Won't chamber after full size sizing

Tnslim

New member
Shooting a 6 Norma BR. I neck size for 5 firings, then clean, anneal, full length size and trim to length. Extremely hard to chamber and problem is a slight rising ring of approx .004" where body meets shoulder. Shouldn't the full length sizing take care of that. Dies are Forster. A new piece of brass chambers fine and neck sized chambers fine up to 5 firings. I follow the same regimen with all other calibers using Lee dies with no problems. Any ideas?
 
Since no one else is awake, I'd call Forester in the morning. There are lots of slight differences when it comes to 6MM BR. The original Remington 6BR is different from the 6BR Norma. A friend had a older Remington chamber, and had problems with new blue box Lapua brass not chambering. Sorry I'm no help.
 
Originally Posted By: Tnslim

Shooting a 6 Norma BR. I neck size for 5 firings, then clean, anneal, full length size and trim to length. Extremely hard to chamber and problem is a slight rising ring of approx .004" where body meets shoulder. Shouldn't the full length sizing take care of that. Dies are Forster. A new piece of brass chambers fine and neck sized chambers fine up to 5 firings. I follow the same regimen with all other calibers using Lee dies with no problems. Any ideas?




Good morning (at 4:30 AM
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You didn't say which Forster die you were using to "Full length size".

That is important.

If you are using the Bump die, the little ring is normal - when you chamber the case, does the little ring get shinny from rubbing the chamber (that would be normal too).

If you are using the regular FL die, and have the FL die all the way down, enough that there is cam-over, then your chamber might be a few thousandths short(er), or the die might be a few thousandths long(er) - (not unusual because of normal machining tolerances).

When you "Bump" a case, the body does not touch the die, so the 0.004" ring is a normal "muffin top" because of the unsupported case walls.
When you FL a case, the body gets "squoze" first, and so the shoulders move forward a few thousandths - then at the very end of the stroke, the shoulder gets pushed back and all is fine.

But with a short cut chamber, or long cut die (both can still be "In spec") the shoulder is not pushed back far enough.

I had a similar problem with my 6mmBR. When you fire the tight case, all should be fine.

 
Originally Posted By: larrAre you chambering the brass with a bullet seated or just the brass with no bullet seated?

Both. Neither will chamber without force. New brass chambers fine.
 
Originally Posted By: FurhunterIf neck sizing is working then I would continue it and don't bother with the FL sizing after annealing.

After around 5 firings the rounds get hard to chamber. My opinion is when neck sizing the neck gets pushed back into the shoulder creating the ring but the FL die won't remove the ring.
 
Originally Posted By: CatShooterOriginally Posted By: Tnslim






Good morning (at 4:30 AM
frown.gif
)

You didn't say which Forster die you were using to "Full length size".

That is important.

If you are using the Bump die, the little ring is normal - when you chamber the case, does the little ring get shinny from rubbing the chamber (that would be normal too).

If you are using the regular FL die, and have the FL die all the way down, enough that there is cam-over, then your chamber might be a few thousandths short(er), or the die might be a few thousandths long(er) - (not unusual because of normal machining tolerances).

When you "Bump" a case, the body does not touch the die, so the 0.004" ring is a normal "muffin top" because of the unsupported case walls.
When you FL a case, the body gets "squoze" first, and so the shoulders move forward a few thousandths - then at the very end of the stroke, the shoulder gets pushed back and all is fine.

But with a short cut chamber, or long cut die (both can still be "In spec") the shoulder is not pushed back far enough.

I had a similar problem with my 6mmBR. When you fire the tight case, all should be fine.



I'm using the full length die, not the body die. If I fire one of the FL sized rounds( if I can get it to chamber) it takes an act of congress to get the bolt back to eject.
I've came up with an idea to remove the ring and that is to chuck it into a drill press and carefully use a fine file to remove the ring. Would that compromise the brass? I'd only need to remove around .002".
 
Have you measured the OAL of the cartridge after firing. Maybe you are bumping a long ctg. I had some 22-250 once, that had gotten too long and had to trim to length prior to FL sizing, then it would chamber. That brass has to go somewhere when the cartridge stretches.
 
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Good point and no I haven't measured length after firing. I did FL size a new piece and it chambered fine but of course it hadn't been blown out by firing.
 
Originally Posted By: CatShooter
When you FL a case, the body gets "squoze" first, and so the shoulders move forward a few thousandths - then at the very end of the stroke, the shoulder gets pushed back and all is fine.

But with a short cut chamber, or long cut die (both can still be "In spec") the shoulder is not pushed back far enough.



That's my guess.
Your case is getting "squoze" and made longer, and then the shoulder isn't getting pushed back enough, or maybe not at all.
A bump gauge would let you know for sure.
 
Originally Posted By: TnslimOriginally Posted By: Furhunter
If neck sizing is working then I would continue it and don't bother with the FL sizing after annealing.



After around 5 firings the rounds get hard to chamber.
My opinion is when neck sizing the neck gets pushed back into the shoulder creating the ring but the FL die won't remove the ring.



Neck sizing CANNOT cannot push the shoulder back, unless there is some other problem.

You did not answer - when you FL size and then chamber, does the 0.004" ring get a shinny edge to it?

This whole thing does not make sense - My 6mmBR cases never need FL sizing and I have lost count of how many firings the brass has gone through.

Who did the barrel/chamber?
 
Are these neck turned cases?

Do you have a picture of this shiny ring?

Is it at the body/shoulder or is it at the shoulder/neck area?
 
Originally Posted By: Furhunter
Are these neck turned cases?

Do you have a picture of this shiny ring?

Is it at the body/shoulder or is it at the shoulder/neck area?



Original post said body/shoulder - it is a muffin topped case
 
Originally Posted By: Tnslim

I'm using the full length die, not the body die. If I fire one of the FL sized rounds( if I can get it to chamber) it takes an act of congress to get the bolt back to eject.
I've came up with an idea to remove the ring and that is to chuck it into a drill press and carefully use a fine file to remove the ring. Would that compromise the brass? I'd only need to remove around .002".



Forster does not make a body die... they make a FL die and a shoulder (only) sizing die (called a bump die).

If you file off 0.002", then the next time you FL size the case, you will be back where you started and have to file the case again - and soon, there will be two pieces of the case
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The ring doesn't have any shiny to it. The barrel is a Criterion 28" 8 twist bull and is a mighty fine shooter. The dies are Forester full length, neck and seater dies. I follow the same regimen with all my other calibers using Lee dies and never have a problem. I've got some Remington 22-250 brass with over 25 firings and still good to go. I've got around 45 pieces of new brass that maybe I'll just neck size only and see how they do. I haven't turned the necks on any brass.
 
Originally Posted By: TnslimShooting a 6 Norma BR. I neck size for 5 firings, then clean, anneal, full length size and trim to length. Extremely hard to chamber and problem is a slight rising ring of approx .004" where body meets shoulder. Shouldn't the full length sizing take care of that. Dies are Forster. A new piece of brass chambers fine and neck sized chambers fine up to 5 firings. I follow the same regimen with all other calibers using Lee dies with no problems. Any ideas?




I think your chamber is closer to max and your die is closer to min length on spec.

I would back your FL die off a full turn. Size a 5 times fired case and chamber it. If it is still tight I would turn the die down in small increments like 1/64 turns. Sizing and chambering each time until the case just chambers easy. I bet you find the ring will not appear at that point either.
 
Originally Posted By: SmokelessOriginally Posted By: TnslimShooting a 6 Norma BR. I neck size for 5 firings, then clean, anneal, full length size and trim to length. Extremely hard to chamber and problem is a slight rising ring of approx .004" where body meets shoulder. Shouldn't the full length sizing take care of that. Dies are Forster. A new piece of brass chambers fine and neck sized chambers fine up to 5 firings. I follow the same regimen with all other calibers using Lee dies with no problems. Any ideas?





I think your chamber is closer to max and your die is closer to min length on spec.

I would back your FL die off a full turn. Size a 5 times fired case and chamber it. If it is still tight I would turn the die down in small increments like 1/64 turns. Sizing and chambering each time until the case just chambers easy. I bet you find the ring will not appear at that point either.


When you do this take out the expander button so you do not over work the neck. When the brass will chamber then put the expander button back in the die and just run the expander button in and out of the mouth of the brass.
 
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