6ppc neck clearance ??

I like to have a case that has been fired neck sized only with warm loads, about 3 times as a bump back reference. Some load do not cause a case to get tight, shoulder to head, in one firing, so you really don't need to bump back shoulders from there. If you have a tight case for reference, you can set your die to produce cases that are .001 shorter (shoulder to head) than it is, otherwise your brass is working too much during the firing cycle. Your sized case look about right compared to your sized one.
 
Tsingleton said:
I apologize if I have miss stated something or phrased it wrong.
If this is so, and the brass does not grow when fired. Why do people say That a round with a 40 degree shoulder doesn't grow as much as a 30 degree thus requiring less trimming?

I have just began to loose some ppc brass, it is separating at the head. Probably 25x loaded. I bump the shoulder back .001 with my Harrel die. I don't think I am running it up into it to much or using it improperly. But I do have to trim regularly maybe not every firing but probably every other to keep it the same.

help me understand this
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Tsingleton, good questions.


Why do people say That a round with a 40 degree shoulder doesn't grow as much as a 30 degree thus requiring less trimming?
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2 reasons come to mind.... #1, generally wildcat cartridges or non-standard cartridges like a 40 degree-shouldered cases dictate that one buy a custom sizing die which increases the chances of achieving better fit and #2, 40 degree cases better resist "sliding thru the die"..... it's simply harder to get the brass to slip around those two sharp corners so the cases are more resistant to improper die setup.

The WHY is what's critical here :)

I've got this sign on my wall....

The Man Who Learns How To Do A Job Will Always Have Work
The Man Who Learns Why Will Always Be His Boss

Which brings us to the second part of your post.

I have just began to loose some ppc brass, it is separating at the head. Probably 25x loaded. I bump the shoulder back .001 with my Harrel die. I don't think I am running it up into it to much or using it improperly. But I do have to trim regularly maybe not every firing but probably every other to keep it the same.
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I'm glad that you've actually reloaded enough to validate my initial assertion, most people out there are just guessing! Really.... very few keyboard shootists have actually reloaded the same case 25 times, VERY few.

Your die IS set too deep. Sounds like you've got the required scrupulous die fit, but you are over-sizing.

Here are some items to chew on, maybe also some things to try.

-All guns are different. Different brands/makes/styles of rifles have different flex characteristics and require different sizing methods/settings
-Brass changes as it ages, sometimes necessitating different die settings. Some periodically anneal to combat this. I choose not to, barrel life is too short for me to be wasting shots! Others anneal every firing, again, doesn't work for me. I adjust my dies/lube/etc. Skip's Die Shims are wonderful things, I keep about 6 sets of them floating around my gear. Die shims and lube, real ways to change sizing effect quickly.
-Which brings us to lube. Different lubes will produce different results. I've sized t'ousands of cases with BBS :) Not a lube A'tall.... but proper setup requires very little sizing effect.
-re Die settings... If my die EVER touches my shellholder I walk over to the beltsander or benchgrinder and POSTHASTE I do grind the bottom off most abruptly....
-Harrell's dies, one characteristic of these and all bushing-style dies is that they leave an area of the N/S junction un-sized. Sometimes this can enter into the melange.
-Measurements/methods/results vary..... You feel that you're setting your shoulders back a thou and maybe you are, but a thou PLUS a fuzz, or a thou MINUS a fuzz can make for a difference of almost a thou WITHIN a thou.... To state my position succinctly I don't ever presume to know a measurement.

"Measurements" suck, I don't trust 'em.

I just DON'T.

I measure a lot but I GAUGE everything by results. Your RESULTS are casehead separation..... and to quote my buddy Jesse, "Ya' cain't argue wit' da' facts!"

Try backing the die off a little :)

The Skipper's Die Shims

Rock On

al
 
al

Thanks for taking the time to explain. Not just correct and go on. I am just trying to figure this thing out. What you are talking about makes sense and is what I am seeing.
I will back my die up a little hopefully this will help my trimming and neck thickness problems

Thanks

Tim
 
The easiest tool for measuring how much you've pushed your case's shoulder back [headspaced your brass]: http://www.larrywillis.com/

"Our patented Digital Headspace Gauge shows the exact clearance (at the shoulder) that YOUR handloads will have in YOUR particular chamber. Remember, a fired case is like a perfect casting of your chamber. Simply calibrate this gauge to your rifle by inserting one of your fired cases, and press the "zero" button. Then insert one of your handloads, and the gauge will display your chamber clearance. This is the most accurate way to adjust your die height - without guessing." :)
 
I guess that I will have to disagree on that one. The little brass piece that Lynwood Harrell gives you does just fine. I have all sorts of tools, the Hornady one, and a piece of barrel that has the front of the chamber in it. I can even take the barrel off and use a depth mike and sleeve to measure down to the case head before and after sizing, if I should be so foolish, Lynwood's little gauge works very well for setting your PPC FL die. For that particular application, you don't need anything else.
 
abintx said:
The easiest tool for measuring how much you've pushed your case's shoulder back [headspaced your brass]: http://www.larrywillis.com/
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Maybe. But the cheapest in the one Harrell sends with his die, or one the 'smith makes with the chambering reamer & a piece of barrel scrap. Of course, you do need a set of calipers...

I see a lot of branding talk in this thread. They're all tools, guys, and you need to learn how to use what you got. If you keep spending on the latest fashion, it's only the illusion of progress.

Carbide mandrel, sure (not carbide cutter). What, about $35 each? I've got a couple. But Boyd's trick on not having such a tight fit works with steel. Or keeping the tool cold as well as clean, but "cold" is a lot of work. "Clean" is the key.

BTW, I get about .0002 difference between using an electric drill versus turning by hand. That's just me I suppose, with my weak hands and the heavy drill. I'll use either method, but not both on the same set of cases. Not that I have proof that .0002 matters.

Remember the long acrimonious thread on annealing? Well, Phil Bower set an IBS 10-shot 1K record a while back.

http://bulletin.accurateshooter.com...00-yd-nationals-bower-breaks-hg-group-record/

Good shooting Phil. Less well known is that about half his cases had split necks. Before firing. Anyone who thinks Phil's record was a flash-in-the-pan just never shot against Phil at the Original Pennsylvania 1000 Yard Benchrest Club.

http://www.pa1000yard.com/

And Phil made (occasionally) one of the best annealers around. Wonder if he annealed those split necks?

Then there is all this talk about even bullet release. Now if you talk to Bob Hart (the younger), he'll tell you the best way to get even bullet release is to use a short neck. Like the .30 Hart. Or, I suppose, the Wolf Pup. But then half the brethr'n think a long neck is beneficial, for "bullet alignment," or sometimes for "neck tension." Which is it going to be, guys, what's "best"?

Take a look at that Wolf Pup

https://www.google.com/search?q=.30...CkD4LC9QTlsYGADw&ved=0CDYQsAQ&biw=755&bih=485

Don't think anyone will argue about it's performance...

Proof comes from the target, and tools are just that. They don't use themselves.

Etc.

Edit:

Apparently written while Boyd was writing. I'm just slower.
 
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Boyd Allen said:
I guess that I will have to disagree on that one. The little brass piece that Lynwood Harrell gives you does just fine. I have all sorts of tools, the Hornady one, and a piece of barrel that has the front of the chamber in it. I can even take the barrel off and use a depth mike and sleeve to measure down to the case head before and after sizing, if I should be so foolish, Lynwood's little gauge works very well for setting your PPC FL die. For that particular application, you don't need anything else.
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I too have all sorts of tools, including Harrell's and Hornady's. With both of them I'm applying the pressure to extract a reading, which my be slightly different, each time I use it.

With Larry's gauge, the gauge itself, provides a uniform downward pressure, using a spring and gravity, to provide the most consistent readings. I prefer the mechanical vice the human element.

Kind of like turning brass with a lathe versus a handheld turner. Just personal preference. :)
 
I think that having well made tools that work well is one of the pleasures of our hobby. I just wanted to make it perfectly clear that changing to the tool that you prefer, will not improve his situation as far as gauging his shoulder bump. If the wrench fits the bolt and allows room for it to be turned, it is not the problem.
 
mturner said:
If you have a true .003" over the pressure ring, you have more than enough clearance. I would recommend a minimum of .002" measuring a seated bullet over the pressure ring. You could have as much as .0035" to .004" clearance with your current setup. I consider this too much clearance because you are working your brass more than you need to. Just because the reamer has a .262" neck, the reamers often cut .0005" over their actual diameter. The reamers also measure closer to .2625" in many cases. The reamer tolerance is usually -.0000" and +.0004". I recommend getting an accurate measurement on the neck diameter of your chamber.

Michael
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This time, I happened to have to prepare a set of .220 Lapua cases for a newly installed 6PPC HV Krieger barrel on my Teddy.
As usual, before starting anything connected with cases, I like to make sure I know what I’ll be doing, and the first step is to measure the neck of the chamber and not trust the figure engraved on the reamer.
The neck measured .2623.
After reading the article, by J. Mock, about Jack Neary summarizing his views on case preparation I was willing to give it a try. He quotes B. Forrester that, as far as neck tension is concerned, ‘thinner is better’ and for a .263 chambering he advises to turn the necks at .0081/.0082 max. My problem was: what dimension should I turn for my slightly smaller chamber to keep the same proportion as advocated by Mr Neary? I endeavoured to make some calculations, didn’t like the result and chose, wisely as it happened, to check with my wife who had had the benefit of a more scientific and mathematical education than I.
She soon put me right and it may help some other poor soul obsessed with the vanity of doing things just so. I won’t bore you with abstruse theories but just set the example taking as a base Mr Neary’s postulate:
.263 -> .0082
.2623 ->?
Just do: .0082 x .2623 /.263 = .008178
Doesn’t change much for all practical purposes but this becomes very obvious if you have a .268 chamber…

Please, feel free to check the validity of the calculation and its relevance with Jack Neary's position. I wrote the above December 2010.
 
To keep the same clearance with a larger neck diameter that Neary recommends for a .262, subtract .262 from the larger neck diameter, divide the answer by two, and add that to the neck thickness that he recommended for a .262 neck. For example, if you have a .268 neck, subtracting .262 would give .006, half of that is .003, so the correct thickness would be .0111 or .0112, giving the same clearance as Neary's recommended .0081 to .0082 does for a .262 neck. Of course the point about the actual neck diameter being slightly different than the specified size is a good one.

I have shoot good groups at 100 using everything from under .001 total clearance, to .003. The reason that I am currently working in the .0025 to .003 range (depending on the diameter of the bullet) is that I believe that I may have been blind to a potential difference at 200 because I do most of my shooting at 100, and I think that Jack has a good enough record to be worth listening to.
 
Boyd Allen said:
To keep the same clearance with a larger neck diameter that Neary recommends for a .262, subtract .262 from the larger neck diameter, divide the answer by two, and add that to the neck thickness that he recommended for a .262 neck. For example, if you have a .268 neck, subtracting .262 would give .006, half of that is .003, so the correct thickness would be .0111 or .0112, giving the same clearance as Neary's recommended .0081 to .0082 does for a .262 neck. (...).
Click to expand...
Thanks for your comment: I stand corrected. Your method is so simply evident!
 
I am going to throw a wrench into some established thought processess as it pertains to FL sizing. The "Thingy you get from Harrell's can be ok and it can also give wrong measurements. The reason being is the tolarance of the shoulder angle on the reamer. If it does not contact the shoulder completely or at least in the middle, the measurement you get may be far off. Thus, this is why bumping .001 is causing case seperatation after 25 firings. This is the most likely possibility. The other is the cases...are you using lapua or something else? It is best to have your own reamer and your shoulder bump gage made from it. There is also a nice gage made by a guy in Michigan, I've seen Dwight and many other top shooter use it. But still I'll argue with anyone when it comes to standard PPC BR chamberings...check your die setting by feel, your bolt handle should drop to 90 degrees and then be easily pushed down with one finger. I bet if you check your brass by removing your firing pin, you handle drops all the way down easily.

Also, all dies (even custom FL dies) are not the same. Again, if the shoulder/body angle is off enough, problems with headspacing and overworking brass occur. I highly recommend that you find a die that will size your brass no more than .0005 and it easily chambers. You should be able to fire your brass many times without ever having to reset your die. Why...because you are not overworking the brass.

This all pertains to the PPC. If you can not set your brass by feel in a custom PPC, you had better find another gunsmith because something is seriously wrong (especially if he did your chamber and made your die). What gets most people in trouble is playing with the ppc deminsions on thier chambers, nothing has ever proven better than the standard JGS1045 reamer spec, change the neck diameter if you wish but leave everything else alone. One last parting comment....don't ever...ever...bump ppc shoulders back .002 ... That's to Damn far.

Hovis
 
Hovis,
It seems that you are in the "and" category, rather than the "instead of". That is, you measure and use feel, and I assume that if the bump is at a maximum, and the feel is too tight, that you conclude that you need another die. I do the same thing, but instead of getting a different die, I change the insert in my Vari-Base die to the next smaller size and try again. While I am sure that it is a fine thing to have FL die that was cut by the smith that chambered your barrel, wouldn't you agree that lots of shooters are able to get satisfactory service from dies that were matched to their fired brass, such as Harrell Precision provides? Also, have you seen a lot of out of spec. chamber shoulder angles? How do you check for that ?
Boyd
 
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For the new folks, just wanted to add that the " have FL die that was cut by the smith that chambered your barrel" doesn't mean the FL die is made with the chamber reamer. Doesn't work.

To resize, the resize die has to be smaller than the chamber. Not by much, but it must be smaller.
 
Boyd,

I check every barrel on a used gun I buy by both methods, once I deem the chamber/die fit is ok, I never measure it again. Chambers done by my gunsmith with my reamer is set by feel only. When I had my first BR rifle built, Ed Watson sat down and showed me how to set everything up. No "thingy" ever made an appearance. The only question he asked was...who chambered the barrel. I had a FL die that was not made by my gunsmith and he checked it and the brass and said that it just wouldn't work the way it should. It was to rounded at the neck/shoulder and Shoulder/body junctions and said it would never headspace right. He pulled out a FL die made by Hammond (I think it was the same year Hammond won the supershoot) and sized a piece of brass to fit my rifle and showed me the difference. I still have that die and another made to the same spec by my gunsmith. The newest die is 13 yrs old. I have never ran into a sizing issue but I also don't screw around with chamber deminsions either. It's hard enough to keep track of all the variables that can casue a gun not to shoot so I don't think adding another variable to keep track of is a good idea.

Hovis
 
Thanks for the info. I also keep my reamer at my gunsmith's, and except for testing for an article, have used the same die for years. Changing things that work is not my practice. I guess that the reason that I use the little brass thingy is that for my chambers and dies, when I set the bump with it, I get a good feel, and excellent brass life....and it is fast to do. After screwing up a couple of times starting to size with the die set for old hard brass, with new brass, I have made a practice of taking the die out of the press, and setting it for what ever brass that I am working with, at the start of a session. I use a Lee lock ring, below a Hornady lock ring above it, that locks it to the die. I know about where to start my adjustments, and with the O ring on the Lee ring, I can just turn the die and check the bump, until I get what I am looking for. I also noticed that the slight float that it allows seemed to give me slightly straighter brass.
 
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Hovis
I use Lapua brass. I will check a sized piece in my chamber to see how the bolt closes. My rifle is an older gun smithed by Sealy Masker. Remington action trued and pressed in an aluminum sleeve. I had a new Krieger barrel fitted to it after I bought it.
 
If you already have .003 clearance the only thing increasing will do is shorten your brass life. Most people would say you are already overworking your brass from excess clearance.
 
I did some more checking today. I'm not sure what this means. Possibly my Harrel die is not a good fit.
I backed my die out so when I measure with my brass piece there is no shoulder set back at all.
But the diameter of an un sized case at the shoulder is .003 larger than a sized case. When I lock my micrometer down on an un sized case it slides down 1/4" or so on the sized case. The shoulder measurement with the brass comparator is the same.

Boyd asked me to check this the other day I guess I screwed up some how taking all the measurements.

Is my Harrel die the wrong size?
 
At this point, I wouldn't worry about it. Have you taken a look at the six segments of Jack Neary's workshop on Youtube? I believe that in one of them he speaks to this very issue. How much smaller is sizing making a tight case a little above the extractor groove, and how does your zero bump case feel when you chamber it?
 
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