factory loaded brass mixed with bulk brass

[anweis]

Does it matter - accuracy and consistency wise - if i mix brass from factory loaded ammunition with bulk brass, from the same manufacturer, that is?

[kynardsj]

Should be the same if it's the same manufacturer and all of your brass is trimmed to the same length. Where you can get into your gun shooting all over the target is putting the exact same load in different manufacturers brass or using different primers, different bullets of the same weight and sometimes a different can of the same powder that was made at a different time. I learned the hard way from experience if you put the same load in Winchester, Remington and Federal brass you can end up with three different points of impact. Only mixed brass loading I do now is for 38's that I just want to go bang.

[Graybeard]

I generally do it BUT be aware there can be a surprising difference in brass with the same headstamp from different lots.

Once upon a long time ago when bored and had nothing better to do and an electronic digital scale at hand I decided to weigh sort a few hundred cases. What that experience taught me was that all brands generally a fairly similar weight variation to other brands but that the average weight of them do vary a fair bit brand to brand. But what really surprised me most was that within brands their often is a major variance as well.

As a specific example I had a large quantity of Hornady brass some I had fired as factory ammo myself and some I'd picked up elsewhere tho most likely it too started life as factory ammo. There was no obvious differences in headstamp to indicate different lots but there was around 10-15 grains difference in the average weight of the two lots. I had many of both and within each lot the variance was small but there were clearly two distinctly different lots and weights. I've seen this with Remington, Winchester and Federal as well. Why I dunno.

[anweis]

when bored and had nothing better to do and an electronic digital scale at hand I decided to weigh sort a few hundred cases.

Thanks for your replies. I wasn't bored, but i really wanted to know why my 7-08 reloads were inconsistent all of the sudden, since about the time that i mixed 40 cases from factory ammo with 100 bulk cases. Well, i am still getting 2" groups, and i can hunt with that (my tree stand has a 70 yard visibility), but that rifle shot 0.5" groups  before i mixed the cases. I found a mess of case weights and neck thicknesses. I will keep the brass lots separate from now on.
I think that i will rebarell one of our rifles, a 6mm Remington, to 6.5x55, just because i can get high quality brass from Norma or Lapua for it. That cartridge was fussy to reload for, and i suspect that it was due to inconsistent brass.

[Darrell Davis]

Without question, it is always better to keep rifle brass separated as to number of times fired, make AND LOT NUMBER!!!!!!!!

Some years back, I was working with young son's 30/06, trying to develop some good hunting loads.

It was about an hours drive to the range we were using, so wanted to make the trip worth the expense/time.

Loading the series of test loads, I ran out of brass from the son's supply so went to my "brass stash" and picked out some 06 brass.

I seperated the brass as per brand/maker, AND by style/type of head stamp, then trimmed to length and loaded the test rounds using the same brand (Remington) and head stamp style.

This brass happened to be used for the higher pressure test groups, the last two as I recall, and there were two or three pieces of this "stash" brass in each of those 5 shoot groups.

Well, when those rounds got fired, the "stash" cases not only shot out of the groups, but showed excessive presures.

One case went from "trim to length" to inexcess of the "needs to be trimmed length" in that one shot.

I now make it a practice to use mixed and "range" brass for what I call "banger" brass, meaning brass used for practice and reduced pressure loads.

As stated by GB and others above, weighing the brass would be a smart move even with mixed lots of same brand brass.

Keep em coming!

CDOC