Questions.. Loading Dies..Lee?? FCD??

[hobbit99]

I started a new thread here because I did not want this to get mixed up in my other "powder" thread. Completely different scenario here...

 

I just checked and I currently own 38 different die sets and multiple individual dies. I started loading in 1967.... When I started I bought whatever I could get reasonably that would do the job. Some of them are RCBS, a few are Lyman, and some others too. I even have one set of 30-06 dies made by Herters. After a few years I began wanting (coveting really..) the nicer dies that I could get from the Hollywood Gun Shop. I invested in Vickerman bullet seaters. I chose individual dies because I liked certain things about them. More recently, I have changed my purchase decisions to Redding dies almost exclusively (the last 15 years or so..) and I continue with that today. With ONE exception. When Lee came out with their Factory Crimp Die(s), I bought one to see if there was any value in crimping loads that normally would NOT be crimped. After some extensive experimentation, I was convinced that the idea behind a "factory crimp" was solid. All of my tested loads showed improvement with less variability... and some times MUCH less. The SDs were improved across the board. Based on that early testing, I have purchased additional Factory Crimp Dies for calibers that I load frequently. In addition to the improved SDs I have found no tendency for bullet setback even in high recoiling magnum rifle loads (such as .378 Weatherby and .458 Lott..). So, I am convinced that the Lee Factory Crimp Die does what it says it will do.... at least for me.

 

So.... I have noticed that several folks around here specifically denounce the use of FCDs. I get the impression that many of you dislike firmly crimping pistol rounds. Since I am now starting to load 9mm and HAD intended to use a FCD on them, I am asking once again to be enlightened. What SPECIFICALLY are the objections to the FCD?? Is this just a problem with that particular die or to all crimp dies?? I WILL use a separate crimp die, even in my 650, so the only question is, should I avoid the FCD for some reason... and WHY??

 

Thanks for the help.... You guys rock.!

[MemphisMechanic]

Aggressively crimping coated or lead bullets can result in your press undersizing them, and result in loss of accuracy.

 

Given that the "crimp" in 9mm has little to no effect on avoiding setback or the like, there is no benefit to a visible or heavy  crimp on a 9mm load. 

 

Straighten the walls or bend then inward .001 and call it good.

 

On the FCD: I like it. A lot. The FCD will resize the brass during the final reloading step, and when you do things like load a really long 147gr for a gun like a CZ/XD/M&P that requires very short ammo... oftentimes older brass will bulge outward in the process. (Much moreso than if you load longer.)

 

If used in a hamfisted fashion the FCD can correct this. If simply cranked down all the way, you're back to swaying bullets and crappy accuracy. Most guys who tried one and didn't like it ... don't know how to set it. You can run the center crimp adjustment all the way down then thread the die body inward to set your crimp, and you have a traditional crimp die. Or you can thread the body down more and more and get more of a sizing die effect.

 

They're very flexible dies and I find them valuable. I used to run a mix of premium dies in 9mm (Redding, etc) but find an ordinary Lee die set with an FCD at the end makes ammo that's just as consistent and accurate, and it's got noticeably fewer defects.

 

Edited July 10, 2017 by MemphisMechanic

[Sarge]

I'm one of those who just uses it as an easy to adjust crimp die but that's because I use a U-die in station one. No need to resize the case after that. 

  I also concur LEE dies are great dies at a great price.

  Edited to make the spelling police happy.

Edited July 10, 2017 by Sarge

[GrumpyOne]

10 minutes ago, Sarge said:

I'm one of those who just uses it as an easy to adjust crimp die but that's because I use a U-die in station one. No need to resize the case after that. But the FCD does work well in it's designed roll too.

  I also concur LEE dies are great dies at a great price.

 

Advise/Advice

 

roll

rōl/

verb

1. 1.

   move or cause to move in a particular direction by turning over and over on an axis.

   "the car rolled down into a ditch"

   synonyms:

   turn round and round, go round and round, turn over and over, spin, rotate "the bottle rolled down the table"
2. 2.

   (of a vehicle) move or run on wheels.

   "the van was rolling along the highway"

   synonyms:

   travel, go, move, pass, cruise, sweep "we rolled past fields"   role rōl/ noun an actor's part in a play, movie, etc. "Dietrich's role as a wife in war-torn Paris" synonyms: part; More   the function assumed or part played by a person or thing in a particular situation. "she greeted us all in her various roles of mother, friend, and daughter" synonyms: capacity, position, job, post, office, duty, responsibility, mantle, place;

[N3WWN]

I don't sort or reload by headstamp, but I do cull stepped 9mm brass before reloading.

 

Using the 9mm FCD with a Lee classic turret, I can tell when I've encountered brass that is thicker than normal because the FCD station requires a LOT more force to complete the stroke.  Those rounds go in the practice ammo can.  The rounds that go through the FCD with minimal effort go into the match ammo can prior to plunk testing before major matches.

 

This has resolved the biggest problem that I saw with over-crimping:  With my 9mm Single Stack gun, I was getting the occasional tumbling bullet with coated Acme 145gr RN-NLG bullets.  I've been using Acme bullets for a long time and am confident that it wasn't the bullets causing the problem.

 

What I attributed the tumbling bullets to was brass that was thicker than usual which resulted in the FCD functionally swaging the bullet with the case to the extent that the bullet could no longer engage the rifling properly.

 

I have not had an issue with tumbling bullets at a match after using the feedback from the FCD station to pull those rounds.

 

Not sure if this would work with a progressive press or not since all stations are used simultaneously.  

 

I use FCDs for all of the cartridges I reload, if available, for pistol, revolver and rifle.

 

My experience of reloading with an FCD is why I am positive that there is much less variation in 40 S&W brass than there is with 9mm brass.  

 

I don't encounter the "9mm excessive FCD force" issue with 40 brass and have loaded over 20-25k 40 S&W rounds and probably about 10k 9mm rounds in the last 3 years, all with coated lead projectiles (mostly Acme).

[hobbit99]

I think what I am hearing here parallels my own experience. Because bullet draw is largely dependent on neck tension, or case tension, depending.... a more uniform tension will definitely help with load performance. Variations in performance, particularly velocity variations, can be reduced significantly by crimping judiciously... as long as it is not overdone to the point of case deformation, bullet swaging, or reducing case necks to the point where loaded ammo will not headspace properly. When I first started I did not crimp anything I loaded until one day I noticed a bullet set back after firing a few rounds in a moderate recoil .350 Rem Mag. The rounds were loaded to fit in the magazine box of a carbine length Remington 600. They apparently took a nice bashing in the magazine and bullet setback was a reality. That caused me to go on a search where I discovered the FCD. Once I started chronographing my loads, I discovered just how much difference a uniform neck tension could make.

 

I AM  a little concerned about the differences in case wall thickness in a selection of unsorted brass. Definitely don't want to swage the bullets..... I will continue to watch carefully for differences and weigh and measure some cases. I think I will be able to figure it out..!!

[hobbit99]

7 hours ago, MemphisMechanic said:

Aggressively crimping coated or lead bullets can result in your press undersizing them, and result in loss of accuracy.

 

Given that the "crimp" in 9mm has little to no effect on avoiding setback or the like, there is no benefit to a visible or heavy  crimp on a 9mm load. 

 

Straighten the walls or bend then inward .001 and call it good.

 

On the FCD: I like it. A lot. The FCD will resize the brass during the final reloading step, and when you do things like load a really long 147gr for a gun like a CZ/XD/M&P that requires very short ammo... oftentimes older brass will bulge outward in the process. (Much moreso than if you load longer.)

 

If used in a hamfisted fashion the FCD can correct this. If simply cranked down all the way, you're back to swaying bullets and crappy accuracy. Most guys who tried one and didn't like it ... don't know how to set it. You can run the center crimp adjustment all the way down then thread the die body inward to set your crimp, and you have a traditional crimp die. Or you can thread the body down more and more and get more of a sizing die effect.

 

They're very flexible dies and I find them valuable. I used to run a mix of premium dies in 9mm (Redding, etc) but find an ordinary Lee die set with an FCD at the end makes ammo that's just as consistent and accurate, and it's got noticeably fewer defects.

 

 

Thanks for your help...  I agree that the 9mm probably does not have enough recoil to adversely affect setback (usually..!), unless the cases are sized too large or too small diameter bullets are loaded. As long as case walls are thick enough and cases are sized to the point where they will fit the chamber readily, everything should be okay.... Of course there is the issue of the tapered case....... In any event, sizing the case walls "straight" or "bend them inward .001" sounds like pretty good advice. 

 

I don't plan on loading overly long bullets (hmmm... I don't think.??), so the case bulging you mention around the base of the bullet shouldn't be an issue. I will definitely keep it in mind though. 

 

I've never used a SET of Lee dies. Not saying I won't at some point, just never had the reason to do so yet. However, like you, I really like the FCD. For that reason, I continue to use them. I don't have one for every caliber, but for the most often loaded ones or the ones that require the most accuracy, I always purchase one.

 

Thanks again..

[MemphisMechanic]

Case mouth tension is what holds semi-auto bullets in place in the case. The crimp doesn't serve that role. Load a round into a properly sized case and crimp until the walls are barely straight... and see how hard it is to make the Bullet budge.

 

Hint: I've loaded my match ammo like that for 10 years without a single issue.

 

Edited July 10, 2017 by MemphisMechanic

[hobbit99]

7 hours ago, Sarge said:

I'm one of those who just uses it as an easy to adjust crimp die but that's because I use a U-die in station one. No need to resize the case after that. 

  I also concur LEE dies are great dies at a great price.

  Edited to make the spelling police happy.

 

Thanks Sarge.... I have not considered using a U die. Maybe I should..... But for now at least, I will stick to my conventional sizer unless I have problems with bulged cases. Guess I will have to wait and see..!! 

 

Yeah, those spelling police are hard to get along with. 

 

3 hours ago, N3WWN said:

...Using the 9mm FCD with a Lee classic turret, I can tell when I've encountered brass that is thicker than normal because the FCD station requires a LOT more force to complete the stroke.  Those rounds go in the practice ammo can.  The rounds that go through the FCD with minimal effort go into the match ammo can prior to plunk testing before major matches.

 

This has resolved the biggest problem that I saw with over-crimping:  With my 9mm Single Stack gun, I was getting the occasional tumbling bullet with coated Acme 145gr RN-NLG bullets.  I've been using Acme bullets for a long time and am confident that it wasn't the bullets causing the problem.

 

What I attributed the tumbling bullets to was brass that was thicker than usual which resulted in the FCD functionally swaging the bullet with the case to the extent that the bullet could no longer engage the rifling properly.

 

I have not had an issue with tumbling bullets at a match after using the feedback from the FCD station to pull those rounds. Not sure if this would work with a progressive press or not since all stations are used simultaneously.  I use FCDs for all of the cartridges I reload, if available, for pistol, revolver and rifle.

 

My experience of reloading with an FCD is why I am positive that there is much less variation in 40 S&W brass than there is with 9mm brass.  I don't encounter the "9mm excessive FCD force" issue with 40 brass and have loaded over 20-25k 40 S&W rounds and probably about 10k 9mm rounds in the last 3 years, all with coated lead projectiles (mostly Acme).

 

Very interesting information.... I can't conceive that a FCD could swage a bullet far enough to make loose or no contact with rifling. It is my understanding that Acme's bullets are sized at .356 to begin with...?? Is that correct.?? That would mean that the die would have to swage the bullet a considerable amount to cause a really loose fit in the barrel. If groove diameter is a nominal .355 and SAMMI allows +/- .0005, then a barrel could conceivably be as large as .3555 if it is within spec. Standards seem to indicate that lands are .008-.009 smaller in diameter than grooves, which would be .0045 difference per side. Now, how much "grab" is needed to impart stability to a bullet is somewhat open to conjecture, but for a bullet to truly be loose in the barrel would require a LOT of swaging!! A .356 bullet would have to be swaged down to .348 or so....before it would refuse to engrave the rifling. Of course, this would cause a lot of gas blow-by and the resulting cutting and deformation to the bullet base would also affect stability. Swaging to a lesser degree could cause a somewhat looser fit to the bore, and some blow-by as well. This would also affect accuracy to some extent. Hmmm... I don't know, I guess your results speak for themselves...... I just find it sort of hard to understand how a bullet swaged even a couple of thousandths could cause cause tumbling..... Tres interressant...

 

I think your statement about .40 brass versus 9mm sounds plausible. LOTS of inexpensive (and CHEAP..!) 9mm ammunition out there. Its easy to see how 9mm brass could have a lot of variation.

 

Thanks for the information and the interesting commentary.!

[hobbit99]

32 minutes ago, MemphisMechanic said:

Case mouth tension is what holds semi-auto bullets in place in the case. The crimp doesn't serve that role. Load a round into a properly sized case and crimp until the walls are barely straight... and see how hard it is to make the Bullet budge.

 

Hint: I've loaded my match ammo like that for 10 years without a single issue.

 

 

Agreed.... I also know that neck tension is what holds rifle bullets in cases as well. I also know that neck tension is NOT enough to do so in every instance. A lot depends on the condition of the brass, if it has been annealed, neck thickness and uniformity, and depth of bullet in the case. In a lot of situations loads crafted in that manner will experience projectile movement before firing. Most of the time the bullet moves back, but I've had some bullets work their way out of the case... especially if they were loaded to a long COAL or if the brass was recently annealed and was soft around the neck and shoulder, or exceptionally thin after reaming.

 

Of course all of that has nothing to do with 9mm loads but the taper on the case does, unless you have a pistol (barrel..???) with a stepped chamber that allows for case walls that are basically parallel. In a "standard" tapered chamber there is little to hold that bullet in place except the outer edges of the case mouth. I realize that there is still substantial friction  there, but not nearly the same as a case with parallel sides. The 9mm is one of a few semi-auto calibers that utilize a tapered chamber (most guns...). Most calibers do not. Therefore it is understandable that most folks consider semi-autos to not require crimps (in the normal sense..) because they consider the case to be a straight wall and there is plenty of "draw" to hold the bullet in place. Of course all of this is moot if you use a SB die or a U die that sizes to a smaller diameter...

 

In any event, I know how the standard stuff works, but admittedly my knowledge of the 9mm is pretty sparse at this point. Thanks again for the comments and the help. I enjoy the learning process..

[MemphisMechanic]

A light, proper crimp wont hurt anything. For certain.

 

Most new reloaders take "crimp" literally and they go too far and encounter all kinds of feeding or accuracy issues.

 

Not knowing your experience level, I gave the usual advice.

Edited July 10, 2017 by MemphisMechanic

[hobbit99]

4 hours ago, MemphisMechanic said:

A light, proper crimp wont hurt anything. For certain.

 

Most new reloaders take "crimp" literally and they go too far and encounter all kinds of feeding or accuracy issues.

 

Not knowing your experience level, I gave the usual advice.

 

Thanks again.... It is obvious that you are very knowledgeable about the things of which you speak. I have learned a lot from reading what you have had to say and some others here as well. When I ask a question there is no "gotcha" involved. I truly don't know, or I wouldn't ask. So, thanks for all of the help. Really....

 

I know I will have more questions as I move forward here.

[Steve RA]

Sort your brass and just use one brand - removes a lot of variables.

[hobbit99]

9 hours ago, Steve RA said:

Sort your brass and just use one brand - removes a lot of variables.

 

Yes it does.... The problem is, at least for me right now, I don't have enough of any one kind. I ordered 5000 from Monmouth and there is tremendous disparity in those cases. At least ten different headstamps that I recognize and more that I have never seen before. I need the brass for practice mostly..... I can set aside enough of one brand for match use if necessary. I just don't want to have to adapt loads or continuously sort brass by headstamp before loading. I will work it out by judicious sorting and weighing. It looks like that will be my only choice, at least for now.

Edited July 11, 2017 by hobbit99
stupid self-correcting stuff...

[N3WWN]

20 hours ago, hobbit99 said:

Very interesting information.... I can't conceive that a FCD could swage a bullet far enough to make loose or no contact with rifling. It is my understanding that Acme's bullets are sized at .356 to begin with...?? Is that correct.?? That would mean that the die would have to swage the bullet a considerable amount to cause a really loose fit in the barrel. If groove diameter is a nominal .355 and SAMMI allows +/- .0005, then a barrel could conceivably be as large as .3555 if it is within spec. Standards seem to indicate that lands are .008-.009 smaller in diameter than grooves, which would be .0045 difference per side. Now, how much "grab" is needed to impart stability to a bullet is somewhat open to conjecture, but for a bullet to truly be loose in the barrel would require a LOT of swaging!! A .356 bullet would have to be swaged down to .348 or so....before it would refuse to engrave the rifling. Of course, this would cause a lot of gas blow-by and the resulting cutting and deformation to the bullet base would also affect stability. Swaging to a lesser degree could cause a somewhat looser fit to the bore, and some blow-by as well. This would also affect accuracy to some extent. Hmmm... I don't know, I guess your results speak for themselves...... I just find it sort of hard to understand how a bullet swaged even a couple of thousandths could cause cause tumbling..... Tres interressant...

 

I think your statement about .40 brass versus 9mm sounds plausible. LOTS of inexpensive (and CHEAP..!) 9mm ammunition out there. Its easy to see how 9mm brass could have a lot of variation.

 

Thanks for the information and the interesting commentary.!

 

My micrometer is telling me that the Acme 145gr RN-NLG bullets are a consistent 0.3565".

 

Measuring some of the "good" range brass that I have prepped to load shows about 0.009"-0.011" for the top ~1/4" of the wall.

 

In contrast, the brass that I have culled out has walls the measure 0.013"-0.015", with 0.0135" being the most common (same top ~1/4" of the wall).  Not all of the brass requires a lot of force and I don't know which headstamp is more likely to require lots of force off the top of my head.  The ones that require more force may be even larger, but I don't know for sure.

 

These were small samples of 5 randomly selected bullets and cases out of each bin.

 

If I have the FCD set to just remove the flare from my "good" range brass, let's call that 0.010" for each wall + 0.3565" for the bullet, or 0.3585" at the case mouth.  If we throw in the worst case reject brass, that's 0.015" for each wall + 0.3565" for the bullet, or 0.3595"... BUT, the FCD is set to 0.3585", so the bullet is getting swaged 0.0010", resulting in a 0.3555" bullet at the case mouth.

 

Keep in mind that 9mm brass has tapered walls, too.  I don't know how fast the walls thicken and don't have a tubing micrometer that can measure deep inside a case, but I do know that some headstamps get thicker faster than others.  To swage the bullet to 0.348" at the base would only take the wall thickness increasing 0.00325".  That seems reasonable and would really decrease the bearing surface of the bullet that is engaging the rifling.

 

I'm pretty much just thinking out loud here...   My measurements could be wrong or the really shiny circumference around the case exactly as far as the bullet is inserted into the case may be due to something else.   (I tumble in crushed walnut shells which leaves a dull matte finish so the shiny ring stands out)

[MemphisMechanic]

I don't know anyone who shoots one brand of brass at locals or in practice. 

 

I cull stepped cases and crimped foreign headstamps. The rest gets loaded and shot. This is what the vast majority of USPSA shooters do.

 

It'll shoot a 1.5-2" group at 25yd through my Tanfoglio. That's good enough for me unless I'm headed to an Area match or Nationals.

 

Analogy alert:

 

Some guys like crafting the perfect beer. Most of us think it's more fun to drink.  When the former guy pops up online in the ammo topics, don't feel guilty for being the latter.

 

Edited July 11, 2017 by MemphisMechanic

[hobbit99]

I am going to take the option here of responding "in line" instead of quoting and restating.....

1 hour ago, N3WWN said:

 

My micrometer is telling me that the Acme 145gr RN-NLG bullets are a consistent 0.3565".  Okay...if you say so. I haven't measured. Acme quotes .356 on their site.... Even if you are correct, that means that Acme's bullets are a full thousandth (.001) larger than groove diameter at a minimum. And could be more depending on which side of nominal your barrel sits.

 

Measuring some of the "good" range brass that I have prepped to load shows about 0.009"-0.011" for the top ~1/4" of the wall. 

 

In contrast, the brass that I have culled out has walls the measure 0.013"-0.015", with 0.0135" being the most common (same top ~1/4" of the wall).  Not all of the brass requires a lot of force and I don't know which headstamp is more likely to require lots of force off the top of my head.  The ones that require more force may be even larger, but I don't know for sure. So your "culled" brass is about .003 +/- thicker at the case mouth... assuming your wall thickness measurement is correct. (Tough to do without a ball-end mic..). Good job if you have one....

 

These were small samples of 5 randomly selected bullets and cases out of each bin.

 

If I have the FCD set to just remove the flare from my "good" range brass, let's call that 0.010" for each wall + 0.3565" for the bullet, or 0.3585" at the case mouth.  If we throw in the worst case reject brass, that's 0.015" for each wall + 0.3565" for the bullet, or 0.3595"... BUT, the FCD is set to 0.3585", so the bullet is getting swaged 0.0010", resulting in a 0.3555" bullet at the case mouth. Okay, sounds correct so far.... That means the total amount of "swaging" that occurs is around one thousandth.. (.001)... AND the resulting bullet is still larger than the nominal groove diameter of the barrel in most cases.

 

Keep in mind that 9mm brass has tapered walls, too. Correct, but just because the form factor of the case tapers, it doesn't mean that the wall thickness tapers. (I don't know... I haven't sectioned a case ... or measured one).   I don't know how fast the walls thicken and don't have a tubing micrometer that can measure deep inside a case, but I do know that some headstamps get thicker faster than others.  To swage the bullet to 0.348" at the base would only take the wall thickness increasing 0.00325".  That seems reasonable and would really decrease the bearing surface of the bullet that is engaging the rifling. Actually, the increase would be .00375..... Using your numbers with an as crimped diameter of .3555 being further reduced to .348 means a further reduction of .0075.   .0075/2 = .00375 thickness increase in the case wall at the base of the bullet. Now using your original measurement for wall thickness at .010 at the mouth, that would mean that the case would have to thicken by approx 3.7X within a very short distance (bullet seating depth..)..... Now like I said, I haven't sectioned a case, but that seems to be a ridiculous amount of wall thickness increase.

 

I'm pretty much just thinking out loud here...   My measurements could be wrong or the really shiny circumference around the case exactly as far as the bullet is inserted into the case may be due to something else.   (I tumble in crushed walnut shells which leaves a dull matte finish so the shiny ring stands out). I suspect that the mark on the cases IS due to the bullet, just as you say. I'm just not sold that the amount of swaging that is occurring is sufficient to cause the effect you mention. Of course, there are a lot of unknowns here.   i.e.  The actual groove diameter of your barrel; The heat and pressure of the load used; How much obturation occurred; Was the bullet base damaged??;  High pressure causing the bullet to "strip" the rifling?;  AND, of course there is always the possibility that you are correct and the bullet was squashed to the point that gas blow-by caused it to upset upon leaving the muzzle....Tumble..?? Hard to imagine, but anecdotally you know what happened and what you did to affect a cure. 

 

And really, it doesn't matter. If a bullet tumbles, the load needs to be fixed. Why and How is a matter of logistics.....

 

[GrumpyOne]

On 7/10/2017 at 9:57 AM, Sarge said:

I'm one of those who just uses it as an easy to adjust crimp die but that's because I use a U-die in station one. No need to resize the case after that. 

  I also concur LEE dies are great dies at a great price.

  Edited to make the spelling police happy.

[hobbit99]

2 hours ago, MemphisMechanic said:

I don't know anyone who shoots one brand of brass at locals or in practice. 

 

I cull stepped cases and crimped foreign headstamps. The rest gets loaded and shot. This is what the vast majority of USPSA shooters do.

 

It'll shoot a 1.5-2" group at 25yd through my Tanfoglio. That's good enough for me unless I'm headed to an Area match or Nationals.

 

Analogy alert:

 

Some guys like crafting the perfect beer. Most of us think it's more fun to drink.  When the former guy pops up online in the ammo topics, don't feel guilty for being the latter.

 

 

You silver tongued devil.... Certainly have a way with words.!! 

 

The only cases I have culled at this point are the stepped ones I have reserved for the recycler. Everything else is still in play. There are a certain number of cases that I don't recognize and a few with sealed primers that are "suspect". Those are the ones that will be looked at more carefully. Originally, I was asking about the FCD because of some threads in the reloading forum and some statements there bashing it without explanation. Just hoping to find out more about the "why" of it all. In any event, I will continue to research here... maybe it will become more transparent. 

 

Re: Your "Analogy Alert" .....  I realize that I fit into that scenario somewhere. Of course, perceptions are strange things. My anal-retentive mode has served me well in various situations where attention to detail was first and foremost. I still make mistakes, but not because I haven't thought it through.... or because I just threw up my hands and said "that's good enough". One of my catch phrases that seems to properly state my position is:  "Why is there never enough time to do a job right, but always enough time to do a job over.??" 

 

I don't feel guilty for being the former OR the latter. Sometimes you're the butter and sometimes you're the knife..... to put a slightly "nicer" slant to a trite saying.!! 

[MemphisMechanic]

Well we all start out pretty cautious when asembing our own explosive devices (loading ammo is basically that) if we're smart about it.

 

Over time my personal desire to spend the absolute minimum amount of time in front of a press and as much time as possible shooting matches with it has led me to realize which details matter, and which horrific tolerances are actually just fine when it comes to "it shoots safe & groups well, just run it" specifications.

 

Again, some guys enjoy crafting ammo and take deep satisfaction from it. For me, it's just a necessary evil.

Edited July 11, 2017 by MemphisMechanic

[GrumpyOne]

12 minutes ago, MemphisMechanic said:

Well we all start out pretty cautious when asembing our own explosive devices (loading ammo is basically that) if we're smart about it.

 

Over time my personal desire to spend the absolute minimum amount of time in front of a press and as much time as possible shooting matches with it has led me to realize which details matter, and which horrific tolerances are actually just fine when it comes to "it shoots safe & groups well, just run it" specifications.

 

Again, some guys enjoy crafting ammo and take deep satisfaction from it. For me, it's just a necessary evil.

Yep. Caution is a good thing when you start, and caution is a good thing after 100k rounds reloaded...but at 100k rounds reloaded, you know better what to be cautious about. Sometimes, even after 100k rounds, that which you are no longer cautious about will rear it's ugly head, but it is rare. 

[tanks]

I crimp just enough to straighten out the bell to pass the case gauge.

[hobbit99]

I want to thank those who have contributed to this discussion. It has been enlightening. I find it a little amusing that almost everyone who has posted here in this discussion admits to the usefulness of the FCD. That seems to support my original thesis on the matter, even though there are some individuals posting on the reloading forum who seem to adhere to the idea that the FCD is totally worthless and is in fact a danger to the sport and to society as a whole. 

 

In any event, due to the absence of any reasoned response to the contrary, I guess I will just continue to use the FCD (very carefully..!) as a separate operation. When I have some reliable data from loads I will post it. Perhaps it will point to something definitive... or maybe not. Ultimately my goal is to produce 9mm ammunition that is solid, runs clean and cool, and performs better than I can shoot. And, much as MemphisMech has indicated, that is quite enough. There is no reason to spend hours and days and weeks testing and evaluating if there is nothing to be gained on the target. I just want to know that when I experience a sub-standard performance, the problem is with me.... not the ammunition.

 

[hobbit99]

8 hours ago, GrumpyOne said:

Yep. Caution is a good thing when you start, and caution is a good thing after 100k rounds reloaded...but at 100k rounds reloaded, you know better what to be cautious about. Sometimes, even after 100k rounds, that which you are no longer cautious about will rear it's ugly head, but it is rare. 

 

Spoken like someone who has seen the light.     Much as Falstaff proclaimed in one of The Bard's works.... "Discretion is the better part of valor." .... (probably misquoted, but I don't care.... the gist is correct.).... See Act I, Henry the Fourth.... 

 

[N3WWN]

 

On 7/11/2017 at 5:59 PM, hobbit99 said:

I am going to take the option here of responding "in line" instead of quoting and restating.....

 

Keep in mind that 9mm brass has tapered walls, too. Correct, but just because the form factor of the case tapers, it doesn't mean that the wall thickness tapers. (I don't know... I haven't sectioned a case ... or measured one).   I don't know how fast the walls thicken and don't have a tubing micrometer that can measure deep inside a case, but I do know that some headstamps get thicker faster than others.  To swage the bullet to 0.348" at the base would only take the wall thickness increasing 0.00325".  That seems reasonable and would really decrease the bearing surface of the bullet that is engaging the rifling. Actually, the increase would be .00375..... Using your numbers with an as crimped diameter of .3555 being further reduced to .348 means a further reduction of .0075.   .0075/2 = .00375 thickness increase in the case wall at the base of the bullet. Now using your original measurement for wall thickness at .010 at the mouth, that would mean that the case would have to thicken by approx 3.7X within a very short distance (bullet seating depth..)..... Now like I said, I haven't sectioned a case, but that seems to be a ridiculous amount of wall thickness increase.

 

Sorry for the bad math... 

 

Attached is an image (from another forum about sizing dies, so ignore the measurements) which shows the tapering of the walls themselves.  A Google image search for '9mm case wall thickness' returns some other examples of varying value.

 

I seat the Acme 145gr RN-NLG bullets to 1.102", so it's a fairly short COAL, but that's what I had to do to get it to work in all of our 9mm firearms.  The tapered wall thickness means the bullet meets more and more case thickness until the base of the bullet.  My short COAL exacerbates the issue.

 

I don't know if the thickness increases by 3.7x or not, but it doesn't seem unreasonable from this image.

 

I wasn't ever able to reclaim a tumbled bullet, so I can't do any root cause analysis... wish I could have, though!  

 

But, as you said, "...it doesn't matter. If a bullet tumbles, the load needs to be fixed."   For me, culling stepped brass all together and rejecting rounds that require excessive FCD force into the practice ammo bin resolved the tumbling bullets at matches.  I couldn't have done that without feedback from the FCD.