If anyone's sorting cases the 270Win go into the bag marked "For The Raven - BRING TO MISSEDATHON".
Subtle aint I ?
PS. A mate was bleating about each round he fires costing $1, and how expensive that was. I told him he better check current LGS prices again. $1 per round may be fine for WWII milsurp ammo but anything produced this century is reaching $2 or more. He was shocked
Sorting cases
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- .257 Roberts
- Posts: 785
- Joined: Sun May 25, 2008 9:43 pm
- Favourite Cartridge: 7 SAUM
- Location: Singleton, Hunter Valley, NSW
Re: Sorting cases
I usually weigh all cases once they have been annealed and sized and then put them in the 100 round ammo box from lightest to heaviest. This is super simple to do with each 100 round box.The Raven wrote: ↑Mon Sep 17, 2018 7:44 pm When measuring case volume how to you take into account the primer pocket, flash hole size etc?
Do you leave a fired primer in, tape over the primer opening at the case head or what?
0.05ml may be attributable to how you account for the primer pocket, flash hole, what primer you used, and how deeply seated it is...that is when measuring case volume with a liquid.
Just a thought.
I have water weighed 1 batch of 600x 7mm SAUM cases which were in a batch varying by 1.5gns. I used a 21st century shooting primer hole plugs to stop the water from coming out. Each case was annealed after firing, then sized. All cases were already prepped. I did find a general correlation between case weight and volume, but not absolute correlation, so I will still volume sort another batch if i get another big batch of ammo to use for long range, big competitions. With my SAUM cases I found water volume varied by about 0.6gns of water over the 600 cases (which varied 1.5gns in weight).
I found my method of weighing with water was pretty accurate, down to 0.05gn of water. I know this as my first 50 or so cases I hadnt zeroed my scales, so decided to fire them again and reanneal and size them, then water weigh again and they were all pretty much spot on (Minus the small amout that the scale was out of calibration).
Out of curiosity, I took 4 cases which were at extreme weight ends of a bigger batch and varied by about 5gns in weight I think. The water volume only varied by 0.4gns in this limited sample, so correlation between case weight and volume is not absolute.
- frakka
- 22-250 Remington
- Posts: 595
- Joined: Thu Oct 09, 2008 11:43 am
- Favourite Cartridge: 223 Rem
- Location: Central Wheat Belt WA
Re: Sorting cases
It's a big ask to meaningfully correlate weight/volume difference between brass SG = 8.5 and water SG = 1The water volume only varied by 0.4gns in this limited sample, so correlation between case weight and volume is not absolute.
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- .17 HMR
- Posts: 194
- Joined: Tue Nov 04, 2014 4:02 pm
- Favourite Cartridge: .284Win
Re: Sorting cases
As I stated in a previous post about case volume in the lighters and heaviest cases. At Townsville on Saturday, I fired both these case twice to get them fire formed in my chamber. This afternoon I wiped down these two cases and scrubbed out the necks. I left the spent primers in and weighed them. Case (1) 205.0 grns. Case (2) 212.3 grns. Filled with metho, case (1) 258.5 grns. Difference 7.3 grns.
Case (2) 265.0 grns. Case (1) metho weight 53.5 grns. Case (2) metho weight 52.7 grns. That gives a metho volume weight difference of .8grn.
I think that this small difference in full case capacity would diminish to bugger all air space difference after a powder charge and projectile seated. So I M H O. weight sorting cases is a waste of time. These were Winchester cases and I am sure a better brand of cases would not have this sort of variation, making my point more valid. I know others will disagree with me but each to his own. Where the extra brass is I do not know or care, but I suspect in the base.
Cheers,
Trevor.
Case (2) 265.0 grns. Case (1) metho weight 53.5 grns. Case (2) metho weight 52.7 grns. That gives a metho volume weight difference of .8grn.
I think that this small difference in full case capacity would diminish to bugger all air space difference after a powder charge and projectile seated. So I M H O. weight sorting cases is a waste of time. These were Winchester cases and I am sure a better brand of cases would not have this sort of variation, making my point more valid. I know others will disagree with me but each to his own. Where the extra brass is I do not know or care, but I suspect in the base.
Cheers,
Trevor.
Last bumped by Old Trev-39 on Mon Oct 08, 2018 8:04 pm.