Case weights

[Longcruise]

I've never given much thought to the consistency of cases, but maybe the short time hanging around this forum has me splitting hairs.

Anyway, how effective is it to sort cases by weight. I'm always careful to match headstamps but from there, I have just sized cleaned and trimmed leaving the rest to blind faith.

What are your thoughts on this

 

[QuietTexan]

Sorting by H20 capacity is more likely to produce measurably better results than sorting by case weight, but unless you're keeping brass separated into matching lots (not just sorted head stamp, but the actual production lot of that brand case) then volume based sorting it's pretty far down the list in terms of things that you should be worried about.

To be more specific, what are you shooting and how are you getting the cases for it?

I think you'd get better results easier by buying a new matching set of brass rather than sorting through mixed lots. Also, a lot of the hair-splitting loading tasks are based on you having the rest of your loading and shooting equipment dialed in to the point changes are noticeable.

 

[Pdyson]

I used to sort by weight then by volume when reloading hornady, Winchester, federal and Remington brass. Then I switched to quality brass by Lapua and Peterson and found them so consistent, sorting was unnecessary. Especially since most of my guns are barely sub-MOA shooters and a couple PRS chassis rifles that are capable of a half moa. By switching to high quality brass and annealing after every firing, I find I don't have to go to extremes (sorting and neck turning) with my brass prep to reach my goals for hunting and PRS.

 

[Longcruise]

This is for 270. Some years ago I purchased 500 Remington cases. I still have most BUT some family members also shoot 270 and favor Remington ammo so they have saved the cases and given them to me. I fear that my original purchase may have become polluted.

I just trimmed and weighed 40 rem cases. Except for three outliers, the rest weighed between 194.6 and 196.8. The outliers were one at 197 and two below 194. I didn't toss those three but did toss one that was about .1 shorter than the trim to min trimmer. That one had obvious factory crimp marks on the mouth.

 

[Doom2]

Even Lapua can vary considerably from lot to lot. I've been able to find polluters by weight since any given lot is so consistent.

As for sorting by weight, within a lot, may or may not be of value. It depends on the level of accuracy you require. As noted, volume is the better guide, but it's a PITA to do.

 

[MagnumManiac]

Case weight within 2-3 grains means very little in volume difference.
After trimming flash holes in 100 cases, the trimmed brass shavings from most brands weigh around 35 grains….so how much weight difference is there going to be with cases that have a burr and those that don't?
Also, many cases, including Lapua, Norma and other top brand cases often have an extractor groove that is cut eccentrically, this will alter the weight of those in comparison to those that are not eccentric.
I check actual volume using a Burette that is graduated for tenths if CC's. This is the only way I know to get consistent volume readings. Without doing this tedious testing, I would get fliers.
Case weight means very little to me.

Cheers.

 

[QuietTexan]

I check actual volume using a Burette that is graduated for tenths if CC's. This is the only way I know to get consistent volume readings. Without doing this tedious testing, I would get fliers.
Case weight means very little to me.

Cheers.

I've heard you mention the burette several times and have been wanting to ask. Do you fill the case then dump into the burette? Or fill the burette to say 6mL, fill the case, and if you have 1.3mL left over say the case is 4.7mL?

I use a pipettor to load in a set volume to each case and then top it off with a dropper, and it takes forever, so I'm up to using a burette if it's faster.

 

[MagnumManiac]

I've heard you mention the burette several times and have been wanting to ask. Do you fill the case then dump into the burette? Or fill the burette to say 6mL, fill the case, and if you have 1.3mL left over say the case is 4.7mL?

I use a pipettor to load in a set volume to each case and then top it off with a dropper, and it takes forever, so I'm up to using a burette if it's faster.

No, the Burette is graduated in whole CC,s with tenths in between.
So you fill it, I use isopropyl alcohol, open the petcock and drain to whole number. I like to start at 50 or even 100 because it is easier to read. Fill the case without a meniscus, usually, I fill to top of shoulder, not into the neck as this occupied by the bullet. Then just calculate what was drained out.
Either way, this is very tedious, but is accurate. I use this method in my job as building engines measuring combustion chambers and intake runners etc to work out displacement and compression numbers.

Cheers.