Lee Factory Crimp vs. Redding Profile die?

[Doughty]

Interesting stuff here.

I have a little observed information that might shed a little light or confusion on this.

Several years back, a friend who was an accomplished bench rest rifle shooter, conducted a little experiment. He had a good supply of brass in .308 Win and .223 Rem which had been match prepped. However, when chambering loaded rounds he was getting inconsistent results. Using an RCBS case mic he determined that the shoulders on the cases were not being sized to consistent lengths using the Hornaday dies that he had, in both calibers.

He therefore got another set of Hornaday dies for each caliber and tried again. Same results. Not sizing to consistent lenghts. He then tried running the brass into the dies multiple times (up to 4) and rotating the brass. This was somewhat better, but still out of spec and inconsistent.

He then got two sets each of RCBS dies and tried again. He now discovered that sometimes the brass would size to spec and consistent, but occasionally he had to run them through a second time.

Still not satisfied he got two sets each of Lee dies and ran his test. He found that he could run his brass through one time and they would size consistently and to spec.

How I found out about his test was he ask me to bring some of my mixed brass and much older RCBS dies over for a little test. I ran my brass through his sets of dies and got the same results he had. When running our collective brass through my dies, it was a little better than his RCBS dies, but not as good as the Lee dies.
He told me later that he tried this with a few other guys that he knew and got basically the same results, although most of the dies he was able to test were RCBS, quite a few Lees and only a few Hornadays.

I realize that this is still a relatively small amount of tests and does not deal exactly with the subject of case diameter but rather with (dare I say it) "headspace."
What his test said to me was that the Lee dies were pushing the brass past the point of "elasticity" for the brass tested, the RCBS dies were very near the point of elasticity, and that the Hornaday dies did not reach that point.

I still use my old RCBS dies and have not conducted any recent tests, but when I buy new dies now they're Lee's.

[1bluehorse]

"Well, guess that Chinaman's been runnin them cheap shells on me again.."

[1bluehorse]

[QUOTE=W.R.Buchanan;1714868]Son let me tell you something, and you really need to get your head around this. Either your measuring tools suck or your measuring technique sucks.

thats probably it, thanks. I know you weren't referring to me but thanks anyhow..

[W.R.Buchanan]

Doughty: It would seem that the Lee dies were sizing the cases a bit smaller and as a result they would chamber up in the rifle mentioned. RCBS now makes "Small Base dies" for .223 and .308 that size the cases about .001-.002 smaller in dia at the base than their regular sizing dies. This is supposedly to facilitate them chambering in Automatic rifles easier.

I was told buy an RCBS factory rep at the SHOT Show that the shop tolerances for the two series of dies actually overlap! In other words it is possible to get a set of small base dies that are actually bigger than a regular set of dies, and vice versa! Makes you wonder?

Every outfit has a different idea of what the tolerances of Die Manufacturing is, but they generally stay within the SAMMI specifications for factory produced ammo. Chambers on rounds like .30-06 and .308 have a .010 window so there is lot of leeway on how long the sized brass needs to be to go in most chambers. Obvoiously a match chamber is going to be made to tighter tolerances, but most people who shoot that type of gun are reloading cases that have been fired in that chamber and then only neck size.

Where you start to see real problems is when you get into wildcats where there is no SAMMI standard for each round.

We had a good discussion in the Special Projects forum here about the .40-06 AKA .400 Whelan. People had problems with this round functioning correctly starting sometime in the 60's or 70's. They had deviated from the correct shape of the case.

Someone posted an article from Petrov who actually researched this cartridge to the end and found that somewhere along the way they stopped blowing the case shoulder dia out larger so as a result the newer style cases only had a shoulder that was .020 on a side, or nearly the same size as an 06 case. Petrov went back to the source "T Whelan", and found the original drawings for the cartridge and found the descrepancy. There is nothing wrong with the .400 Whelan/.40-06 as long as you make it like it was intended. It's only the mutated version that has problems. REALLY?

The purpose of this description of the .400 Whelan's problems is to illustrate how easily source information gets mutated. This particular mutation even got spread so far that a major reference book (named on that thread) shows the .400 Whelan case nearly strait in shape. So now we have a major reference with errant infromation that is essentially "carved in stone."

My main reason for spending so much time on this thread is to squelch a myth which is gaining traction among those who don't understand how brass works.

Does a case mouth spring back when it comes from the die,,, Sure it does.

BUT THE AMOUNT IT SPRINGS BACK IS SO SMALL THAT IT DOESN'T MATTER IN THE REAL WORLD.

Let me define how small it is,,, .0001-.0003 on a .44 sized case,,, and only then on brass that is starting to get older. Since you can't measure to ten thousandths of an inch accurately with a set of Chinese dial calipers 99.9 % of reloaders will never see this, and ones who think they do need to go back and measure again with something a little more up to the task.

I was told earlier that you don't need fancy measuring tools to see this springback thing you just need "Common Sense."

Well ya kinda do need fancy tools to measure this close, or at least need to know how to operate the ones you have to their full potential.

AS far as the "Common Sense" part goes. We have idiots who are proposing Common Sense Gun Laws all over this country all the time. I always have to ask "who's 'common sense' they are referring to?" As the ones talking have never shown any that I have seen.

The liberal mindset is a dangerous thing and it gains traction in a society by slowly chipping away at the basic rules and source data of that society's existance. This effectively "Dumbs Down" the population. New studies come along all the time to refute the original correct data on a given subject and are accepted as fact even thought the data maybe flawed. Look at all the BS and corrupted data they put forth to sell Global warming, and for no other raeason than to make money off of it! Very sad day for the scientific community.

Now, the Constitution is a 'living breathing document" that you can change at any time, to say what ever you want it to, because most people have never been taught how to use a dictionary, or you just simply beileve what someone says the words mean, because it is easier than finding out for yourself!

This is the basis of stupidity!

Look where we are at right now? and if you really want to see where the rest of our country is going just look here in CA. This is a perfect example of what happens when you convince people to accept lies and false data as the truth.

I hate this more than just about anything I can think of, because it is convincing people to believe in a LIE! in California they have convinced about 60% of the people. That's a pretty serious up hill battle for the losing side to overcome. Alot of those people are supposed to be pretty smart but they swallow just like the peons new here from down south. Just because you have a PHD in BFD doesn't mean you know how to tie your shoes, Einstein didn't!

See my signature on every post I do. That's what it means!

Don't let it happen where you live. If you want to see just how bad it could get, watch the movie "Idiocracy" it is a good depiction of what would happen if completely stupid people ran the country. Only problem we have,,, is the people behind the stupid people are the ones who want to put the chains on you, and they are NOT stupid.

It all starts with accepting false data as the truth. Guys you always need to do your homework.

If I can do anything to stop it in one small area of my life believe me I surely will!

Randy

[nanuk]

How about them Oakland Raiders!!!

[Char-Gar]

"I am not a science type and hold no credentials that would enable me to speak to the "spring back vs. no spring back" issue, but I do know a few things about handloading.

If you have a sizing die that is made to proper specs and an expanding plug that is correct for the bullet diameter, spring back, if such exists, is of no consequence. You will run accross the occasional lot of out of spec brass, but that is not common.

This board, and others like it, are a continuing source of amazement to me. Folks keep coming up with issues and theories that have never been a concern to handloaders before now. You would think that somebody would have discovered these things years ago. Folks have too much time on their hands, that would be better spend on the shooting range, where theory doesn't mean much. There, it is all about the hole in the target."

This was my take on the Great Spring Back Argument of 2012", and I have no changed my mind. As Shakespear would have said, Spring Back is Much Ado About Nothing.

[LUBEDUDE]

Yes you are right - Spring back is much ado about nothing.

And Mr Buchanan could have ignored the whole issue and packed up his guns and gone to the range for a good time.

Instead he decided to uphold the high standards of this forum and integrity by stopping misinformation with proof and going to great lengths with tenacity in offering his help and equipment.

He could have have gotten mad and let things slide and then this would be just like any other forum on the net.

My hat is off to Mr Buchanan for his utmost patience, knowledge, offerings, and contributions which make this forum unique.

[1hole]

Goodness, the misunderstandings over the simple task of crimping a hand gun cartridge are massive, ditto what a Redding "Profile" and Lee "Factory Crimp Die" will accomplish. Each reloader should buy what he wants but he should know what he's talking about when recommending crimpers.

The Profile Crimp Die allows for a slighly heavier than "normal" roll crimp. Whether or not that's helpful for a specific use is up to the user to determine for himself.

The FCD also applies an excellant crimp. It does NOT automatically change anything and will not change anything UNLESS the loaded round exceeds normal max SAAMI diameter. The purpose of the FCD "post seating sizer ring" is to insure that every round WILL chamber without jamming in any firearm ever chambered for that caliber and do it every time. Whether or not that is useful is up to the user to determine for himself.

The elastic limts of case brass is only a thou or so; springback after both firing AND sizing is limited to that. Ditto actual "neck/bullet tension".

[1bluehorse]

Yes you are right - Spring back is much ado about nothing.


Instead he decided to uphold the high standards of this forum and integrity by stopping misinformation with proof and going to great lengths with tenacity in offering his help and equipment.

My hat is off to Mr Buchanan for his utmost patience, knowledge, offerings, and contributions which make this forum unique.

Glad he proved it to you because he sure didn't to me. I did the exact same measurements with 45 colt brass (RP, Starline, and Winchester) and entered my results here. ( I guess my credentials are suspect ) The results came out different from Mr Buchanan's. Go check it out yourself, I'm sure you have a set of calipers..but like some of the others here I could really care less if it does or not..but please don't question my integrity and the posting of misinformation. .

[hylander]

Glad he proved it to you because he sure didn't to me. I did the exact same measurements with 45 colt brass (RP, Starline, and Winchester) and entered my results here. ( I guess my credentials are suspect ) The results came out different from Mr Buchanan's. Go check it out yourself, I'm sure you have a set of calipers..but like some of the others here I could really care less if it does or not..but please don't question my integrity and the posting of misinformation. .

I to posted my measurements but was told I must not know what I'm doing or my tools are junk. I have since measured more brass and different calibers and used different calipers, measuring just as Mr. W.R.Buchanan has in his photos.
I still come up with .002 - .003 springback if you want to call it that.
Anywho no since in getting the tail feathers in a bunch, because we are to far apart to compair findings side by side and we are just not going to agree.

[LUBEDUDE]

At the very begining of this post I PM'd Mr Buchanan about questions pertaining to the oringial post so not to come across as confrontational.

He suggested that I take some measurements 1bluehorse. I did to my satisfaction.

I just did again and took some pics for you, I hope to your satisfaction.

Measurement of the ID of the 357 sizing die is .373 .

Measurement of the case after coming out of the die is .373 . ( i waited a good 5 or 6 minutes in case you guys said it would take a while for it to spring back)






I guess my $30-$40 cheapo electronic calipers that in reality are probably $9.00 china junk ones did all right.

[1bluehorse]

What a conundrum....we have some that have measured and found naught..we have others that have measured and found a difference.. while it probably makes not a bit of difference one way or the other at least it has finally become "interesting" simply out of curiosity....

[W.R.Buchanan]

Here's the deal guys and "bluehorse" mentioned it above.. If we could all get together at once and measure each others stuff we could find where the discrepancys lie.

With calipers. You must hold consistant thumb pressure on the the movable jaw while rotating the case in the center of the jaws. This technique will show any inconsistancies in roundness of the measured piece.

Another place discrepancy could show up is in the difference of the mechanical calibration of the inside and outside measuring surfaces of the calipers. Obviously if they both aren't saying the same thing then something is wrong.

When you zero the calipers, be they electronic or mechanical you need to wipe the jaw surfaces with you finger or thumb. This will remove any thing that might have stuck to the jaws and all it takes to be off is a dust particle to be .001 off. Then you zero either the dial or the readout on your tool. At that point the "outside jaws" are zeroed or calibrated the best that you can do without more precise instrumentation. Good enough for this test.

Now at this point the inside jaws should be zeroed too unless they are physically out of calibration with the outside jaws. This would require them being sent to a Meterology lab for calibration where they would physically lap the 4 surfaces until they read ZERO.

Since nobody has the equipment at home or in their shop to do this, the next best thing is to measure a known ID and compare it to what the calipers say. A ring gauge would be a good tool to use or a bored hole around .500 that could be verified but using telescoping gages and a micrometer.

When taking an ID measurement you MUST continuously hold outward tension on the jaws, and rotate the part on the jaws to insure that you are in fact getting a true reading . The jaws MUST be exactly square to the work or you will get a bogus reading. Generally the highest ID reading you get as you are rotating the part is the actual size of the hole as read by THAT tool.

THIS IS NOT THAT EASY TO DO AND REQUIRES PRACTICE.

AS long as your ID and OD jaws read the same or zero exactly the same then you probably are pretty close. Just because the tool is new or expensive does not mean it is accurate. All measuring tools must be verified before they are used, and checked frequently.

IF you your ID jaws are .001 off when your OD jaws are zeroed you will have a discrepancy of .001 when you measure a hole.

Jaw flex: When you measure enough parts with the same tool, you get a feel for how much pressure to put of the jaws when reading the dial. You will notice that you can make the dial move a few thou just by increasing or decreasing the pressure on the part. This is caused by jaw flex and the more the tool has been used to bigger problem it can become.

There is an adjustment "gib" on most calipers with two small screws that you can take up the slack with. You tighten the gib untill it locks the jaw and then back the screws off until you can move the jaw with out too much resistance. You can test this by measuring a pin or something and flexing the jaws but changing the pressure. IF the jaws close up more than .001-2 then you need to adjust the gib to tighten the calipers up.

Also it kind of makes a difference where in the jaws you take the measurement. Obviously the further out you are the smaller the reading will be given the same amount of pressure on the jaw. IE the jaws flex. The approximate center is the best place.

Consistancy in the amount of pressure you use is the key to getting accurate measuremnents from Dial or Electronic calipers.

On ID measurements it is the most difficult thing to control and does require some practice to achieve credible results. If the jaws are cocked in any direction slightly you will NOT get a valid reading. There are three directions they can be cocked with relation to the cenetrline of the hole you are measuring. They all have to be lined up at once!

Even then you need to take the same measurement several times to insure that, that measurement repeats. Doing it only once is a recipe for failure. Obviously if the measurement doesn't repeat you haven't got a valid test. Time to figure out what you are doing wrong and correct it.

One last point. Your inexpensive tool may or may not deliver perfectly consistant accurate readings, however if you learn to calibrate them, and learn how to get good consistant readings then you will be close enough for any of this reloading stuff.

The amount of error in a set of mechanical calipers is in the rack and pinion that drives the dial. If the jaws are closed and the dial reads zero then the tool is calibrated with in the amount of error made into the rack. It may Zero per inch, it may be .001 per inch or even more. However from Zero to 1 inch the amount of mechanical error will probably be negligable. If you have .001 per inch then you would have .006 at 6" so you see how that works. This is also why you would measure things of known size in 1 inch increments just so you knew how bad your error will be when you get out to the end of travel.

The 2 sets Of Mitutoyo Calipers I use most often are 1-12" One is off .001 in 12" the other is .000 in 12" becasue it is virtually new and I keep it that way as a reference tool to check the others.

The key to the whole show is knowing how to take consistant readings. You can allow for calibration issues if you know they exist and know which direction they affect your readings.

You cannot compensate for inconsistant readings, simply because you never know which one is the right answer! It's like the man with two clocks, he never knwos what time it really is.

When I took my original measurements on my .44 cases and die I used 3 sets of fairly expensive calipers. All of which I know to be accurate because I use them everyday, and check them against standards frequently. This is how I verified my readings were correct.

If I am boring a hole in a piece of Titanium that is worth $500, and I don't get and accurate measurement on a hole diameter, and then I remove too much material on the fianl pass and scrap the part,,, It has a significant impact on my business. If I do it to 50 parts based on a wrong measurement I am out of business! I would also be classified as "completely stupid" for not checking my parts frequently everystep of the way. In my business you have to check check check, or you get burned.

In reloading it is doubtful you will go out of business, but you could have a problem you don't want. So learning the techniques I discussed above will benefit not only at the reloading bench and range, but on anything else you chose to measure with these tools. My tools get used for reloading about 2% of the time, the rest of the time is all about money.

I hope some of this helps with the understanding of using these tools. My only intention here is to educate and promote understanding and make everyone better in the end. My sometimes curt demeanor, not withstanding.

I am always availalbe to answer questions, and will always do so to my best ability.

Randy

[LUBEDUDE]

I used the same measuring techniques as stated above to get my identical results.

They were taught to me 40+ years ago in 8th grade metal shop by Mr. Mershon. Glad to see something correct was taught to me in public school and actually stuck.

[GT1]

I opened this thread expecting a die argument in the end, but it was well worthwhile and has cleared something up(in my mind, anyway) that was hard to understand from what I had read across various forums.

Thanks for the well written posts, W.R.Buchanan. It is nice to have something explained thoroughly from someone well versed in hands-on machining.

Now I need to go practice my measuring technique.

[Colorado4wheel]

You don't need dial calipers to confirm brass has spring back. Your lost in your world of measuring and can't see the forest for the trees. If you can't easily push the brass back in the sizing die then that proves brass has spring back. It's as simple as that. I am posting a video here shortly. With expensive dial calipers. At my machinist friends shop. But none of that matters really. Just do this. Size a case. Try and put it back in the sizer by hand. It will go in part way as it compresses the first part of the case that is thin and easy to move. After it goes in part way (and it is being compressed) it will not go in any farther easily because the brass has sprung back larger then the sizing die. Video to come shortly.

[Colorado4wheel]

All metals will "spring back" when deformed. The first part of deformation is called "elastic"
and if you ONLY deform the item in the elastic range it will spring back 100%. A great
example is a - - - - wait for it - - - SPRING. Properly designed springs are always operating
in the elastic range.

When you want to permanently deform something (like size a case smaller) you have to
go through and past the elastic range, into the plastic range. Only the plastic portion of the
deformation is permanent - and when unloaded, the permanent (plastic) part of the deformation
will stay and the elastic part springs back.

ALL metals work this way - although some extremely brittle ones have almost
no plastic range and just snap after a tiny bit of plastic at the end of the elastic part. Some
metals (like lead) have a very small elastic range, and go plastic very early, so the springback
is very small - but it is there.

Bill

You're welcome. One of the reasons I spent 6+ yrs in engineering school is so that
I could understand how things really work. I hope that sometimes I can clearly
pass on some factual info that will help others figure something out.

Bill

This type of deformation is irreversible. However, an object in the plastic deformation range will first have undergone elastic deformation, which is reversible, so the object will return part way to its original shape. Soft thermoplastics have a rather large plastic deformation range as do ductile metals such as copper, silver, and gold. Steel does, too, but not cast iron. Hard thermosetting plastics, rubber, crystals, and ceramics have minimal plastic deformation ranges. One material with a large plastic deformation range is wet chewing gum, which can be stretched dozens of times its original length.

http://en.wikipedia.org/wiki/Deforma...engineering%29

For many ductile metals, tensile loading applied to a sample will cause it to behave in an elastic manner. Each increment of load is accompanied by a proportional increment in extension, and when the load is removed, the piece returns exactly to its original size. However, once the load exceeds some threshold (the yield strength), the extension increases more rapidly than in the elastic region, and when the load is removed, some amount of the extension remains.

http://en.wikipedia.org/wiki/Plasticity_%28physics%29

[Colorado4wheel]

http://s145.photobucket.com/albums/r...7706856914.mp4

Video. It's not friction that is causing the case to not go in. If the case was the same size as the die it would go in with a reasonable amount of force as I applied in the video.

Sorry about the sarcastic tone at the end.

The Links I provided, the statement from a 6 year engineering student and a basic examination of of just sizing and bending metal should lead you to understand that every metal has some spring back after being bent. If you push hard enough (like with a press) you can overcome the spring back in the brass. It's the same when we size our lead bullets. The last bullet is stuck in the sizing die. You push it out and put it right back in you can feel it being squeezed again. Even a soft lead has some spring back (elastic range).

I'm done.

[Char-Gar]

Mr. 4wheel... I really don't have a dog in this fight, but you are whipping a dead horse. Everybody either has their own opinion or just really doesn't care about this issue. From here on out, it just looks like something personal.

Do yourself and everybody else a favor and just let it go. You are not going to convince anybody of anything at this point.

[Colorado4wheel]

I said I would post the video so I did.