MIxing lots of .308 Lapua brass?

[DP425]

Okay here's the deal, I some how ended up with three different lot numbers for 1000 pieces of new brass. 600 are one lot, 300 another lot and yet another lot for the remaining 100.

I'm weighing each case and will then break them down into lots once that is finished, so really my only concerns would be the case head size and amount of material varying from lot to lot, and more importantly, the brass being a slightly different alloy that won't behave the exact same way.

Am I getting stupid with this? I mean I know EVERYTHING will have an effect, but is it enough to matter or even be measurable?

For the time being, I'm keeping the lots separate as I weigh it all out. I have a feeling though that I'm taking this too damn far.

THOUGHTS?

 

[Force_Multiplier]

Re: MIxing lots of .308 Lapua brass?

what... are we on a benchrest site.... I've mixed years of LC and still get .5 MOA out to 500yds....Lapua should be at least as good

 

[DP425]

Re: MIxing lots of .308 Lapua brass?

HAHA! Okay... I had a feeling I was starting to take this too far. Never worried about it in any reloading before!

It is interesting that the newer lots (the lot of three are in the new blue plastic boxes, the others are in the old chip-board boxes) are showing consistently that is better than the older ones. Where the older ones went from 172.4gr up to 175gr, these are mostly staying between 172.6 and 174.1.

 

[memo43]

Re: MIxing lots of .308 Lapua brass?

I have about the same as you. it's all mixed in together. I haven't seen or noticed any differance in them

memo

 

[bignada]

Re: MIxing lots of .308 Lapua brass?

My observation is this: Most critical shooting ability, once you reach a point of proficiency, is Between Your Ears.

You are worried about your brass not being "same lot", so your shooting will suffer. Probably not going to matter, but you have programmed yourself to expect that it does...

You are way over-thinking this shit. What do you KNOW about your chamber? Own the reamer that chambered your rifle? Did you specify chamber dimension and maybe obtain a custom ground reamer for your specific bullet and brass? Got throat tailored perfectly to your bullet of choice? Don't have a bullet of choice? Don't KNOW your chamber oal dimension? Don't setup your brass to be .0005" under your fired oal when you size?

If not aware of the variables mentioned above, what the hell are you sweating lapua brass for? Even if you had same lot, wouldn't an anal-retentive shooter weigh all 1000 cases and segregate by weight? Think there ain't no variation there?

Lapua is not "The Promised Land". Not nearly the essential component in the formula so many think.

Chamber-throat-oal dimensions are what are critical. With minimum oal length chamber, your accuracy worries are over.

Lot # is not what matters.
Figure the alloy will be substantially different?
Doubtful.
Weigh your cases if you want to spend several hours ascertaining that you've done all you can do to eliminate variables.

The real variables that matter are chamber related, but if you never worried about them before; now you have other concerns to blame for why all your shots don't go in one ragged hole...

Don't psyche yourself out is my advice.
Get a Wilson chamber gauge or RCBS Precision Mic and learn your chamber variables.

 

[vinconco]

Re: MIxing lots of .308 Lapua brass?

I keep mine in lots of 100 rounds and keep track of how many times they're fired. Brass will work harden and affect bullet tension which will show up on a target.

 

[DP425]

Re: MIxing lots of .308 Lapua brass?

Bignada:

Yeah I'm aware of everything you discussed, and I do have a wilson chamber gauge. However, given my need to mag feed, seating depth is limited on what I can do with it. And of course, these loads are for an OBR; so I certainly didn't spec anything out on the barrel.

And of course I'm also considering trying to make the most accurate load I can for use in any .308 I would want to run match through, as I do have an LTR as well (just don't have it ready to shoot). If I can get good performance out of both with the same load, I'll stick with that. So anyway, I'm trying to keep the variables to a minimum in interest of straight consistency. Sure there is a spread in the weighed lots, but it's kept as low as reasonably possible. I simply do not believe there would be no impact on hit consistency (accuracy) if you fire one load with a case weighing 175gr, then the next weighing 172.1 (which is the heaviest and lightest cases in the whole 1000) That weight is somewhere, and will occupy the combustion area on some location.

Alloy differential; yeah, after the first guy responded and was in line with the doubts I had about it... I decided it didn't matter, weight would have an exponentially larger affect.

When I get my LTR rebarreled, or have a gun built for me I'll look into tailoring loads specific for the gun. OR, if I just cannot get acceptable accuracy out of a general use load for all of my .308's. Does that make sense? Best accuracy possible without being set for a specific gun which may cause shit accuracy on another gun. Obviously requires some testing! Really, just trying to load like FGMM but a bit better.

 

[VKC]

Re: MIxing lots of .308 Lapua brass?

Mixing the lots will not matter much, but if you are worried I don't think you need to do much more than weight sort since Lapua brass is fairly consistent.