Shoulder bumping

[Ronin]

The issue with all this measuring is without an expensive custom made die to address the issues that may or may not be raised from measuring you can’t do much about it anyway other than full length size or neck size your brass 

Cutting .040” or more off the base of a factory die is a well known fix for brass that is awkward to full length size or for a die that just won’t resize enough 

There are also some cartridges with known issues of incompatibility with die and chamber (260 Ackley, 6.5 Skan, 300 NM for example)

Your rifle chamber may have been cut with a quality reamer to perfection but brass won’t re size properly in your factory die 

Difficult fix without recutting the die (almost impossible as they’re hardened)

There is a very well respected rifle smith (Alex Wheeler) in the states who addresses the issue of how to size cases properly in a very simple video made several (4) years ago 

A video that’s seems to have been repeated several times by others

Use this method - it works for all my rifles which invariably shoot

 

[Popsbengo]

Nice and simply explained.  It's pretty much what I did to determine what to bump my .338 to. I use his method finding the lands touch point too.

The gauge is useful to help diagnose where the problem might be even if it's something I can't directly solve.

[Ronin]

The die is simply a cone shape and cylinder shape resizing a cone shape and cylinder shape -  measuring various increments of the cone isn’t going to assist you unless you have a die that EXACTLY replicated the chamber less .003” overall to allow sizing over almost the entire area of the case (from web upwards of a vertical case )

Measuring diameters at various points  just provides you with more perceived problems to answer unnecessarily  

Size the case sufficiently to allow the bolt to close as per Alex Wheelers video 

I don’t follow the “I have the solution, now what was the problem” ethos 

[Popsbengo]

7 minutes ago, Ronin said:

The die is simply a cone shape and cylinder shape resizing a cone shape and cylinder shape -  measuring various increments of the cone isn’t going to assist you unless you have a die that EXACTLY replicated the chamber less .003” overall to allow sizing over almost the entire area of the case (from web upwards of a vertical case )

Measuring diameters at various points  just provides you with more perceived problems to answer unnecessarily  

Size the case sufficiently to allow the bolt to close as per Alex Wheelers video 

I don’t follow the “I have the solution, now what was the problem” ethos 

Fair point - although I think it's interesting to know a bit more about what's happening:  wouldn't buy a gauge but 15 mins with a scrap piece of aluminium in the lathe costs me nowt.

When I had a problem with 'once fired brass' that I purchased, it was not clear to me if it was tight because of length or diameter.  Nice to know what's what.

[Ronin]

Ja 

 

but what doe it tell you in interpretable intel

 

Nothing   

[Popsbengo]

some cases are bigger than others at particular points 😁

It also would allow an understanding of the amount the case 'swells' and is reformed by sizing.  What that means in case life I do not (yet) know..

[KABOOM]

On 2/11/2020 at 6:10 AM, 6.5 shooter said:

Hi all,

up until now I have been solely a neck sizer but I want to bump the shoulders back a little. 
I have all redding type s competition die sets and the only way possible with these die sets to bump the shoulder back is to use the FL sizer die and adjust it accordingly but I dont want to size the body. 
I dont want to have to buy forster shoulder bump dies for all my calibres so im thinking I will have to get a machinist to ream the walls of my FL dies out a little?

unless im missing something does anyone else have a different idea or how does everyone else carryout this task without full length sizing?

thanks

Sinclair International sells shims for use with a full length resize die these go under the die and provide a repeatable means of shoulder bump control. I haven't used them however they make sound mechanical sense. I set my fl dies to not touch the shoulder unless after several loadings its hard to chamber the case then I screw the die farther down experiment and when ease of chambering is achieved I quit. While simplistic it works and I get 10 shots out of my brass.

[Big Al]

On 4/23/2020 at 3:08 PM, Ronin said:

The issue with all this measuring is without an expensive custom made die to address the issues that may or may not be raised from measuring you can’t do much about it anyway other than full length size or neck size your brass .

 

On 4/23/2020 at 5:07 PM, Ronin said:

The die is simply a cone shape and cylinder shape resizing a cone shape and cylinder shape -  measuring various increments of the cone isn’t going to assist you unless you have a die that EXACTLY replicated the chamber less .003” overall to allow sizing over almost the entire area of the case (from web upwards of a vertical case )

Measuring diameters at various points  just provides you with more perceived problems to answer unnecessarily  

Size the case sufficiently to allow the bolt to close as per Alex Wheelers video 

I don’t follow the “I have the solution, now what was the problem” ethos 

Dont you still charge people to build rifles for them?

Is this really the sum of your knowledge or are you just fooling with us?

I cant imagine how life in the dark like this must be.

 

[Ronin]

Life is perfectly enlightened 

Yes I build all manner of custom rifles - as you do know  - you asked a whole heap of questions about doing so (how do I do this, how do I do that etc etc) on here (UKVARMINTING) prior to setting up as a rifle builder yourself 

You speak of measuring cases to judge how much needs to be resized at increments at certain points 

That may well allow you to judge how much that particular point is being resized but unless you have custom made die it’s highly likely you’ll bump the shoulder too much before sizing the brass at x y or z points 

The most effective method to judge how much to resize is by using Alex Wheelers method and touch the shoulder sufficiently to allow the bolt to drop with slight pressure (I think you’ve also created a similar video )

Yes, collet (at the base of the case ) die are effective for re sizing belted magnum cases that grow above the belt - that may be an effective conduit for measuring and small base body dies useful for some rifles with chambers cut oversize or for people who insist on using neck dies only and then find they are unable to close the bolt on fired brass

Unless one takes a chamber cast or one has the reamer that cut the chamber to give an accurate indication of how much one needs to reduce the fired case to be resized - again I refer back to Alex’s video as being the effective method to gauge how much yo bump the shoulder of the case to resize properly 

However I don’t think measuring at increments above the base of the case to be useful other than to create a new problem to “fix”

A bit like cutting threads slightly undersize so a thread can be ceracoated .....’not something I would do

The advice you are giving may cause some to oversize their brass thinking the body of the brass isn’t being touched by the die - size too far / bump the shoulder too much causing excessive headspace in the chamber and a dangerous situation to arise 

Again not the advice I would encourage people to follow 

[Popsbengo]

I note your concern Ronin, however, I think it's perfectly possible some of us can manage to use any additional data without leaping to over bumping and causing headspace issues.  

[Ronin]

1 hour ago, Popsbengo said:

I note your concern Ronin, however, I think it's perfectly possible some of us can manage to use any additional data without leaping to over bumping and causing headspace issues.  

 

Thats a dangerous assumption to follow 

You would be surprised at how poor some reloading practices are after seeing some of the mess ups of people in the trade, it isn’t something I’d bet money.

Some reloaders live on the ragged edge of safety at the best of times 

[Big Al]

1 hour ago, Ronin said:

Life is perfectly enlightened 

Yes I build all manner of custom rifles - as you do know  - you asked a whole heap of questions about doing so (how do I do this, how do I do that etc etc) on here (UKVARMINTING) prior to setting up as a rifle builder yourself 

You speak of measuring cases to judge how much needs to be resized at increments at certain points 

That may well allow you to judge how much that particular point is being resized but unless you have custom made die it’s highly likely you’ll bump the shoulder too much before sizing the brass at x y or z points 

The most effective method to judge how much to resize is by using Alex Wheelers method and touch the shoulder sufficiently to allow the bolt to drop with slight pressure (I think you’ve also created a similar video )

Yes, collet (at the base of the case ) die are effective for re sizing belted magnum cases that grow above the belt - that may be an effective conduit for measuring and small base body dies useful for some rifles with chambers cut oversize or for people who insist on using neck dies only and then find they are unable to close the bolt on fired brass

Unless one takes a chamber cast or one has the reamer that cut the chamber to give an accurate indication of how much one needs to reduce the fired case to be resized - again I refer back to Alex’s video as being the effective method to gauge how much yo bump the shoulder of the case to resize properly 

However I don’t think measuring at increments above the base of the case to be useful other than to create a new problem to “fix”

A bit like cutting threads slightly undersize so a thread can be ceracoated .....’not something I would do

The advice you are giving may cause some to oversize their brass thinking the body of the brass isn’t being touched by the die - size too far / bump the shoulder too much causing excessive headspace in the chamber and a dangerous situation to arise 

Again not the advice I would encourage people to follow 

Earlier in this thread I spoke about people quoting dogmatically or being to lazy or not well researched enough to know the truth. Nothing you are saying here falls outside of this description and to be honest nothing you have said appears in the slightest bit helpful to the original poster or the lads who have engaged in the discussion. To me at least, you come over as  "this is all a waste of time and just do what Alex Wheeler says". Its seemed to me that you had read the thread and decided to put your foot down with authority based on being utterly unhelpful or perhaps because your a moderator, who knows? That said it certainly wouldn't be the first time you have sniped at stuff Ive said before and you do see to have a habit of questioning other peoples ways, I saw it with another rifle builder only recently and again you were put in your place.

When I joined this forum 6yrs ago I asked lots of questions here and in lots of other places as well. I became interested in long range shooting 6yrs ago and the only way to learn is to ask, something Im not afraid to do.  Something significant I did learn though from all the questions was just how many people didnt really now the answers and so out came the same old dogma, stuff that I have since proven to myself to be inaccurate through my own thorough testing and competition successes. I have never claimed to know secrets other rifle builders dont but then from time to time one or two surprise me by revealing just how little they really do know.

As for building the rifles and then things like custom dies. I use basic good engineering practice, stuff I learned years ago as an apprentice and and developed as my trade and measuring is key to everything. Precision engineering is not something new to me, not something Ive dabbled with out of the shed for a while as a sideline. My background is toolmaking, look it up. Reloading dies are just simple things that dont take much understanding, thats why I was surprised at your comments as you dont seem to get it. 

The method you champion in the video from Alex is fine, its good advice to cover the basic aspect of head spacing . Alex is a lad a bit like myself in that he is relatively new to rifle building and it wasnt that long ago he asked lots of questions as well. I have corresponded with him at length and interestingly he shares a similar outlook to myself in that he doesnt buy into the dogma either, preferring to test extensively and draw his own conclusions from that, I like his attitude and he has made a good name for himself.

In relation to the video, if the sizing die thats being used is a decent match for the rifle chamber then that method works well and Im fairly sure that was all Alex was trying to show. He was showing what the 'touch' or 'zero' point of headspace felt like then bumping the shoulder back from there his desired amount. The point he was making was that to just dogmatically (theres that word again!) bump the shoulder of a fired case by 0.002" as Ive read here and on so many other places online just wasnt an accurate way to do it, in that I agree entirely.

However, that method alone isn't foolproof if your resizing die is sloppy and not resizing sufficiently at the .200" mark.

If a case has swollen, particularly with a high pressure charge it can quite easily give a false impression that the drag on the bolt handle is the headspace when in fact its the .200" area of the case body that is still tight in the chamber. So what does the inexperienced guy do then? He bumps the shoulder a little more thinking that this is his problem area only to find the bolt still drags, so a little more and a little more until eventually he has bumped the shoulder heaven knows how much before the bolt finally slips down of its own accord. Unbeknown to the chap it was always the .200" mark that was too big and by the time he has sized that part of the case he has actually pushed the shoulder so far back he is at risk of getting case head separation. All this because he didnt take some basic measurements with a simple tool easily made!

What I have said is that to measure gives the reloader knowledge, with knowledge comes options. If the sizing die isn't working properly then measurements will tell you that, you dont need a cast of the chamber to know the chamber shape and dimensions, your fired brass will tell you all you need if you know what your looking for. Im amazed you think you need the chamber reamer or a chamber cast to know this? how dark is it over there?

Popsbengo gives a good example earlier in this thread about how measuring like I suggest has confirmed something that happened to him recently yet he wasnt sure how, know he knows how.

Ive highlighted your suggestion of my advice leading to a dangerous situation with headspace, again Im struggling how you come to this conclusion? Ive explained what a clicker feels like and if your not getting them then you dont need to be worrying about sizing at the .200" as much as at the shoulder, if you are then you do if you want a bolt that cycles smoothly. To think you should only look at one measurement at the shoulder and ignore the case body is just daft and stinks of the old dogma Im so tired of reading.

 

 

 

[Big Al]

30 minutes ago, Ronin said:

 

Thats a dangerous assumption to follow 

You would be surprised at how poor some reloading practices are after seeing some of the mess ups of people in the trade, it isn’t something I’d bet money.

Some reloaders live on the ragged edge of safety at the best of times 

You really are up yourself lad.

Give people information and let them decide if they are capable, are you the reloading police now as well?

I will leave you to have the last word here as I really dont have the time to go back and forth with you. The good thing about forums is that the people will read and make their own minds up and they will take from it what they will.

[One on top of two]

Big al 

you sir are a f3cKING  legend . Theres not one of your posts I Have ever disagreed with ! Don’t you dare go anywhere.

 
 

regards a grumpy old keeper 

[Popsbengo]

11 minutes ago, One on top of two said:

Big al 

you sir are a f3cKING  legend . Theres not one of your posts I Have ever disagreed with ! Don’t you dare go anywhere.

 
 

regards a grumpy old keeper 

+1

[Ronin]

Ok

 

cheers for the diatribe- didnt really need a sleep aid after that resume’

 

Question - 

a reloader wants to reduce their case body diameter by .001”  as their chamber is tight or they’ve used a slightly higher charge and the body has swelled a bit

The case is 6.5/47 Lapua

They full length size the brass down so the body of the die is in contact with the case shoulder (full length re sizing) 

 

But they find the case slightly tight still and decide to reduce the diameter by .001” 

 

Using the F L sizing die - how far will the shoulder be “bumped” by resizing / reducing  the diameter of the case body by .001” 

 

 

[Popsbengo]

13 minutes ago, Ronin said:

Ok

cheers for the diatribe- didnt really need a sleep aid after that resume’

Question - 

a reloader wants to reduce their case body diameter by .001”  as their chamber is tight or they’ve used a slightly higher charge and the body has swelled a bit

The case is 6.5/47 Lapua

They full length size the brass down so the body of the die is in contact with the case shoulder (full length re sizing) 

But they find the case slightly tight still and decide to reduce the diameter by .001” 

Using the F L sizing die - how far will the shoulder be “bumped” by resizing / reducing  the diameter of the case body by .001” 

Ronin, I think you're missing the point.  It's a diagnostic aid not a guide to sizing (at least that's how I use it). It does not follow that someone will automatically over bump the case in pursuit of reducing the body - I'd hope any reloader would have some gumption there and if they don't, well, it's free world !

I discovered today that my fire formed .308 cases are + 0.001 at .200 and +0.001 at .500 when compared to brand new Lapua (sample of 10 cases).  That's nice to know for me, it may be irrelevant in the big scheme but so what ??

[Popsbengo]

Additional to the above.

I've just finished measuring the troublesome .338 "once fired" brass against new and fire formed in my chamber.

The second hand stuff is 0.003" over new at the 0.500 position ! It's no wonder it was as tight as buggery in the F/L die.  It must have been fired out of a very sloppy chamber.  makes me wonder just how much I want that brass (watch out for me selling  😂)

Again, interesting but not a mad pursuit to reduce it back to standard at all costs...

[Big Al]

4 hours ago, Ronin said:

Ok

 

cheers for the diatribe- didnt really need a sleep aid after that resume’

 

Question - 

a reloader wants to reduce their case body diameter by .001”  as their chamber is tight or they’ve used a slightly higher charge and the body has swelled a bit

The case is 6.5/47 Lapua

They full length size the brass down so the body of the die is in contact with the case shoulder (full length re sizing) 

 

But they find the case slightly tight still and decide to reduce the diameter by .001” 

 

Using the F L sizing die - how far will the shoulder be “bumped” by resizing / reducing  the diameter of the case body by .001” 

 

 

 Did you read everything that was written thoroughly enough and understand it before you entered this discussion? 

With respect it doesn't seem so to to me, it seems like you booled in to slap me down for suggesting measuring cases at .200" was either a bad idea or at best pointless because we couldn't do anything about it, now your struggling to dig yourself out of the hole you have made for yourself.

I said earlier I was done but to be honest your making it so easy for me to look good that I might as well continue since its lockdown and it will most likely bring me some extra work.

You seem fixated on a particular scenario and its stopping you seeing the bigger picture. Nobody in this discussion said anything to suggest resizing at .200" was more important than headspace and that it should be pursued above all other things, especially safety. 

Dies are often sloppy mass produced things, other times they can be very tight, especially if the rifle has a sloppy chamber. Even a custom barrel is no guarantee of avoiding a sloppy chamber either through some builders being ignorant to what reamers should be doing or by polishing marked chambers to clean them up instead of re-cutting them. Rifle chambers are probably as bad in terms of size relative to spec as dies so getting good brass fit isn't always easy and many people are just in the dark as to know where the problems lie.

The scenario you are hanging on to above is only one scenario and in that case maybe the reloader might not get his body resized safely by 0.001" if his shoulder is already heavily touching the bottom of the die and the fit is good with both shoulder angles at exactly the same angle. As you suggest he might end up pushing his shoulder way back and risk case head separation due to excessive headspace. But that is only one of many scenarios so should we avoid doing anything for fear of one such scenario?

In one of many other different scenarios Ive also seen what can happen when you reach the point where effective sizing happens at the .200" mark and shoulder bump length actually grows!

Think of the brass like a balloon, you squeeze the bottom, what happens to the top? it grows! So how can that be if it was already touching at the shoulder you might ask? The answer is tolerances in reamer making for both dies and chambers. Let me explain even though it pisses me off to teach you stuff you should really know since you come across as all knowing.

Take a typical chamber reamer and measure the shoulder angle using some proper measuring gear like I have access to and you will see its rarely 30 degrees if that is the spec, or 23 or 40 or whatever its meant to be. Ive seen reamer shoulder angles out by one degree quite often and 30 minutes is nothing. I even had a UK reamer maker supply me with a 22/250 reamer where the shoulder was ground wrong by 2 degrees and I sent it back. He initially denied there could be anything wrong with his first class product but once enlightened he acknowledged the mistake and gave me a refund, I would never buy from him again as the man is a fool. The more you look at reamers the more you realise many of them are shite, thankfully my current supplier makes them bang on the money every time, he has the measuring capabilities to check and the machinery to hold the right tolerances.

OK, back to the case that grew in shoulder bump length when it was squeezed at the bottom, this was clearly as a result of the chamber shoulder angle and the die shoulder angle being quite different. Take a scenario where there is a discrepancy on tolerance of 30 minutes in opposing directions between the reamer that cut the chamber and the different reamer that cut the die. Overall you have an angle discrepancy of 1 degree, thats plenty of room for additional brass movement in an upward direction when pushed hard enough. It would happen with even less never mind 1 degree as many should bump gauges only pick up on a sharp single datum surface that can easily be moved in this example. It doesnt go downwards because the web is too thick and strong to accept whats being forced around, instead it goes upwards as the route of least resistance and Ive seen shoulder bump length grow by as much as 0.003" before when the .200" mark is resized a couple of thou. All this by simple observation and measurement and no daft forces applied with the press.

So where does all this bring us?

Well, it shows some people just how closely I look at the work I do and it shows that you dont look at things with the same level of detail or distrust in the tooling you are given as I do. To be fair though I doubt you would ever question that your reamers weren't what they should be because your experience in engineering is tinkering in your shed in the garden shed, mine was once at the sharp end where we checked everything as mistakes could be extremely costly.

Checking our fired brass and taking measurements (which was what this discussion was about) does no harm, I just tried to offer an insight into it from my perspective and people seem grateful for that. The more someone knows by measuring the more they can improve their reloading, the more chance they can see if the sizing die they have is actually a good match for the chamber they have and in many cases then can them improve the die themselves or give it to someone who can improve it for them or buy another in the hope its a better fit.

Whats the problem with all that I wonder?

[terryh]

FFS 🙄

Back to the OP

Just adjust your FL until shoulder’s pushed back a few thou on a fired case and go and shoot.

If you want to play a bit get a set of die shims, you need nothing more to control things nicely.

T

 

[Big Al]

8 minutes ago, terryh said:

FFS 🙄

Back to the OP

Just adjust your FL until shoulder’s pushed back a few thou on a fired case and go and shoot.

If you want to play a bit get a set of die shims, you need nothing more to control things nicely.

T

 

This is just the dogmatic reply I have been talking about, clear as mud and utterly useless in many situations while teaching people nothing.

In light of the discussion why waste your time with such a feeble contribution Terry?

 

[terryh]

Al,

Please refrain from casting aspersions on people who you do not know, not polite and comes over as a bit rude IMHO

It appears that if anyone says anything you do not agree or understand you go off on one - it becomes a bit boring after a while.(ref. AMP annealed/‘free’ downloads/how business works)

Not dogma - just works.

I was not disagreeing with anything you’ve been saying, it might be correct, who knows?

But does the OP need to go into all that to get his rifle to function safely - no.

So just accept, for once,  that your opinion /method might not be the only one in the universe - possibly, yes??

T

[Big Al]

13 hours ago, terryh said:

Al,

Please refrain from casting aspersions on people who you do not know, not polite and comes over as a bit rude IMHO

It appears that if anyone says anything you do not agree or understand you go off on one - it becomes a bit boring after a while.(ref. AMP annealed/‘free’ downloads/how business works)

Not dogma - just works.

I was not disagreeing with anything you’ve been saying, it might be correct, who knows?

But does the OP need to go into all that to get his rifle to function safely - no.

So just accept, for once,  that your opinion /method might not be the only one in the universe - possibly, yes??

T

Terry, with respect its clear by what Ive written that at no time have I suggested my method is the only one in the universe. Its not even my method, its basic measuring that far more reloaders than myself take notice of.

As for aspersions, none of those here, I have simply pointed out facts.

I have replied in detail because my opinions were challenged, how else does someone reply unless you want five word grunts that help nobody?

You know fine well threads develop from an original post often to many pages and for as long as there is a point to discuss or debate I will do that, its my right as much as anyones on any forum unless of course I end up banned for it.

There is a pattern here which is talked about widely outside of this forum and that is one of moderators ganging up on people if things aren't going their way, it becomes tiresome and is one of the main reasons I dont post here much.

I will leave it at that.

[MJR]

On 2/11/2020 at 1:10 PM, 6.5 shooter said:

Hi all,

up until now I have been solely a neck sizer but I want to bump the shoulders back a little. 
I have all redding type s competition die sets and the only way possible with these die sets to bump the shoulder back is to use the FL sizer die and adjust it accordingly but I dont want to size the body. 
I dont want to have to buy forster shoulder bump dies for all my calibres so im thinking I will have to get a machinist to ream the walls of my FL dies out a little?

unless im missing something does anyone else have a different idea or how does everyone else carryout this task without full length sizing?

thanks

You should be able to bump the shoulders back a few thousandths with the FL dies without drastically resizing the body although if you do I doubt it would be sufficient as to cause a detriment to accuracy. You do not say if you anneal or not or how many times the brass has been fired and if your chamber is standard or not? If you don't anneal, from my experience the shoulder bumping can be less consistent than that of annealed brass but you'll have to try it. 

Try not to get side tracked by the other information offered by some other posts. A lot of information offered is not really relevant to simply bumping shoulders back a few thou. Once you have bumped the shoulders try a case in your chamber and see how it feels. Prior good advise is this is best done with any spring ejector or fire mechanism removed from the bolt as it provides better feel to the bolt. If you are sure your shoulders have been bumped and the case still gives resistance to closing the bolt easily then its time to investigate possible other causes. I would suggest looking at the overall case length and checking that it is within spec for your calibre/chamber and trimming if necessary. If the case still doesn't chamber nicely then start looking at diameter changes on the case body. To resize the body only use a body die and forget any notion of trying to reduce the diameter of the case drastically with a FL die as doing so will bump the shoulder still further. That may result in poor ignition as the firing pin pushes the case forward or if resized excessively a dangerous over pressure situation if your reloads are already in the upper part of powder charge. 

[Ronin]

Al you still haven’t answered the question 

How much will the shoulder be moved if you use a FL size die to reduce the case body diameter by .001” if the die is touching the shoulder (standard CIP 6.5x47 lapua case ) 

I’m not referring to using a small base body die where the shoulder is not interfered with.

 

Simple question - what’s the answer ?