to change? I'm guessing internal dimensions are going to slightly change compared to new un-sized brass. This should mean there would be more or less powder.

I realize that you never know for sure until you try it, but I'm guessing there is a natural trend....

Thanks </div></div>

Your time would be better spent at the range. Really. You are going to do all that work and then you'll buy another lot of powder that will burn different and you'll want to bash your brains in. IMO, do by all means work on producing good handloads-but don't waste time on things that really don't matter. Size both the neck and body. Case capacity won't vary that much. Temperature and powder lots are going to vary more. Just when you think you have the PERFECT load....

 

[timelinex]

Re: Changing load for second brass firing?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lt. Arclight</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: timelinex</div><div class="ubbcode-body">I'm finally honing in on a great load for my 338lm. I am using brand new and prepped lapua brass. I have used almost all my new brass, so I am planning on neck sizing and body sizing.

Is the load going to change? I'm guessing internal dimensions are going to slightly change compared to new un-sized brass. This should mean there would be more or less powder.

I realize that you never know for sure until you try it, but I'm guessing there is a natural trend....

Thanks </div></div>

Your time would be better spent at the range. Really. You are going to do all that work and then you'll buy another lot of powder that will burn different and you'll want to bash your brains in. IMO, do by all means work on producing good handloads-but don't waste time on things that really don't matter. Size both the neck and body. Case capacity won't vary that much. Temperature and powder lots are going to vary more. Just when you think you have the PERFECT load....

</div></div>

Dont get me wrong, im not looking for the PERFECT load.. but when your shooting out to 2000+ yards, even 10 fps makes a big difference.