Strange problems

C

cranelake

Guest
Hi guys,
I experienced a strange problem when making new brass for my 6PPC, .262 neck.
I ran a bunch of 220 russians through a Redding Small Base FL die to locate the new shoulder place and then expanded the neck and turned it to measure .260 with a bullet. I sized the case once more with .258 bushing, primed the case, dropped V133 up to beginning of the neck, seated a bullet, put some oil on the cases and fireformed it.
After fire forming the bolt was easy to open and the lenght of the case was 1.493 or so.
When FL sizing the cases again I had to turn the die all the way down to touch the shell holder to get the brass to chamber again.
I reloaded the cases again with 28.3gr V133 and shot them again. The bolt opened up easily, no stickyness. Cases were still 1.493 or so in lenght.

Now, if I try to chamber the cases there's no way they would chamber. When I try to FL resize them with my small base die it's no help. The cases will not chamber even if the die is screwed all the way down to touch the shell holder. I've measured the change in headspace with a small gauge(harrell) and it looks like the headspace does not change when I try to resize it.

The necks of the fired cases measure .261 in dia.

Have something gone wrong with the fireforming? All I can think of is the shoulder has not jumped enough forward during the initial fireform and on the secons shot the case grew in lenght near the web since it already made contact at some part of the shoulder???
There is a shiny ring on the brass above the web but I'm not sure if it's from the die or the result of case growth.

Have enyone else experienced this and what is the cure or should I just repeat the whole thing and hope for better results?

Thanks.
 
Take measurements...

After firing the case, measure the overall length, diameter at the neck, diameter at the shoulder, and diameter at the web...Document those dimensions...
Remove the firing pin from your bolt and try to chamber the fired UNSIZED case..do not size it yet..!
If it goes back in the chamber with no problems, then you are most likely bumping your shoulder back too far and causing a buldge at the shoulder...
To verify... SIZE that fired case (you just measured and put back in the chamber) NOW that you have sized it..measure the neck, shoulder, and web dimensions...You will probably find that you have caused the shoulder diameter to increase by more than .005"....
What kind if die are you using..?
Back it out until you can just chamber the case with some light resistance while closing the bolt....don't worry about neck sizing length until you have the body sizing, and shoulder bumping correct...

If this doesn't work...take the rifle, cases and dies to a Gunsmith...
 
?

Crane,
Who told you to use a small base die to push the shoulder back, size the cases with a .258 bushing and put OIL on the cases ? STOP doing whatever you are doing and get some experienced FIRST HAND HELP ! Whoever your gunsmith is or whoever made your neck turner would be a good place to start. Be carefull,be safe,be shure !
joel
 
I should've been more clear with this.

-Again, I used the Redding Small Base FL die to locate the neck/shoulder junction place for 6PPC, since it's in different place that it is on the parent 220Russian.
The die mkaes a fine ring on the shoulder area and I've always turned with my Sinclair turner to just "kiss" the shoulder so that the thin ring is removed and replaced by wider shiny area. I do this to avoid the "donut".
-Then I did my normal neck turning. After turning I did resize again to get the grip on the bullet.
-ON the loaded round I did put some oil to prevent jammin in the chamber during fire forming.

Is there really something wrong with my case prep prosedure?

I did all the measurements suggested:
When the fired case is resized only a minimum amount, just able to remove the primer, the headspace & web don't change, but the shoulder dia reduces 0.002in. Now if I make the check with bolt (firing pin/spring assy removed) the bolt will not close easily. I would have to force it down, whioch I do not want to do.
From here on, even if I screw the die in until it touches the shell holder, nothing seem to change. Not even the headspace and the bolt is hard to close.

This is a bit older gun and barrel I bought to serve as a fireforming rig. I'll just re-chamber it. I just wanted to give it a try.

Thanks again.
 
You would have to do a chamber cast to know the dimensions of the chamber.

Part 2. Expecting brass fireformed in an unknown chamber to fit some other chamber is a tremendous leap of faith.
 
There have been rare instances when I have had to grind a few thousandths from the top of a shell holder to allow a size die to go down enough to even touch the shoulder on the case in question, when the ram was all the way up.

This may be the answer here, or not.........
Cheers,
Jim
 
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