How much of a weight difference between brass will change the performance of the load.
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How much of a weight difference between brass will change the performance of the load.
you need to weigh your brass with water in the cases to actually know if the weight will effect performance...the actual weight of the case dont matter its the case capacity that makes the difference.Quote:
Originally Posted by troutdiver
This has been proven to be somewhat true over and over again. However one has to question if brass is trimmed to length, flash holes debburred and all external dimensions being very similar(i would assume post sizing), where can the extra weight reside in the heavier cases?Quote:
Originally Posted by LongRange
I wanted to go to the trouble of sorting cases by weighing the water, after ten I found the difference to be astounding on cases with the same dry weight. I had noticed in my reloading infancy that when trimming cases some had to be sized with a small base die just to get them to protrude enough for the Wilson cutter to remove brass and not cut steel. By default the Wilson case trimmer holder I used allows you to determine how much spring back that your case body has after sizing. Here is an example.
[edited;(I was using a 308 and 223 wilson case holder not this WSSM version)]
http://www.varidecicognani.it/downlo...grandi/802.jpg
After some time I started to sort my cases after trimming and sizing first, by weight secondly then by how far the slid into my Wilson case trimming body. This is not my photo but what I experienced after full length sizing, I had some that protruded considerably out of the small end and some did not extend enough to trim. The ones that came up short were remedied by using a small base die. I noticed that when I sorted cases that weighed the same and fit into my holder the same depth that water weights were within the tenth's of grains. So in my opinion when someone goes about sorting cases by weight, if your external dimensions are very similar, case weight is relevant. MHO. Thoughts?
Since I'm not a "precision" shooter, just a hunter and casual target shooter, I sort cases first by head stamp; then by weight (after resizing, cleaning flash holes, and trimming to length). I then select the cases I want to reload based on how I sorted them out, attempting to load groups of cases that are the closest to the same weight by making "bandwidths of tolerance." 1) Cases that weigh the same; 2)cases that weigh within .3 grain of one another; 3)cases that weigh within .5 grain of each other. All the rest of them that are beyond the .5 grain bandwidth go into a "plinking case" box that I'll use when I want to cook up some loads just to get some trigger time or work with a new rifle/scope combination. It's not a very scientific approach, but it serves me well for my purposes.
In principle, if the brass itself is displacing volume, you're looking at about 10 grains of extra brass to reduce case capacity by 1 grain.
In practice, there are much bigger differences between case capacity and case weight between brass from different lots and different manufacturers than between different cases from the same lot and manufacturer. A good cleaning can also be important to uniform case capacity.
Lapua and Nosler brass shows excellent uniformity of case weight and capacity, especially if you do not mix lots. Use good brass, clean with STM, and don't worry beyond that.
I did the sorting with .223 Remington and shot out to only 200 yds. It proved to be a waste of valuble time. If you do the sorting with water,alcohol or even with H380 powder which a lot of us do, in the short range sessions it is a waste. If you are shooting way beyond and are shooting cheaper brass then sorting by volume is the way to go.
I have a good friend who won the agregate award twice at williamsport, using a lefty Savage action yet.
That requires shooting the best average group for all the matches in that year.
He attributes his success to having a barrel block, a good barrel, and good loads.
He sorted his brass by shooting them, period.
He sorted them as to where they landed on paper @ 200 yds and color coded them accordingly.
His son also won the award at age 18, as did his sons friend and him also with a lefty Savage action.
He loaded for them also.
He also made sure all his rounds went into the chamber the same way as for runout by marking the head of the case.
He's also very burned out and rarly shoots anymore lol.
yobuck, I like your friend's approach! For my single shot 6PPC, (my most accurate rifle) I always marked the case heads so that when I inserted a round it would always have the same orientation in the chamber, but I never thought about sorting the brass according to how accurate the shots out of that brass were. Makes some sense to me to do it that way, so when and if it ever warms up around here (never got above freezing all day long, which is very rare here in CenTex!), I'll be trying that method of sorting and grouping my brass.
im sure you have read my nosler brass review thread if not take a look... http://www.savageshooters.com/showth...n-brass-reviewQuote:
Originally Posted by Robinhood
now in that thread i bought a box of 50pcs from powder valley that weighed 180. something grains empty...i bought 2 more boxes from sportsman that all weighed in the 160. something range but ALL 150pcs were with in a grain or less when weighed with water. now i never weigh empty brass because i dont care about the empty weight i only care about case capacity...if you have a case that weighs 50g with water and one that weighs 49 or 51g with water then thats going to cause fliers.
when i weigh my brass i dont weigh it out of the box because its not uniformed to my chamber...first i uniform all my brass...then fire form,then i STM tumble.then size and trim the necks...now the brass is as close to perfect as its going to get then i weigh with water.
if you weighed cases out of the box or after resizing then thats where your huge difference came from...i use a redding body die every time and have it set to what the shoulder was after the first time i fired it...that keeps everything the same every time...i anneal and trim every second firing and STM tumble every time...there are also a few other things i do but you get what im saying...now none of this is worth the time if your not shooting past 400 or so yards...it all comes into play out far.
I apologize for not being more clear. The case is tapered. If you slide it into a tapered female hole, like a taper ring gauge, without force and one goes in further than the other, then the capacity of the case will differ all other things considered equal. So my assertion was that if a case springs back more than another case then you really don't know what you have. Its random at best. The only way that measuring your cases means anything is if you compress the case into the body or full length sizer and check the volume held in a uniform position. Sometimes we get things in our head and it makes us feel better but it is often meaningless if you attempt to get it down to the nats rear. GGMM ammo is a perfect example of what matters. It really doesn't do anything except satisfy your need to be anal. BTDT 20 years ago.
Thanks for all the info. My question is right up there with do you break in a barrel or not. It sounds like it depends on how nit picky I want to get.
i agree 100% that you will never get things perfect...i have the same gauge and trimmer BTW...and you are also right about SOME things that probably dont do much but make us feel better.but consistency is the biggest factor in accuracy....lets say you go out with once fired lapua brass(first time was just to fire form)that you fully preped,PP uniformed,weighed with H2O,STM tumbled and your shoulders are at 1.123" after fire forming and with that brass right away shoot a few 5 shot bug hole groups with 43g H4350 a BR-2 primer a 142g SMK with .003 neck tension...now your a happy man right!?! so you run home load up 10 rounds real fast(with the same brass you just fired)and head back out to confirm the loads only to find that the loads you shot earlier dont shoot so well now...they group well but not bug holes...now your wondering WTF? right? the only difference is you didnt tumble and your brass has now been fired 3 times...now your asking yourself what happened?Quote:
Originally Posted by Robinhood
my point is that if every thing is not the same with your brass every time it can and will cause accuracy issues so the more things you can control and keep consistent the less time you spend wondering why your riffle wont shoot the same group as it did yesterday.
thats a whole other can of worms lol....factory barrel id just shoot...i just change the barrel on my 260...shilen select match...i shot 1 cleaned for the first 5 and was pulling a bit of copper...shot a 5 shot group and cleaned 3 patches copper was gone...shot 44 rounds went home and 5 patches copper was gone. i do this because it makes me feel all warm and fuzzy...ive done the full on shoot and clean for 50 rounds and ive just shot them and have never seen any difference...i shoot and clean to see if the barrel is going to be a heavy fouler not so much to break in.Quote:
Originally Posted by troutdiver