Modified LEE FL die

U

UlicniTrkac

New member
Hi,
maybe I rushed a little, but its nothing that cant be fixed.

I have a standard Lee 8x57 die set, and I have a CH4D neck sizing bushing die.
My fired brass has a 0.359 OD on the neck. I have made a 0.352 and 0.347 and I have a 0.344 CH4D bushing. I shave the necks of my brass to 0.012.

Today, I took a FL Lee die, and bored out the neck sizing part of it to 0.362, and polished it - it was done on precise equipment, so its concentric - I wanted to make a die that will be able to bump the shoulder, and leave the neck intact, so I can neck size in separate operation.
Maybe this was a dumb move?
After that, I did some sizing, and I found the following - which is odd (I havent tried to chamber the round yet, my rifle is at a gunsmith, having a new stock done) - neck moved forward for 0.003. I am afraid I wont be able to chamber it at all? Or is this normal (since there is no neck for added pressure)?
Thanks
 
I thought the neck usually becomes longer on rifle brass when sizing. When sizing the brass has to go some where. The only place it can go is to be pushed into the neck area.
 
I thought the neck usually becomes longer on rifle brass when sizing. When sizing the brass has to go some where. The only place it can go is to be pushed into the neck area.
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reddog81, that is some good thinking, all the rest of the reloaders think/believe they moved the shoulder back because the distance from the shoulder to the case head gets shorten when sizing. I have said over and over and over etc. I find it impossible to move the shoulder back with a die that has case body support and with that I have never managed to provoke a reloaer to think; all I have managed to do is make them angry.

And then there is brass flow as in 'it has to go somewhere', I chambered a round with .127" clearance between the shoulder of the case and shoulder of the chamber; I pulled the trigger, it was like some kind of a miracle, the shoulder of the case did not move and the case head did not separate. And then I thought about it, and then it became one of those 'and then moments', I marked the shoulder location on the next round and then pulled the trigger. Sure enough, the shoulder did not move.

F. Guffey
 
I know, it is like moving your lawn; mowing your lawn is like immediate neighborhood acceptance' bump is the same thing, if a reloaders desires neighbor hood acceptance on a reloading forum he uses the 'bump' word to describe sizing. There is a remote chance there are only two members of this forum that has instructions that cover press operations for the old days. In the old days bump applied to cam over presses, if the press was not a cam over press, it was not a bump press.

I can not deny it sounds cool to say 'bump the shoulder back', again, I find it impossible to bump a shoulder back. And then there is stretch and flow, or is it both or one or the other.

F. Guffey
 
If a round is fired in a fatter chamber the case expands outward which decreases its length because the brass has to go somewhere. (just like a 9mm) When you size just the body as UlicniTrkac did, without sizing the neck, the brass is squeezed in and up. this pushes the the top portion of the brass toward the mouth. In this case the neck wasn't constrained so it was just pushed up with the rest of the body.
 
If a round is fired in a fatter chamber the case expands outward which decreases its length because the brass has to go somewhere.
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I could say; "think about it" but most responses come from members that are going to respond. If the case head expanded because of pressure there is no need to worry about where the brass went as in "brass has top go somewhere".

When the case head expanded the case head got shorter from the cup above the web to the case head. And then? We apply the "brass has to go somewhere" and I ask: Where did the brass go?

F. Guffey
 
Whether or not 0.003" will matter depends upon your chamber. There is not simple answer that doesn't include more information - most of which is chamber-dependent.


My question, though, is:
Why are you turning/reaming your case necks to 0.012"?



reddog81, that is some good thinking, all the rest of the reloaders think/believe they moved the shoulder back because the distance from the shoulder to the case head gets shorten when sizing. I have said over and over and over etc. I find it impossible to move the shoulder back with a die that has case body support and with that I have never managed to provoke a reloaer to think; all I have managed to do is make them angry.
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Try harder.


When you bump the shoulder, the neck 'gets longer'.
When you size neck diameter down, the neck gets longer (and thicker).
When you size neck diameter up, the neck gets shorter (and thinner).

A cylinder is a very strong structure. Just because it has no internal support, does not mean that it wants to collapse upon itself when pressure is applied.
When pressure is applied to the shoulder of a bottle-neck cartridge, the cylinder and 'conical' shoulder are self-supporting and redirect the pressure to 'extrude' the case into an area with lower resistance: the neck.
 
Today, I took a FL Lee die, and bored out the neck sizing part of it to 0.362, and polished it - it was done on precise equipment, so its concentric - I wanted to make a die that will be able to bump the shoulder, and leave the neck intact, so I can neck size in separate operation.
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lol now you got me confused
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I have been accused of worst; but, I would think a reloader would understand when modifying dies the neck diameter of the full length sizing die is as small as it is going to get. In the big inning of the Internet it was fashionable for reloaders to claim the first thing they get rid of is the sizing ball/neck sizer or they order sizing plugs to fit their needs. With the 8mm57 case I have suggested they form cases from 30/06 cases, when 8mm57 cases are formed from 30/06 cases the necks get thicker because (again) the shoulder does not move but the new neck is formed from part of the shoulder and case body of the 30/06. And then: There has to be a reason, the 8mm57 military chamber is a generous chamber. When tightening the neck is it possible to accomplish that with a thicker neck.

And then it does not surprise me it is confusing when bumping a shoulder; I have made it very clear, I find it is impossible to move the shoulder of a case with a die that has case body support. If I had smart pills I would start selling them, there is no way I can get a reloaders hands off of the key board, if a reloader scribed a case at the shoulder case body juncture before sizing and after sizing there is a remote chance they could figure it out. And then there is the other shoulder movement? AGAIN; I fired a case in a chamber with .127" clearance between the shoulder of the case and shoulder of the chamber, I know, most believe that is too much head space but I pulled the trigger anyhow and the shoulder did not move. SO; I chambered another one of those short cases in my long chamber and pulled the trigger, again, the shoulder did not move, the case did not stretch between the case body and case head.

F. Guffey

And then there was Hatcher;

F. Guffey
 
Lol, excuse me for reading too much online :) during all that reading, I got convinced (somehow) that I will have trouble chambering the round in my rifle if I only neck size my brass.
I use only one rifle with this caliber, and I am the only one that is going to use it again and again. I ve read and heard horror stories about people not being able to close the bolt after just doing the neck sizing - and I still didnt experience that (I m using mine third and fourth time at the moment) with just neck sizing it. Even without any work on my cases, I can close my bolt without any pressure to it, it just slides in.
English isnt my native language, and there isnt too much reloaders in my vicinity who can teach/share their knowledge with me, so I have to read a lot to get some info, and sometimes one run into bad piece of intel :)
If I get that kind of trouble, will it be enough to size the body with modified body die, and in separate operation, to size the neck?

As for trimming to 0.012, most of my cases have necks that have 0.013 to 0.017 neck thickness, and I want to have them uniformed, for achieving constant pressure on the bullet itself when seated. When I did some testing, I had pretty tight speed spread over the chrony (+ - 6 fps)
 
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will it be enough to size the body with modified body die, and in separate operation, to size the neck
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It should work.

A Redding body die, is about the same as your modified body die.
 
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