Case weight?

[Knackers]

G'day fellas, of late I have been preparing some brass for my .223 to use for comp shooting.
The case's are all fireformed trimed to length, de-burredand the other night I weighed them up on some didgi scales.
From 130 case's I ended up with 50 that have a weight variance of .8 of a grain.
Is that OK or should I sort through more case's to try and narrow the variance a bit more?

[trevort]

Knackers, how many rounds will you shoot in the comp?

I think the trick is to batch them. Keep same weight together as long as you have enough to get thru a comp

[Ned Kelly]

G'Day knackers,
Nah, I wouldn't worry about weight, I've shot 6ppc cases that weighed all over the place from the same batch, guess what.......they all grouped the same.

Why, because I turned all the necks the same and I believe uniform neck tension (bullet grip) is much, much more important than case weight.

Also, unless the rifle is a purpose built BR (or equivalent) rifle, you wont notice the difference on paper, just worry about the wind and you'll do ok.

hope this helps

Cheerio Ned

[Knackers]

Why, because I turned all the necks the same and I believe uniform neck tension (bullet grip) is much, much more important than case weight.

I'm not being smart, but does neck tension really matter when you've got 40-50,000 PSI behind the bullet pushing?

[Rinso]

knackers,

Yes mate neck tension is very important in maintaining shot to shot accuracy. Its not as important in a hunting rifle as it is in benchrest but its still important.

As far as weight difference goes try shooting 3 or 4 groups with the stuff you weighed out then shoot 3 or 4 groups with the other batch and see how much difference you get .. I think you will be suprised to find that you wont get much difference at all.

cheers
Rinso

[Knackers]

So it sounds like I could of saved myself some time and energy then

[shane]

Hey Knackers, when you weigthed them out how much variation did you find? As in what was the heaviest and what was the lightest?
cheers,
Shane

[Knackers]

lowest was 92.6grns and the heviest was 94.6grns.
The greater amount ie 80% of them were 93.4 to 94.2 grns=.8grn difference. Does that help at at all.

[trevort]

Rinso, Ned

would I be right in saying the only (or best) way to ensure even tension is to neck turn the cases and size with a bushing die?

[Kenny]

Trevort,

would I be right in saying the only (or best) way to ensure even tension is to neck turn the cases and size with a bushing die?

Yep it's a starting point........even though you have turned them down to a perfect thickness, tension variation will occur due to the temper of the metal from case to case, you will also need to batch the rounds as you load them, I find the 'feel' method works well when seating the pills....

I have probably explained that wrong....but 'temper' is the only word I can think of

KY

[trevort]

I think I get what you mean, some will be harder than others.

[Kenny]

yeppies, if you fire these in practise and conditions allow and your ability allows....you may be able to batch them further

KY

[shane]

Knackers,
Thats not bad for mass production cases, i was expecting much more variation. At that you will fine little to no differance between batched and unbatched.

Mass produced cases often have a few very heavy or very light ones among them, which then start to cause problems. But the weighing and sorting you done certainly wont hurt.
cheers,
Shane

PS, Like the guys say neck tension is very important, but in a hunting rifle you will have a multitude of other problems to worry about.