Myth Confirming - Sorting Brass for More Consistent OAL on Progressive Press

[LiveLife]

When reloading with mixed range brass on progressive press, ever wonder why you get some crazy swings in OAL?

Some of you may have heard/read the notion, "Sort your brass for more consistent OAL" ... "And to reduce flyers" by bullseye match shooters.

As well documented by "Myth Busting Neck Tension and Bullet Setback" thread that different headstamp brass come with varying levels of case wall thickness and bullet setback, this "Myth Confirming" thread will illustrate why sorting brass by headstamp (Even to resized case length) will reduce finished OAL variance - https://www.thehighroad.org/index.p...neck-tension-and-bullet-setback.830072/page-4

When I tested the new Lee Pro 6000 for finished OAL consistency in progressive mode (shellplate full), various headstamp brass produced different amount of OAL variance - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-3#post-12446468

• RMR 115 gr FMJ RN sized around .3555" were used
• Case mouth was flared to .380" at Station #5 (Used .750" length resized case to set the flare amount)
• .378" taper crimp was applied (Used .750" length resized case)
• Bullets were seated and taper crimped in same step at Station #6

• Blazer unsorted - OAL of 1.128"-1.133" (.005" variance)
• G.F.L. unsorted - OAL of 1.129"-1.133" (.004" variance)
• .FC. unsorted - OAL of 1.128"-1.131" (.003" variance)
• FC unsorted - OAL of 1.130"-1.132" (.002" variance)
• WIN unsorted - OAL of 1.131"-1.133" (.002" variance)
• R-P unsorted - OAL of 1.133"-1.134" (.001" variance)
• R-P "." unsorted - OAL of 1.134"-1.135" (.001" variance)

What some of you may have missed from above data listing were two reloading variables:

1. Mixed "unsorted" resized case length variance affecting OAL range listed
2. How shallow or deep the same bullet was seated to in progression depending on headstamp of brass

So using above sample of mixed range brass, total swing in OAL variance could be .007" (1.128" to 1.135"):

• Sorting brass by single headstamp could reduce OAL variance from .005" down to .001"
• Sorting brass by resized case length could reduce OAL variance further

Reduce progressive press running full shellplate OAL variance to even less than .001"? How?

[NOTE: Both Pro 6000 and Pro 1000 (Along with Pro 4000) utilize ram under station #1 design (Instead of center of shellplate) where resizing force has less affect on shellplate tilt/deflection. Further for Pro 6000, using station #6 next to station #1 to seat/taper crimp in progressive mode may produce less OAL variance than using stations #3/#4/#5]

When I tested 2023 Lee Pro 1000 for finished OAL consistency in progressive mode (shellplate full), I got the following results - https://www.thehighroad.org/index.p...pro-1000-unboxing.916672/page-2#post-12569726

• Blazer unsorted - OAL of 1.128"-1.131 (.003" variance)
• FC unsorted - OAL of 1.129"-1.132" (.003" variance)
• .FC. unsorted - OAL of 1.129"-1.131" (.002" variance)
• R-P unsorted - OAL of 1.132"-1.134" (.002" variance)
• R-P "." unsorted - OAL of 1.133"-1.135" (.002" variance)
• WIN unsorted - OAL of 1.133" (.000" variance)

But wait, why did "WIN" headstamp brass produce .000"/No variance when "WIN" headstamp brass produced .002" variance for Pro 6000?

I have a sneaking suspicion that randomly selected WIN cases may happened to have very close resized case lengths even though they were "unsorted" by resized case length. (I plan on doing some more OAL measurements with WIN headstamp brass with same/different resized case length)

CONCLUSION: Myth is confirmed as to sorting brass by headstamp will reduce OAL variance when using progressive press.

 

[Atavar]

What does sorting brass have to do with OAL? OAL is a function of the adjustment to the seating die and has nothing to do with brass. The seating die is going to push the bullet in to "x" distance from the case holder regardless of the brass in the case holder.

Now if we were talking about case length or flare and crimp it would be another story.

 

[AJC1]

When reloading with mixed range brass, ever wonder why you get some crazy swings in OAL?

Some of you may have heard/read the notion, "Sort your brass for more consistent OAL" ... "And to reduce flyers" by bullseye match shooters.

As well documented by "Myth Busting Neck Tension and Bullet Setback" thread that different headstamp brass come with varying levels of case wall thickness and bullet setback, this "Myth Confirming" thread will illustrate why sorting brass by headstamp (Even to resized case length) will reduce finished OAL variance - https://www.thehighroad.org/index.p...neck-tension-and-bullet-setback.830072/page-4

When I tested the new Lee Pro 6000 for finished OAL consistency in progressive mode (shellplate full), various headstamp brass produced different amount of OAL variance - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-3#post-12446468

• RMR 115 gr FMJ RN sized around .3555" were used
• Case mouth was flared to .380" at Station #5 (Used .750" length resized case to set the flare amount)
• .378" taper crimp was applied (Used .750" length resized case)
• Bullets were seated and taper crimped in same step at Station #6

• Blazer unsorted - OAL of 1.128"-1.133" (.005" variance)
• G.F.L. unsorted - OAL of 1.129"-1.133" (.004" variance)
• .FC. unsorted - OAL of 1.128"-1.131" (.003" variance)
• FC unsorted - OAL of 1.130"-1.132" (.002" variance)
• WIN unsorted - OAL of 1.131"-1.133" (.002" variance)
• R-P unsorted - OAL of 1.133"-1.134" (.001" variance)
• R-P "." unsorted - OAL of 1.134"-1.135" (.001" variance)

What some of you may have missed from above data listing were two reloading variables:

1. Mixed "unsorted" resized case length variance affecting OAL range listed
2. How shallow or deep the same bullet was seated to in progression depending on headstamp of brass

So using above sample of mixed range brass, total swing in OAL variance could be .007" (1.128" to 1.135"):

• Sorting brass by single headstamp could reduce OAL variance from .005" down to .001"
• Sorting brass by resized case length could reduce OAL variance further

Reduce progressive press running full shellplate OAL variance to even less than .001"? How?

[NOTE: Both Pro 6000 and Pro 1000 (Along with Pro 4000) utilize ram under station #1 design (Instead of center of shellplate) where resizing force has less affect on shellplate tilt/deflection. Further for Pro 6000, using station #6 next to station #1 to seat/taper crimp in progressive mode may produce less OAL variance than using stations #3/#4/#5]

When I tested 2023 Lee Pro 1000 for finished OAL consistency in progressive mode (shellplate full), I got the following results - https://www.thehighroad.org/index.p...pro-1000-unboxing.916672/page-2#post-12569726

• Blazer unsorted - OAL of 1.128"-1.131 (.003" variance)
• FC unsorted - OAL of 1.129"-1.132" (.003" variance)
• .FC. unsorted - OAL of 1.129"-1.131" (.002" variance)
• R-P unsorted - OAL of 1.132"-1.134" (.002" variance)
• R-P "." unsorted - OAL of 1.133"-1.135" (.002" variance)
• WIN unsorted - OAL of 1.133" (.000" variance)

But wait, why did "WIN" headstamp brass produce .000"/No variance when "WIN" headstamp brass produced .002" variance for Pro 6000?

I have a sneaking suspicion that randomly selected WIN cases may happened to have very close resized case lengths even though they were "unsorted" by resized case length. (I plan on doing some more OAL measurements with WIN headstamp brass with same/different resized case length)

CONCLUSION: Myth is confirmed as to sorting brass by headstamp will reduce OAL variance.

It doesn't say, but I'm inferring that seating and crimping were separated during these tests?

 

[AJC1]

What does sorting brass have to do with OAL? OAL is a function of the adjustment to the seating die and has nothing to do with brass. The seating die is going to push the bullet in to "x" distance from the case holder regardless of the brass in the case holder.

Now if we were talking about case length or flare and crimp it would be another story.

Seating is effected by case thickness and composition, which directly relates to neck tension... oal varies by resistance to seating. If we had an Amp press you would see that graphed out... I don't have one, but he may. They are quite spendy.

 

[mcb]

If I am loading rifle ammunition to shoot wee-little groups at really long range, then yes sorting is important. In fact for that application I keep brass sorted by production lots and don't mix lots even if they have the same head stamp.

Handgun ammunition I have never found the need but I don't shoot bullseye. My random range brass will keep them in the alpha zone at 50 yards if I do my part and that is more than accurate enough for my handgun uses.

 

[LiveLife]

What does sorting brass have to do with OAL? OAL is a function of the adjustment to the seating die and has nothing to do with brass.

If you are reloading on progressive press where case base is captured within the shellplate, effects of shellplate tilt/deflection can be a variable to affect OAL variance.

[BACKGROUND: Dillon 550 utilizes shellplate design where case base is not captured within the shellplate and case base actually rests on top of fixed subplate/carrier. (Dillon 650/750 utilizes shellplate design where case base is captured within the shellplate). Most progressive presses utilize ram in the center of shellplate design and rely on some sort of subplate system to support the shellplate but still can experience shellplate tilt/deflection to influence OAL variance. Lee Pro 6000/4000/1000 all utilize shellplates that capture case base BUT use ram under station #1 design and floating shellplate design that drops down flat on top of shellplate carrier similar to Dillon 550.]​

So if you are using progressive press with full shellplate, differing resizing force can tilt/deflect shellplate to add varying input on bullet seating station to affect OAL variance. I have suggested and myth busted using pre-resized brass to eliminate this variable and many members reported using pre-resized brass reduced OAL variance - https://www.thehighroad.org/index.p...ect-on-oal-variance-progressive-press.833604/

Now if we were talking about case length or flare and crimp it would be another story.

Included in the OP with plans to do follow up (May turn into another myth busting thread)

• Sorting brass by resized case length could reduce OAL variance further

(I plan on doing some more OAL measurements with WIN headstamp brass with same/different resized case length)

As to taper crimp, since most case wall thickness at case mouth is around .011"+, I add .022" to the diameter of bullet to essentially return flare back flat on bullet and skosh more. So for .3555" sized bullet, .3555" + .011" + .011" = .3775"+ and using .378" taper crimp returns flare back flat on bullet - https://www.thehighroad.org/index.p...nd-bullet-setback.830072/page-3#post-10712225

It doesn't say, but I'm inferring that seating and crimping were separated during these tests?

I mentioned seating and taper crimping were done in the same step in the OP

• Bullets were seated and taper crimped in same step at Station #6

 

[Atavar]

If you are reloading on progressive press where case base is captured within the shellplate, effects of shellplate tilt/deflection can be a variable to affect OAL variance.

Then that is an issue with the press design and again the brass is not the culprit.

 

[LiveLife]

If you are reloading on progressive press where case base is captured within the shellplate, effects of shellplate tilt/deflection can be a variable to affect OAL variance.

Then that is an issue with the press design and again the brass is not the culprit.

Fair enough. I added "Progressive Press" to the thread title and OP.

BTW, OP listed data from Pro 6000/1000, both progressive presses.

 

[PO2Hammer]

Brass hardness or stiffness seems to have an effect on OAL.
CBC brass (stiff) will always load about .010” longer for me than Blazer brass (soft). Same bullet, same die settings…..
I think there is some spring back when bullets are seated in stiff brass.

 

[LiveLife]

Brass hardness or stiffness seems to have an effect on OAL.
CBC brass (stiff) will always load about .010” longer for me than Blazer brass (soft). Same bullet, same die settings…..
I think there is some spring back when bullets are seated in stiff brass.

I once picked up 50 shiny new PMC 45ACP once-fired brass from an indoor range.

When I got home, I loaded some to find the case neck collapsed (I didn't make any change to my die settings). After some head scratching, die adjustment and more collapsed case necks, I deemed the soft brass to be the root cause. I recycled the entire lot of 50 brass and never had another collapsed case neck issue.

Those cases definitely did not "spring back".

 

[PO2Hammer]

Hardly a test of hard vs soft 9mm brass.
Take 5 CBC cases and 5 Blazer cases and make up some dummy rounds with a quality bullet and see what results you get.

 

[LiveLife]

Hardly a test of hard vs soft 9mm brass.
Take 5 CBC cases and 5 Blazer cases and make up some dummy rounds with a quality bullet and see what results you get.

I do consider RMR 115 gr FMJ "quality bullet" used as reference 9mm bullet for all of my current testing/myth busting.

If it is good enough for ELEY match ammunition, it should be "quality"? (Yes, ELEY uses RMR "in-house" jacketed bullets) - https://www.eleyammunition.com/minor9_competition_pistol_pcc_rounds/

 

[9mmepiphany]

Then that is an issue with the press design and again the brass is not the culprit.

You could allege that, but it is how the different cases affect the press that cause the differences in OAL.

When cases are sorted, variances in OAL are reduced. This would lead one to believe that the "culprit" is indeed the case

 

[Atavar]

You could allege that, but it is how the different cases affect the press that cause the differences in OAL.

When cases are sorted, variances in OAL are reduced. This would lead one to believe that the "culprit" is indeed the case

Or a failure of the press to handle any minor variance

 

[lordpaxman]

It’s an interesting theory. While it may apply to a Lee progressive with you operating it, I don’t think it extends to every progressive press and process.

So using above sample of mixed range brass, total swing in OAL variance could be .007"

I’m not sure I understand your methodology. You ran a sample, I didn’t see the sample size, of unsorted headstamps, then curated and measured by headstamp and that’s what’s in the OP? I guess the “HS unsorted” bulleted list seems odd to me.
Were there the same number of headstamps? Was there a specific order in which those headstamps were in each station on the press?

I don’t dispute your findings, I’m just curious as to how it might relate to my process. The one thing I have seen in other threads is those who deprime/resize in one pass, and then load in the second pass say there’s more consistency in COLs for mixed HS, which relates to the resizing force and it’s affect on the other stations.

 

[LiveLife]

I’m not sure I understand your methodology.

My initial attempt at myth busting/confirming quickly got out of hand after 20+ topics with some disagreement on our findings and I decided to do one specific myth busting/confirming at a time using better methodology - https://www.thehighroad.org/index.p...usted-or-confirmed.579524/page-5#post-7219914

Now these myth busting threads follow the core principles of using objective, measurable, repeatable data to either bust or confirm long standing notions or misnotions where THR members can't seem to agree or disagree in unison. Current longstanding notion/misnotion that THR members can't agree/disagree on in unison is the topic of whether to trim or not trim straight walled semi-auto pistol cases that could be myth busted/confirmed next - https://www.thehighroad.org/index.php?threads/trimming-auto-pistol-cases-is-unnecessary-waste-of-time-so-that’s-what-i’m-doing.921544/#post-12682628

Myth busting threads stemmed from responses from THR members demanding objective testing with large enough sample size to verify one variable at a time.

My recent attempt to survey THR for myth busting topic threads didn't go too well as I was "fishing" for topics I could myth bust one specific variable at a time - https://www.thehighroad.org/index.p...oading-discussion.893537/page-4#post-12031011

So now I identify myth busting topics one at a time like this no concensus thread discussion on "sorting brass" that triggered myth busting or confirming - https://www.thehighroad.org/index.php?threads/sorting-brass.864175/#post-11404415

You ran a sample, I didn’t see the sample size ... I guess the “HS unsorted” bulleted list seems odd to me.

Sample #1 - (Six Pack Pro out of the box shellplate was found loose and test repeated with sample #2) Initial 20 sample R-P cases were selected for OAL variance test (10 cases around .750" and 10 cases .751"-.752") in turret mode (One case at a time) - https://www.thehighroad.org/index.p...ing-for-oal-consistency.911743/#post-12442742

OAL measurements for case lengths around .750":​

• 2 rounds measured 1.125"
• 6 rounds measured 1.126"
• 2 rounds measured 1.127"

OAL measurements for cases .751"-.752":​

• 1 round measured 1.125"
• 1 round measured 1.126"
• 8 rounds measured 1.127"

Sample #2 - (Shellplate tightened) 20 (40 total sample) R-P headstamp cases resized around .750" were selected in turret mode (One case at a time) - https://www.thehighroad.org/index.p...ing-for-oal-consistency.911743/#post-12443544

OAL measurements:​

• 14 rounds measured 1.125"
• 6 rounds measured 1.126"

Sample #3 - 10 (50 total sample) R-P headstamp cases resized around .750" were selected in turret mode (One case at a time) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-2#post-12444278

OAL measurements:​

• 1 round measured 1.124"
• 5 rounds measured 1.125"
• 4 rounds measured 1.126"

Sample #4 - 30 (80 total sample) mixed headstamp and "unsorted" by resized case length (Resized case length indicated before OAL) in progressive mode (Shellplate full) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-2#post-12444828

1. R-P .751" - 1.134"
2. WIN .749" - 1.134"
3. Blazer .747" - 1.129"
4. G.F.L. .748" - 1.131"
5. .FC. .750" - 1.129"
6. FC .750" - 1.128"
7. WIN .750" - 1.131"
8. G.F.L. .750" - 1.131"
9. Blazer .748" - 1.129"
10. WIN .749" - 1.130"
11. .FC. .747" - 1.128"
12. FC - .752" - 1.131"
13. G.F.L. .750" - 1.129"
14. WIN .750" - 1.134"
15. R-P .750" - 1.132"
16. Blazer .750" - 1.130"
17. WIN .748" - 1.132"
18. FC .750" - 1.130"
19. R-P .749" - 1.133"
20. G.F.L. .750" - 1.133"
21. WIN .749" - 1.133"
22. WIN .747" - 1.131"
23. WIN .750" - 1.132"
24. WIN .750" - 1.131"
25. WIN .751" - 1.133"
26. WIN .750" - 1.131"
27. WIN .748" - 1.132"
28. WIN .750" - 1.132"
29. WIN .747" - 1.133"
30. WIN .751" - 1.133"

Sample #5 - 20 (100 total sample) FC/.FC./Blazer "unsorted" by resized case length (Resized case length indicated before OAL) in progressive mode (Shellplate full) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-3#post-12446054

• FC .750" - 1.130"
• FC .749" - 1.130"
• FC .751" - 1.130"
• FC .750" - 1.132"
• FC .751" - 1.131"
• .FC. .749" - 1.128"
• .FC. .750" - 1.131"
• .FC. .750" - 1.130"
• .FC. .748" - 1.131"
• .FC. .751" - 1.131"
• Blazer .749" - 1.133"
• Blazer .752" - 1.129"
• Blazer .750" - 1.131"
• Blazer .749" - 1.133"
• Blazer .751" - 1.130"
• Blazer .748" - 1.132"
• Blazer .750" - 1.130"
• Blazer .749" - 1.128"
• Blazer .750" - 1.128"
• Blazer .748" - 1.130

Sample #6 - 15 (115 total sample) R-P/R-P "." brass "unsorted" by resized case length (Resized case length indicated before OAL) in progressive mode (Shellplate full) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-3#post-12446462

1. R-P .749" - 1.134"
2. R-P .748" - 1.134"
3. R-P .749" - 1.133"
4. R-P .750" - 1.133"
5. R-P .749" - 1.133"
6. R-P"." .750" - 1.134"
7. R-P"." .749" - 1.135"
8. R-P"." .750" - 1.134"
9. R-P"." .749" - 1.134"
10. R-P"." .750" - 1.134"
11. R-P"." .750" - 1.135"
12. R-P"." .749" - 1.134"
13. R-P"." .750" - 1.135"
14. R-P"." .749" - 1.135"
15. R-P"." .749" - 1.135"

Summary of "unsorted" (by resized length) mixed range brass Progressive Mode compilation of OAL consistency (shellplate full) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-3#post-12446468

I don’t dispute your findings, I’m just curious as to how it might relate to my process. The one thing I have seen in other threads is those who deprime/resize in one pass, and then load in the second pass say there’s more consistency in COLs for mixed HS, which relates to the resizing force and it’s affect on the other stations.

That myth busting to remove shellplate tilt/deflection variable by using pre-resized brass was done in the "Myth Busting Pre-Resized Brass Affect On OAL Variance - Progressive Press" thread - https://www.thehighroad.org/index.p...progressive-press.833604/page-2#post-10779806

It’s an interesting theory. While it may apply to a Lee progressive with you operating it, I don’t think it extends to every progressive press and process.

@9mmepiphany and other members using non-Lee progressive press have already confirmed using sorted headstamp brass - https://www.thehighroad.org/index.php?threads/using-matched-brass.908631/#post-12367246

I have used Dillon 650/550 but they got replaced by Lee SPP/Pro 6000 and 2023 Pro 1000 as finished OAL variance is quite tight (Down to .001" depending on headstamp, the focus of this myth busting thread) and I don't have to peck for individual primer anymore (Now, it's dump and shake to flip ... Much faster/easier).

 

[AJC1]

My initial attempt at myth busting/confirming quickly got out of hand after 20+ topics with some disagreement on our findings and I decided to do one specific myth busting/confirming at a time using better methodology - https://www.thehighroad.org/index.p...usted-or-confirmed.579524/page-5#post-7219914

Now these myth busting threads follow the core principles of using objective, measurable, repeatable data to either bust or confirm long standing notions or misnotions where THR members can't seem to agree or disagree in unison. Current longstanding notion/misnotion that THR members can't agree/disagree on in unison is the topic of whether to trim or not trim straight walled semi-auto pistol cases that could be myth busted/confirmed next - https://www.thehighroad.org/index.php?threads/trimming-auto-pistol-cases-is-unnecessary-waste-of-time-so-that’s-what-i’m-doing.921544/#post-12682628

Myth busting threads stemmed from responses from THR members demanding objective testing with large enough sample size to verify one variable at a time.

My recent attempt to survey THR for myth busting topic threads didn't go too well as I was "fishing" for topics I could myth bust one specific variable at a time - https://www.thehighroad.org/index.p...oading-discussion.893537/page-4#post-12031011

So now I identify myth busting topics one at a time like this no concensus thread discussion on "sorting brass" that triggered myth busting or confirming - https://www.thehighroad.org/index.php?threads/sorting-brass.864175/#post-11404415



Sample #1 - (Six Pack Pro out of the box shellplate was found loose and test repeated with sample #2) Initial 20 sample R-P cases were selected for OAL variance test (10 cases around .750" and 10 cases .751"-.752") in turret mode (One case at a time) - https://www.thehighroad.org/index.p...ing-for-oal-consistency.911743/#post-12442742

OAL measurements for case lengths around .750":​

• 2 rounds measured 1.125"
• 6 rounds measured 1.126"
• 2 rounds measured 1.127"

OAL measurements for cases .751"-.752":​

• 1 round measured 1.125"
• 1 round measured 1.126"
• 8 rounds measured 1.127"

Sample #2 - (Shellplate tightened) 20 (40 total sample) R-P headstamp cases resized around .750" were selected in turret mode (One case at a time) - https://www.thehighroad.org/index.p...ing-for-oal-consistency.911743/#post-12443544

OAL measurements:​

• 14 rounds measured 1.125"
• 6 rounds measured 1.126"

Sample #3 - 10 (50 total sample) R-P headstamp cases resized around .750" were selected in turret mode (One case at a time) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-2#post-12444278

OAL measurements:​

• 1 round measured 1.124"
• 5 rounds measured 1.125"
• 4 rounds measured 1.126"

Sample #4 - 30 (80 total sample) mixed headstamp and "unsorted" by resized case length (Resized case length indicated before OAL) in progressive mode (Shellplate full) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-2#post-12444828

1. R-P .751" - 1.134"
2. WIN .749" - 1.134"
3. Blazer .747" - 1.129"
4. G.F.L. .748" - 1.131"
5. .FC. .750" - 1.129"
6. FC .750" - 1.128"
7. WIN .750" - 1.131"
8. G.F.L. .750" - 1.131"
9. Blazer .748" - 1.129"
10. WIN .749" - 1.130"
11. .FC. .747" - 1.128"
12. FC - .752" - 1.131"
13. G.F.L. .750" - 1.129"
14. WIN .750" - 1.134"
15. R-P .750" - 1.132"
16. Blazer .750" - 1.130"
17. WIN .748" - 1.132"
18. FC .750" - 1.130"
19. R-P .749" - 1.133"
20. G.F.L. .750" - 1.133"
21. WIN .749" - 1.133"
22. WIN .747" - 1.131"
23. WIN .750" - 1.132"
24. WIN .750" - 1.131"
25. WIN .751" - 1.133"
26. WIN .750" - 1.131"
27. WIN .748" - 1.132"
28. WIN .750" - 1.132"
29. WIN .747" - 1.133"
30. WIN .751" - 1.133"

Sample #5 - 20 (100 total sample) FC/.FC./Blazer "unsorted" by resized case length (Resized case length indicated before OAL) in progressive mode (Shellplate full) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-3#post-12446054

• FC .750" - 1.130"
• FC .749" - 1.130"
• FC .751" - 1.130"
• FC .750" - 1.132"
• FC .751" - 1.131"
• .FC. .749" - 1.128"
• .FC. .750" - 1.131"
• .FC. .750" - 1.130"
• .FC. .748" - 1.131"
• .FC. .751" - 1.131"
• Blazer .749" - 1.133"
• Blazer .752" - 1.129"
• Blazer .750" - 1.131"
• Blazer .749" - 1.133"
• Blazer .751" - 1.130"
• Blazer .748" - 1.132"
• Blazer .750" - 1.130"
• Blazer .749" - 1.128"
• Blazer .750" - 1.128"
• Blazer .748" - 1.130

Sample #6 - 15 (115 total sample) R-P/R-P "." brass "unsorted" by resized case length (Resized case length indicated before OAL) in progressive mode (Shellplate full) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-3#post-12446462

1. R-P .749" - 1.134"
2. R-P .748" - 1.134"
3. R-P .749" - 1.133"
4. R-P .750" - 1.133"
5. R-P .749" - 1.133"
6. R-P"." .750" - 1.134"
7. R-P"." .749" - 1.135"
8. R-P"." .750" - 1.134"
9. R-P"." .749" - 1.134"
10. R-P"." .750" - 1.134"
11. R-P"." .750" - 1.135"
12. R-P"." .749" - 1.134"
13. R-P"." .750" - 1.135"
14. R-P"." .749" - 1.135"
15. R-P"." .749" - 1.135"

Summary of "unsorted" (by resized length) mixed range brass Progressive Mode compilation of OAL consistency (shellplate full) - https://www.thehighroad.org/index.p...r-oal-consistency.911743/page-3#post-12446468


That myth busting to remove shellplate tilt/deflection variable by using pre-resized brass was done in the "Myth Busting Pre-Resized Brass Affect On OAL Variance - Progressive Press" thread - https://www.thehighroad.org/index.p...progressive-press.833604/page-2#post-10779806


@9mmepiphany and other members using non-Lee progressive press have already confirmed using sorted headstamp brass - https://www.thehighroad.org/index.php?threads/using-matched-brass.908631/#post-12367246

I have used Dillon 650/550 but they got replaced by Lee SPP/Pro 6000 and 2023 Pro 1000 as finished OAL variance is quite tight (Down to .001" depending on headstamp, the focus of this myth busting thread) and I don't have to peck for individual primer anymore (Now, it's dump and shake to flip ... Much faster/easier).

I sure enjoy the mental game of reloading, but your definitely next level. The time you put into these tests/myths helps keep me motivated to find factual based answers vs conjecture.... thanks for your time/efforts.