Grouping brass by weight

As long as all those bullets go in the same hole....

It's all good.

I have been very interested in the new loading tech and powders that are being used in SR BR of late.

I can see some very positive spill over into every accuracy discipline.

Groups are approaching the microscopic.

Good stuff indeed...

Jerry
 
Take note those guys shooting those small groups, don't try and measure the volume of fired brass... Many will sort by weight however.
 
Boomer said:
I know I'm going to get stomped for disagreeing with Obtunded and Mystic, but IMHO, if you sort your brand new untrimmed, non-uniformed, brass by weight prior to neck turning or reaming, and provided that all that brass comes from the same manufacturer and case lot, you are sorting by volume. Once you have trimmed and uniformed primer pockets and flash holes, and turned the necks, then I agree, there is no way of knowing what it is you are weighing. Once the brass is sorted into groups, there is no need to move it from one group to another throughout its life.

As for whether or not it is a wast of time, when shooting at extreme long range or when shooting in competition, if you can measure it, it matters, and if sorting brass into groups of +/- .5 gr makes you feel better, even if the results on the target don't necessarily show any difference on any particular day, then it is worth it. With an electronic scale it doesn't take very long. If you believe there is a variable you can control, and you control it, that will make you more confident of your ammo, and confidence wins matches. Consider that a difference of 25 fps will produce a vertical spread of 2" at 1000 yards, and keeping the extreme spread of your ammo's velocity to single digit variances requires a high degree of attention to detail, and a uniform velocity spread is but one element of what makes accurate ammo.
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Boomer
Mentioned this which to me is way more important than 1/2g weight or more of case weight.

. Once you have "trimmed and uniformed primer pockets and flash holes, and turned the necks,"
All of Boomers ways of case prep is in my opinion manditory. I even turn base of cartridge flat.
manitou
 
I plan to mostly group shoot at the range, and use it for some hunting. I am just trying to see if I can get my group size down and trying to tighten up my reloading procedures.
Also I live in a house with three women so I spend lots of time in the "man shed" so I can take the time to be picky!
 
rpollock said:
Take note those guys shooting those small groups, don't try and measure the volume of fired brass... Many will sort by weight however.
Click to expand...

And at one time, weighing charges was a waste of time. Now, some top shooters are going to some pretty long lengths to weigh their charges.

Also, there are a number of things that would be of no relevance to a SR BR shooter that would matter a lot to an F class shooter. Which could be very different from that of an unlimited LR BR shooter.... Or LR BPCR shooter.

I try and keep an open mind and explore ALL forms of shooting. There is always a new thing to learn from another discipline that can help you in yours.

Jerry
 
One of the best ways to deal with it is:

If you have ie, 500 rounds loaded for matches and have not sorted the brass then weigh the loaded rounds and sort them by order of weight. Shoot them from one end to the other in order so any shot in a match will have a very small progressive deviation. You may not use a few extreme at each end of the 500 but most will be very close within the 17 or so that you need.
 
is not the yield strength cartridge brass around 52000 psi? if so most of us are over the yield strength of our brass
 
madman25 said:
is not the yield strength cartridge brass around 52000 psi? if so most of us are over the yield strength of our brass
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It must be higher or else every magnum rifles will have issues with extraction.

62 to 65000psi is the magnum standard and most brass for modern chamberings have no issue dealing with these loads. Go above or multiple firings and things work harden or stretch.

Ian, I have heard this method of sorting ammo. Sounds interesting.

an adaptation might be to reduce your load slightly to account for increased barrel heat and fouling.

Then I guess you could have one batch of ammo for major ambient condition changes.

But it would keep the rifle in tune..... wonder how hard it is to build a barrel tuner :)

Jerry
 
it must be higher than yield otherwise our cases would not get longer. because of the chamber support the case can only go so far and there will still be an elastic portion of the cases expansion on top the the plastic deformation that happens. This will allow the case to contract slightly, IMHO
 
mysticplayer said:
But it would keep the rifle in tune..... wonder how hard it is to build a barrel tuner :)

Jerry
Click to expand...

Just ask Browning how hard it was to build their B.O.S.S system. :D

I was intrigued by the physics of the whole thing, so I used my lathe to thread the barrel on my old 597 with a 14tpi thread. Attached a hunk of aluminum threaded the same, with a hex set-screw. If you were careful and consistent in your shooting mechanics, you could observe major differences in the barrel harmonics dialing that damper in or out by just a few turns of that coarse 14tpi.

I don't propose doing the same to a target barrel; just saying that for my 597 I could get it tuned up between brands of ammunition quite nicely. T99 subsonic sure didn't shoot with the same tune as Remington Yellow Jackets! ;)

-M
 
We have a local shooter who messes around with a barrel tuner on his F-CLass guns.

You would REALLY have to know what the effects will be before you adjust it.

Voodoo science if you ask me.
 
See, for me, I used the tuner to adjust the length between 'nodes' for a given VELOCITY. For F-class or BR shooters, or even Tac Rifle shooters, you've got a load that's pretty consistent and doing node-antinode tuning with length is sort of pointless. Whereas with that 597, I could actually watch my groups shrink as I turned it when switching from subsonics to hi-velocity loads in .22LR. It's all about the mathematics of the physics behind barrel whip, and trying to get your barrel end to be a motionless "node"... which is the EXACT same thing guys do when they "ladder" test loads at long range - just in that case, you're adjusting velocity, wave propagation, and time-of-travel using the bullet instead of a tuned length on the barrel.

Sort of hard to do it that way with a .22LR! :D

-M
 
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