Weight or Length??

[foxyloxy]

Hi Folks.

 

When it comes to brass prep, which would be considered more important brass weight or brass length??

 

For example, say i have 100 pieces of once fired brass. Ive cleaned, deprimed & FL sized & then annealed.

 

I then measure said brass by length. I pick out the shortest 5 pieces & the longest 5 pieces to use as foulers. That leaves 90 pieces that I segregate into say 3 groups of similar length - say 30 pieces in each group....

 

THEN... I further seperate the brass into categories by weight, but low & behold some of the brass in the shortest group weigh the same as some of the brass in the next group!! obviously because the wall thickness varies from piece to piece.

 

Is this going overboard?? Which would generally be considered more important in contributing to accuracy or is it purely an individual thing?

 

Thanks in advance

 

FL

[gbal]

I'd suggest maybe going into too much detail-IF you end up with batches that are not clones within the batch!

If the batches were cloned,can do no harm of course....but I'd say you'd need a very good rifle indeed to see any differences consistently on target.

Just as example,even forbenchrest 100y with a stolle 6PPC, I didn't sort in that detail....but then, a harsh critic might say I never won either! (but rifle shot consistent mid twos,without brass segregation).And was capable of a tad better sometimes....

I am rather assuming you are using excellent brass-Lapua,which bypasses most of the sorting issues-it's that good...if not,get Lapua and save some hassle....well worth the slight cost extra.

 

You do need all brass fired to be not exceeding max OAL for chambering/pressure reasons.

 

I'd still say unless you/rifle can shoot sub .25 genuine aggregate for 5x5 shot groups,then the brass work as documented,is probably not important....nor is powder to the precise kernel....or two ..or three...or...

effective consistency does not mean splitting a powder kernel.....

 

There is a lighter (and serious) example of misguided precision from US: ranger officer spots a misfire-pop,no bullet and stops the shooter about to reloas another fround (barrel of course has first bullet lodged in it)...."What oad are you using?" ..."yes.....I use 23 gr of varget ,and I counted each grain individually-I'm certain there are exactly 23 in each case...."

 

Obviously,I don't mean you are making this mistake,but there are grains( weight) and grains (kernels-as in grain of salt!)....

But even correctly done, third decimal absolute precision is seldom needed,or rewarded.....

 

Use Lapua,pretty well good to go from the box,unless you are after a record,and have the rifle etc....

 

Have you actually noticed any on target differnces-that is the 'acid' test?

 

gbal

[Andrew]

Hi Folks.

 

When it comes to brass prep, which would be considered more important brass weight or brass length??

 

For example, say i have 100 pieces of once fired brass. Ive cleaned, deprimed & FL sized & then annealed.

 

I then measure said brass by length. I pick out the shortest 5 pieces & the longest 5 pieces to use as foulers. That leaves 90 pieces that I segregate into say 3 groups of similar length - say 30 pieces in each group....

 

THEN... I further seperate the brass into categories by weight, but low & behold some of the brass in the shortest group weigh the same as some of the brass in the next group!! obviously because the wall thickness varies from piece to piece.

 

Is this going overboard?? Which would generally be considered more important in contributing to accuracy or is it purely an individual thing?

 

Thanks in advance

 

FL

When do you find time to shoot??

You are going way overboard, I think. FL resize in your die and trim all the cases to the shortest case you have. Then you can weigh cases but understand, that weight variances are not just in case capacity and if they were, the difference in capacity is equal to 1/12th the difference in case weight. If you have a case that is 1.2 grains heavier than the next, the load would need to be reduced .1 grains for that case to make all even. Hardly worth the time and effort.~Andrew

[foxyloxy]

As ever George, thatnks for taking the time to reply.

 

Yea, Im using Lapua brass & yes, I measure down to the kernel lol.

 

As for an acid test, last day at the range I was trying out the new magnetospeed. I fired 4 groups with the chrono attached & 4 with it off. All 4 groups with it attached were bigger than without.

 

Off the 8 groups fired, 2 were random weight / length brass, 2 were consistent brass but loaded with a 10 thou jump, 2 were consistent brass with no jump & 2 were consistent brass with 10 thou jam.

 

Out of the 4 decent groups without bayonet attached the results at 110 yards were as follows.

 

Random weight / length brass - 0.53" centre to centre

10 thou jump - 0.33"

No jump - 0.42"

10 thou jam - 0.295"

 

Not exactly scientific but the mixed brass group faired the worst in that exercise.

 

I hate trimming brass so Ive just been "batching" them recently. Ill maybe trim to consistent length again & put away the scales in future.

 

Cheers again.

 

FL.

[Andrew]

As ever George, thatnks for taking the time to reply.

 

Yea, Im using Lapua brass & yes, I measure down to the kernel lol.

 

As for an acid test, last day at the range I was trying out the new magnetospeed. I fired 4 groups with the chrono attached & 4 with it off. All 4 groups with it attached were bigger than without.

 

Off the 8 groups fired, 2 were random weight / length brass, 2 were consistent brass but loaded with a 10 thou jump, 2 were consistent brass with no jump & 2 were consistent brass with 10 thou jam.

 

Out of the 4 decent groups without bayonet attached the results at 110 yards were as follows.

 

Random weight / length brass - 0.53" centre to centre

10 thou jump - 0.33"

No jump - 0.42"

10 thou jam - 0.295"

 

Not exactly scientific but the mixed brass group faired the worst in that exercise.

 

I hate trimming brass so Ive just been "batching" them recently. Ill maybe trim to consistent length again & put away the scales in future.

 

Cheers again.

 

FL.

Good move.~Andrew

[gbal]

Ah....but really you'd have to include a random brass with 10 thou jump-as presented,we have two variables probably confounded-

random brass unknown jump,and sorted brass with consistent (10thou) jump.....as I understand it.

 

What is promising is grouping around the .3s,suggesting a good rig....so sorting brass a bit might just squeeze precision a tad...unless the unsorted brass with ten thou jump or jam also shoots in the .3s....golden rule-vary only one thing at a time so a clear comparison is possible...

 

As for powder (indeed anything) if 50 are loaded,aand any variations are random,then of course any random variation among any 5 selected at rando to shoot,will probably about self cancel/average out!

...or be lost in the noise of wind etc errors.

 

I didn't mean to say it's never worth doing-indeed may be for the very best performance-it can never reduce consistency-just that only at very high levels does it make a real difference,though giving a psychological feeling of confidence is no bad thing,on it's own. Near perfect prep etc means no excuses!

 

Balance with Andrew's 'shooting time' and cost effectiveness,etc. For field shooting,there are too many much bigger error sources,but it never hurts (much) to remove even the small ones-and there may be pleasure in it.

Don't forget the bullets-Bergers are pretty uniform,but not all are so consistent, perfect clones from the box !!

 

Ultimately,the kernels-some have holes through them-and length varies....may affect burn rates...German Salazar once did a great atricle on this, Accurate Shooter,forget the year but it was April 1st...perfection is elusive... :-)

 

g

Maybe .1 grain (weight) matters,but not one kernel (even if that is less than the intrinsic precision and reliability of the scales-check by reweighing several times......judging shooting wind to 1% mph of course..)

[stephentri]

Your best to anneal before FL resizing

[gbal]

A recent PRS blog report of the top 100 PRS shooters( first round cold bore hitson 1-2 moa steels at 200-1200 yards from varied,sometimes unconventional positions) showed that only 9 shooters sorted their brass by weight -the vast majority were shooting Lapua though,pretty uniform from tthe box.

 

Only 9 of the top 100 sorted bullets (by weight if they did,non in the top 20). Most used Bergers -very uniform from the box.

About half weighed powder to sub .1 grain ( eg to 1kernel,.02 grain) in lab grade scales,the other half used .1grain resolution scales.

 

Other disciplines might-or not-benefit from different procedures

 

gbal

[Andrew]

There are so many other ballistic ducks that would need to get into a row, and stay there, before weighing powder to a Nth of a tenth of grain would even begin to have any benefit -even in a clinical sense. If is makes you feel good, great, but in practical terms it's an immense waste of time. Time better spent behind the trigger with loads that demanded lesser attention. JMHO, of course...~Andrew

[foxyloxy]

Cheers again folks.

Yea the random rounds in the first group, consisted of brass at random length and weights plus 139 grain lapua bullets of different weights.

I've a bag rider coming for my AT stock soon plus I'm only getting familiar with my new bi-pod so hopefully the groups can only tighten further.

Thanks again

FL

[gbal]

? "139g bullets of different weights.".....surely this isn't possible...or is this just not too well described??

 

What I meant was to make a meaningful comparison you would need groups from unsorted brass with 10 thou jump and sorted brass with ten thou jump...all with bullets from the same box (any very small weight etc differences in the bullets we can ignore,as they are small and random between the two groups. What you wanted to know was whether sorted brass was better;answered by comparing a sorted brass group and an unsorted brass group,with evertything else the same.

....then any differences can be ascribed to the only variable between the two groups-whether the brass was unsorted or sorted.

 

g

[Andrew]

? "139g bullets of different weights.".....surely this isn't possible...or is this just not too well described??

 

What I meant was to make a meaningful comparison you would need groups from unsorted brass with 10 thou jump and sorted brass with ten thou jump...all with bullets from the same box (any very small weight etc differences in the bullets we can ignore,as they are small and random between the two groups. What you wanted to know was whether sorted brass was better;answered by comparing a sorted brass group and an unsorted brass group,with evertything else the same.

....then any differences can be ascribed to the only variable between the two groups-whether the brass was unsorted or sorted.

 

g

More than possible. I just got done weighing samples of 2K "Match" bullets produced by Federal in a special LOT. They had only an extreme spread of .5 grains with a SD in wt of 0.14 grains. These are very consistent indeed. Sierra Match Kings have logged extreme spreads of a grain and more. A-Max the same in weighed LOTS. They still shot very well. Like I said, a lot of variable out there. The variance of weight in bullets -especially those of hunting/field grade varieties- are why I roll my eyes when someone tells me they are slicing powder granules to make an exact weight.~Andrew

(In fairness though, I've never dealt with Lapua bullets.)

[gbal]

Thanks Andrew....yes,bullets from the same box vary ( as I went on to say,we can assume any such small differences are unimportant,and -for the test- random over the two conditions...)

And your findings pretty well confirm that-any decimal point (lesss than 1 grain) differences are virtually negligible for much shooting-swamped by much bigger factors...

 

I did swither when I put 139 grain ....and decided not to add 'do you mean close to 139,or +/-- .2;.5;.8 grain etc-but to cover every possible nuance does get lengthy-I decided the 'we can ignore..the likely bullet weight differences dealt with the point.

Lapua are very consistent bullets,incidentally.

 

I have yet-despite reading thousands of lab reports- to read a competent replicable summary of even a basic experiment that was under 25 words.(that sentence is 25.0 words!)

Can't be done,recipe for misunderstanding.and more posts to clarify...end of. :-)

g

[Andrew]

Thanks Andrew....yes,bullets from the same box vary ( as I went on to say,we can assume any such small differences are unimportant,and -for the test- random over the two conditions...)

And your findings pretty well confirm that-any decimal point (lesss than 1 grain) differences are virtually negligible for much shooting-swamped by much bigger factors...

 

I did swither when I put 139 grain ....and decided not to add 'do you mean close to 139,or +/-- .2;.5;.8 grain etc-but to cover every possible nuance does get lengthy-I decided the 'we can ignore..the likely bullet weight differences dealt with the point.

Lapua are very consistent bullets,incidentally.

 

I have yet-despite reading thousands of lab reports- to read a competent replicable summary of even a basic experiment that was under 25 words.(that sentence is 25.0 words!)

Can't be done,recipe for misunderstanding.and more posts to clarify...end of. :-)

g

Lapua's reputation precedes it, for sure. We just seldom see them beyond mail-order. With so many different varieties of domestic bullets on the shelves it's hard to find the need to order on-line most of the time.~Andrew

[gbal]

Andrew,if we had only Berger (top quality) and Sierra (top value) we'd get by,pretty well.Add Lapua (euro supply) and what's to complain?!

g

[Andrew]

True that. Our supplies are coming back to the pre shortage days. Some popular Match bullets (6.5's) are still in tight supply, but the rest are at least returning to the shelves -albeit with a 20% price increase. I guess the Government orders filled because I recently bought 2000 of the Federal "Special Operations Technology and Science" (SOST) 130 grain, 7.62mm "Match" bullets for my 300AAC. They were listed as a production over-run and only sixteen cents each. They are largely solid copper with an expanding nose: Why should I buy Barnes TAC-X for twice the cost??~Andrew

[MrCetrizine]

How's the .22lr over there? I've just been told by one of my local shops that they can't get any more CCI.

[foxyloxy]

How's the .22lr over there? I've just been told by one of my local shops that they can't get any more CCI.

Not sure MC, the last 22lr I bought was in November. No problems at that stage.

[Andrew]

How's the .22lr over there? I've just been told by one of my local shops that they can't get any more CCI.

If that directed at me, I can tell you that the supplies of 22LR suck. There has been little or no domestic 22LR available for ages, and what comes in is 5 to 8 times the price it was before CCI. etc simply quit making it.* I was one of the smart/lucky ones. In the past when i saw 22 ammo at a good price I bought case lots. (we're taking years back when i was buying CCI for $125/5000 rnds, Aguila SE for $99/5000) and had 40K rounds when the dry spell started. I haven't bought any of the latest issue at all.~Andrew

 

(* I have read much on UK sites about US shooters "panic buying" all the 22LR. Not the case. When the catalogs/websites from the retail giants likes of Cabelas, Bass Pro Shop, Natchez Shooters Supply, MidwayUSA and others list ammo or components as "Not available from manufacturer. No back order" you can bet it's not being made.)