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noname
02-21-2017, 08:38 AM
How many of you serious shooters take the time to weigh your brass?
If you do,how do you go about doing it? Do you weigh befor or after
trimming,etc...Is there really any benefit of doing so..
The reason I am asking is because I have lots of military brass on hand
and am thinking of using it instead of buying all new brass..I normaly
use Winchester brass...thanks:confused::confused:

Rob01
02-21-2017, 08:47 AM
Never did it and don't plan to. I use quality brass from the same manufacturer and get excellent numbers and accuracy. With a big batch of military brass though there might be different head stamps and years mixed in. I would separate to headstamp/year and then you can check internal capacity or just weigh to get you close.

The Military brass will have a smaller internal capacity than the Winchester so definitely don't use the same powder charge and back down and work back up when using the military brass.

stomp442
02-21-2017, 09:39 AM
Individual brass weight is not as important as internal case volume. What you are wanting is consistency and case volume is the best way to do that. Use the H20 method and spend some time. It's time consuming and tedious but it will improve your loads and results on paper.

cowtownup
02-21-2017, 12:30 PM
Then when you get done firing them you have to tumble them one at a time so you can keep track of how you sorted them... LOL...

noname
02-21-2017, 12:57 PM
Then when you get done firing them you have to tumble them one at a time so you can keep track of how you sorted them... LOL... if I have to do that,then to hell with it..

cowtownup
02-21-2017, 02:05 PM
Tumbling one at a time is a little extreme, but so is weighing the H20 capacity of every case.. I guess the best way would be to start with say 500 pieces of brass and put them into 100 count lots based on case weight or case capacity if you're willing to go that far. I'm not at that point yet, however I'm not going to say I will never do it..

bigedp51
02-21-2017, 05:55 PM
I just bought 300 once fired Lake City 7.62 M80 machine gun brass cases, with 09, 11 and 13 dated cases. Weight sorting is the quick and dirty way to sort brass and I don't plan filling 300 cases with water.

But after reading below I'm going to use a two grain plus and minus limit. I'm 67, have chronologically gifted eyesight and drink too much coffee to go to anything more extreme for my new Savage Hog Hunter. And the 2 grain range is still half the variation of factory Remington and Winchester brass.

After buying two new bags of Winchester .308 brass of very poor quality that had six cases that were thrown in the trash, I bought the LC brass. It took time to prep and uniform the brass but when I finished I think the LC brass was much better than Winchester brass at a fraction of the cost. Plus the Lake City 7.62 cases are made heavy duty and are "Ford Truck Tough".


Match grade Lake City M118LR brass is selected from standard M80 case manufacture and must fall into a two grain weight range.

Case Weight Variation Reduction and Subsequent Ballistic Dispersion Improvements in M118LR
61.24% Of M80 Cases Fall In A Two Grain Range
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwik8LHckKLSAhVFthQKHUplC60QFggcMAA&url=http%3A%2F%2Fwww.dtic.mil%2Fndia%2F2010armamen t%2FWednesdayCumberlandDionneDillon.pdf&usg=AFQjCNF8wrhddngNF-usg8RzdI32kK-Wvg&sig2=3e3t1IOEi2rT7uMi1mAz1A


Below they use one grain weight difference "BUT" many shooters just buy Lapua brass and do nothing to it.

Complete Precision Case Prep
Preparing Cases for Long-Range Accuracy
http://www.accurateshooter.com/technical-articles/reloading/complete-precision-case-prep/

Step 8

Weigh the cases and separate by lots not greater than one grain in weight difference or about 0.5 percent.

Below .223/5.56 case weight and weight variations, and as you can see the Lake City brass is "much" better than Remington or Winchester brass.

http://i.imgur.com/PExmCCk.jpg

Also Nosler custom brass is weight sorted.

noname
02-21-2017, 06:45 PM
I just bought 300 once fired Lake City 7.62 M80 machine gun brass cases, with 09, 11 and 13 dated cases. Weight sorting is the quick and dirty way to sort brass and I don't plan filling 300 cases with water.

But after reading below I'm going to use a two grain plus and minus limit. I'm 67, have chronologically gifted eyesight and drink too much coffee to go to anything more extreme for my new Savage Hog Hunter. And the 2 grain range is still half the variation of factory Remington and Winchester brass.

After buying two new bags of Winchester .308 brass of very poor quality that had six cases that were thrown in the trash, I bought the LC brass. It took time to prep and uniform the brass but when I finished I think the LC brass was much better than Winchester brass at a fraction of the cost. Plus the Lake City 7.62 cases are made heavy duty and are "Ford Truck Tough".


Match grade Lake City M118LR brass is selected from standard M80 case manufacture and must fall into a two grain weight range.

Case Weight Variation Reduction and Subsequent Ballistic Dispersion Improvements in M118LR
61.24% Of M80 Cases Fall In A Two Grain Range
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwik8LHckKLSAhVFthQKHUplC60QFggcMAA&url=http%3A%2F%2Fwww.dtic.mil%2Fndia%2F2010armamen t%2FWednesdayCumberlandDionneDillon.pdf&usg=AFQjCNF8wrhddngNF-usg8RzdI32kK-Wvg&sig2=3e3t1IOEi2rT7uMi1mAz1A


Below they use one grain weight difference "BUT" many shooters just buy Lapua brass and do nothing to it.

Complete Precision Case Prep
Preparing Cases for Long-Range Accuracy
http://www.accurateshooter.com/technical-articles/reloading/complete-precision-case-prep/

Step 8

Weigh the cases and separate by lots not greater than one grain in weight difference or about 0.5 percent.

Below .223/5.56 case weight and weight variations, and as you can see the Lake City brass is "much" better than Remington or Winchester brass.

http://i.imgur.com/PExmCCk.jpg

Also Nosler custom brass is weight sorted.

I read all that with interest and have had others say that LC was good stuff...I tried Lapua in the past..My opinion
was it was junk brass.I had 12 out of 50 split on the first fireing..Also in 223...Like shooting bergers versus sierra.
Sierra was lots better for me...oh well..Thanks for all the info..

Zero333
02-21-2017, 07:17 PM
Separate the brass according to headstamp first and foremost. After that you can segregate into groups within 1 or 2 gr.

I've used the H20 method at the same time as correlating it to the brass weight and my conclusion is that weight sorting to within 1 or 2 gr of each other is plenty good.

Sort the brass after all the prep work.

Phranque
02-21-2017, 10:31 PM
Individual brass weight is not as important as internal case volume. What you are wanting is consistency and case volume is the best way to do that. Use the H20 method and spend some time. It's time consuming and tedious but it will improve your loads and results on paper.

I may have done that 25 years ago when I first started a family and every penny counted, but now the son is grown & gone and I have a good career, my time has become much more valuable than that. Sure, I buy bulk LC for my AR's, but I sure as heck ain't messing with that. Lapua all day long for my bolts.

The Old Coach
02-24-2017, 02:49 PM
That chart should be tattooed on the inside of the eyelids of people who still claim that military brass is heavier!

Once all the cases have been FL sized, weight is a very good indicator of internal volume. I've spent hours dripping water into cases, and trying to get the meniscus to be uniform every time. It's next to impossible, so the variance in the measurements probably is greater than the variance by the simple weight measurement method.

Burr
02-24-2017, 04:58 PM
First off - I've reloaded rifle cartridges for 40 years being completely and totally oblivious to brass weight/case water volume. I'm still alive - huh.

But reloading - is a hobby for me - is sometimes fun to explore different steps to see how important it would be to incorporate into reloading steps.

My opinion - if you are shooting competitively, or simply want to employ every step possible to create the most consistent, repeatable results - it's one step you could perform. I categorize it as a step - when incorporated with 4-6 other steps that have similar effect - might add up to an effect that can be measured to be beneficial. It's a cumulative thing. By itself - might not detect a measurable difference. With several other steps - they may add up to a measurable difference - especially in competition or at extreme ranges.

Eventually I did weigh cases - did not test water volume. I did so on 100 new Lapua brass cases - on a balance beam scale (painful), and sorted brass into some very tight weight groups. I had 87 out of 100 pcs in 2 very tight groups. The other 13 cases became modified cases for my length gauge, sent to die makers for a custom die etc, and load the two groups of brass separate. I have not yet measured a difference in velocity, SD, or target grouping in those two groups.

I may do it again when I plan on shooting more than 300 yards for fun. But I won't be buying an electronic scale just to weigh my brass.

Robinhood
02-24-2017, 05:38 PM
I am curious how many people check H2O without insuring the external dimensions of the case its the same as the others.This is a huge problem with automatic or gas gun fired brass. If you have ever used a Wilson Case trimmer with the Wilson Case holder, you understand that case volume measurement is futile if your external dimensions are different. Manufacturer, lot, weight. I recommend that anyone who thinks their H2O capacity is a barometer of similar brass get a Wilson case trimmer holder to compare external dimensions other than head space or OAL.

bigedp51
02-24-2017, 08:17 PM
Quickload tells you to check case capacity on cases fired in your chamber to get true case capacity.

bigedp51
02-24-2017, 08:24 PM
That chart should be tattooed on the inside of the eyelids of people who still claim that military brass is heavier!

Once all the cases have been FL sized, weight is a very good indicator of internal volume. I've spent hours dripping water into cases, and trying to get the meniscus to be uniform every time. It's next to impossible, so the variance in the measurements probably is greater than the variance by the simple weight measurement method.

Lake City 5.56 and commercial contract 5.56 made for the military use harder brass. You can't make the .223/5.56 case thicker like 7.62 cases because you would loose too much internal volume.

Lake City 7.62 cases have two grains "LESS" case capacity because the base is thicker and also made of harder brass.

And you are to measure case capacity with a case fired in your chamber, because that is the size of your "boiler room".

Robinhood
02-24-2017, 08:48 PM
Quickload tells you to check case capacity on cases fired in your chamber to get true case capacity. This is not for case inspection, it is to come as close as possible to determining the volume at max expansion or otherwise the volume of the case at high pressure and temperature. One case can spring back differently than the next. so two cases fired in the same chamber may exhibit slight differences in external dimension. However the newer the brass the better the chance of those differences being minute.

bigedp51
02-25-2017, 11:40 AM
The point here is you do not check case case capacity with a new unfired case or a fired case from a machine gun with its larger chamber. (and a snug fit in a Wilson trimmer)

You use a case fired in your rifle to get the approximate size/volume of your chamber.

Quickload defaults to the lowest case capacity, and as a example the default .223/5.56 case capacity is 28.0 and a Lake City 5.56 is 30.6. This will make a 6,000 psi difference in chamber pressure between these two case capacities.

Checking case weight or case capacity is nothing more than checking the cases for uniformity.

Bottom line, once fired Lake City brass is more uniform than Remington or Winchester brass at a fraction of the cost of Lapua brass.

Below .223/5.56 case weights and volume.

http://i.imgur.com/PExmCCk.jpg

http://i.imgur.com/LjAQ7L9.jpg

So again military 7.62x51 M118LR sniper ammo is weight sorted with a 2 grain weight variation limit.

Robinhood
02-25-2017, 02:25 PM
Agreed

The Old Coach
02-26-2017, 10:56 AM
Right. Arguing over whether or not you measure fired or sized is irrelevant, so long as you're consistent. And like my weighing of .22 RF ammo, the task is more to identify and cull outliers than anything else.

Unless you believe that Quickload is going to calculate your perfect max-pressure load for you. I use it a lot, but only to get starting loads.

bigedp51
02-26-2017, 03:35 PM
Last night I checked the weight of over 100 Lake City 7.62 cases dated 09, the case weight varied less than 2 1/2 grains. Considering that Remington and Winchester cases would be far more than this these once fired military cases were a good buy and far cheaper than buying Lapua brass.

I also weighed Lake City 7.62 dated 15 and these cases were lighter by approximately 1 grain so the LC cases should be separated by date.

And again I bought the Lake City cases because the last new Winchester cases I bought were of very low quality/uniformity and 6 brand new cases were thrown in the trash.