Originally Posted by J E Custom
That is not what I said .
I said that the volume test with water did not produce any better results and the other
methods using granules of any kind were very inconsistent and I would not recomend them
under any circumstances because any granular media will compact with different densities
changing the volume for the same weight.
I am a stickler for details (Ask anyone that knows me) and If something will produce better
results I will use use it.
The fact that someone wants to use water in lieu of weighing is not a problem for me just
because I think the "Proper" weight method works as good or better than any other way
to match cases.
And in the case of it being a wast of time (I am assuming you are talking about my not
doing it on short range weapons) like pistols at 25 to50 yards the reason is that SDs
in reasonable ranges are not measurable as far as accuracy at these ranges.
And in fact the very best scenario for accuracy and consistency it to use only one case
and shoot and load it. With the right chamber setup this will give you the best SDs and
ESs because it remains the most accurate in volume . But this is not practical under
hunting conditions for obvious reasons.
The reason I recomend the prep and weigh method is because anyone that reloads
has everything available to do it this way and It works.
I constantly get standard deviations in the 3 to 5 ft/sec range and groups under 1/10 of
an inch in hunting rifles so I will continue to weight sort my brass even if it hair
lips the pope or some of the other people in the shooting world.
I don't tell anyone that there way of doing something is screwed up I will just tell them
how I do it If they ask. If they don't wan't to try it I'm not offended why should you be.
I am allways willing to learn so I keep an open mind and if something is reported to be
better you can bet I will try it and if it does better than the way I "Was" doing something
then I change and adopt the new way.
I am sorry that you are offended by my recommendations because you have not offended
me with yours.
J E CUSTOM
So, JE Custom,
what weight increments do you sort your brass into?
5 gr? 2 gr? 1 gr? 0.5 gr? 0.1 gr?
I just bought 100 pieces of Norma for my 7mm Rem Mag, measured their trim length and weighed them all.
I found one "reject", which was shorter than the rest (and had a pinch in the neck and poor neck trim, upon closer inspection), and weighed a bit less.
Trim length on 99 pieces was very close to 2.490 (about 2.488 to 2.493", as best I can tell with plastic calipers), with the reject being about 2.455".
The weight on 99 pieces was as follows:
Avg: 215.07 gr
So is that tight enough? Or, would you sort these 99 pieces into two or three groups?
I know there are arguments saying that case weight has little or nothing to do with capacity / resulting pressure profile / muzzle velocity / accuracy, . . . but I don't see any real easy/good way to measure case capacity, and I like the looks of your groups.
I am currently getting as good as 0.35" groups out of my 9 lb hunting rifle. If sorting brass by weight will get me down to 0.20" @ 100 yds, I'll do it. If not, I'm going to go start throwing powder for a ladder test.
Hmm . . .
I suppose one could do two ladder tests; one with brass all within 0.1 gr, and another with brass ranging beyond 1.5 gr . . . and then see if there is a difference in the results.
Assuming that brass is 8 to 10 times as dense gun powder
(8.5 gm/cm^3 vs . . ~1 gm/cm^2 ? How densse is gun powder? I can put 70 grains of Retumbo into a case which holds about 4.5 cm^3 of water)
and assuming that ALL of the brass variation translates into capacity variation (a conservative assumption),
and assuming that 0.1 grains of powder variation is acceptable (if you are on a good node),
then . . . one could say that 0.8 to 1.0 grains of brass weight variation is negligible.
If half the weight variation translates into capacity variation, then you can neglect 2 grains of weight difference in your cases.
If 10% translates into capacity . . . well, you get the idea.
I guess I'm superstitious. There are too many variables, and I'm tempted to sort the brass, at least to 1 gr increments.
-C A L