over pressure - sticky chamber /dies / rifle ??

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Keithjohn

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My fire formed case s (10) won't chamber easily or eject without a stiff bolt
These are once fired by this rifle ( Schultz and Larson low round count 6mm ) not over pressured
They fit so tight on the secon loading I pulled the bullets and measured OAL , shoulder with foster datum comparator , and whatever I could measure and can find no diff between the new case which chamber and once fired that will not after all sizing - neck and shoulder ?? Thes cases are in the junk bin for now .
It's a Lee collet die
I have a Redding shoulder die that I set back the shoulder 7 thou and still tight ( 3 cases )
This set up and rifle are new to me
Any suggestions ?
 
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long shoulder will cause chambering issues, but ejection should be normal if that's the only problem. Body taper... Redding makes a body die that only resizes the case body to SAAMI spec, leaving the neck untouched. Your "Redding shoulder die" must be something else... I am not aware that Redding makes a die to specifically set the shoulder back. Picture? Part number?
 
It is the body die .
I think I pushed the shoulder back with the collet die somehow , there seems to be a ridge by feel , I cannot measure it though , something to do with this long shoulder and my die settings I'm thinking
 
Buy a Forster full length benchrest die with its high mounted floating expander and ditch the Lee collet die.

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I use the collet die quite a bit with various cartridges and never experienced this. The brass was from factory ammo fired in your rifle or new component brass?
 
Mark up a case with a sharpie and confirm where it is binding. Do the same with a fired and unsized case, if you still have one. Privi brass is quite thick and hard, I've experienced similar problems in the past - the base of the case expands and binds in the chamber.
 
cosmic said:
Mark up a case with a sharpie and confirm where it is binding. Do the same with a fired and unsized case, if you still have one. Privi brass is quite thick and hard, I've experienced similar problems in the past - the base of the case expands and binds in the chamber.
Click to expand...

I tried the sharpie and can't see marks ( bad eyes ?)
Did a full length die then work for your brass ?
Did your bases expand after one firing ?
 
Put a line along the case body.. chamber with the line at 12 oclock... good or bad?

Rotate 90deg... chamber... good or bad?

rotate 90deg... chamber... etc.

Does the case enter the chamber well in one orientation but not in others?

Jerry
 
camster said:
Cases don't fit after sizing, but before seating a bullet?
Click to expand...

They don't fit after firing - and / or neck sizing or body sizing
All new dies so unproven but the fire formed cases don't fit back
I'll try Jerrys suggestion

I tryed a different powder at min load and it's much better but still a bit stiff bolt .
Could this S&L show pressure this low load 41 gr imr 4350 w/87 gr hornady
Maybe the bases are growing
I'm going to try 1 gr under min 40gr
 
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Also, check to see if you bumped the necks down creating a donut at top of the shoulder... if so, they should start easily, but be difficult or impossible to seat at the end of the forward bolt stroke.

Jerry is looking for a non-concentric chamber.
 
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Have you tried dropping an empty resized case into the chamber (i.e. muzzle pointed at floor) and closing the bolt? I wondering if your dealing with neck thickening from the resizing. Then again, I'm the first to admit, Jerry will forget more about these things more than I could ever hope to learn :)
 
hoytcanon said:
Also, check to see if you bumped the necks down creating a donut at top of the shoulder...

Jerry is looking for a non-concentric chamber.
Click to expand...

tinbird said:
Have you tried dropping an empty resized case into the chamber (i.e. muzzle pointed at floor) and closing the bolt? I wondering if your dealing with neck thickening from the resizing. Then again, I'm the first to admit, Jerry will forget more about these things more than I could ever hope to learn :)
Click to expand...

I thought I might have made a donut but the case doesn't chamber or eject right just after firing either . It gets better at LOW loads .
I will update
 
I had been working with a S&L in 7x61 that displayed nearly identical issue. In the end, finally found very rough interior of chamber where the case neck fits. Fired cases, even at start load levels were very difficult to extract; factory NORMA loads needed bolt handle "beat on" with heel of palm to get open. Full length sized cases would chamber to within about 1/16" and then get tight - bolt would not close. Along they way I discovered that the 7x61 dies were not sizing the case body all the way to the belt, neither would my 338 Win Mag dies, but my 458 Win Mag dies would. Then found I needed to slide a .005" feeler gauge into slot of shell holder, under the case, to get the shoulder back to where case would chamber. With bore scope, the throat was very smooth between start of lands and the case neck recess, but the case neck area was rough - dark (corroded?) triangular shaped "gouges" as if the reamer had been tearing out pieces instead of cutting the metal. I gained some ground by polishing neck by spinning a brass brush wrapped in steel wool (doused well with JB's) - owner eventually found someone in Saskatoon who pulled that barrel and somehow thoroughly polished the neck area on a lathe. Problem is apparently now resolved.
 
Potashminer said:
I had been working with a S&L in 7x61 that displayed nearly identical issue. In the end, finally found very rough interior of chamber where the case neck fits. Fired cases, even at start load levels were very difficult to extract; factory NORMA loads needed bolt handle "beat on" with heel of palm to get open. Full length sized cases would chamber to within about 1/16" and then get tight - bolt would not close. Along they way I discovered that the 7x61 dies were not sizing the case body all the way to the belt, neither would my 338 Win Mag dies, but my 458 Win Mag dies would. Then found I needed to slide a .005" feeler gauge into slot of shell holder, under the case, to get the shoulder back to where case would chamber. With bore scope, the throat was very smooth between start of lands and the case neck recess, but the case neck area was rough - dark (corroded?) triangular shaped "gouges" as if the reamer had been tearing out pieces instead of cutting the metal. I gained some ground by polishing neck by spinning a brass brush wrapped in steel wool (doused well with JB's) - owner eventually found someone in Saskatoon who pulled that barrel and somehow thoroughly polished the neck area on a lathe. Problem is apparently now resolved.
Click to expand...

Uuggg !
But , thank you
 
Do what Jerry said.

If there isn't a problem there, and you consistently have a problem chambering or ejecting - maybe too much pressure? If so you really need to find out why.

Check to see that both brass and chamber are CLEAN of any resizing waxes or lubes. Make sure the chamber is clean of any oil or solvent residue as well.

Make sure brass is not overlength - might need trimming.

If all else fails, I'd suggest full length resize (you need a full length resizing die which does this) of several brass which won't chamber, trim to length if necessary, and test each before reloading to see if it alleviates both chambering and extraction problems. Seat bullets in same without powder or primer and chamber check again to see if any portion of this process is creating donuts or case bulges.

Grasping at straws - Make sure bullets are not oversize for the bore, try some other brands.
 
If the chamber is not cut true with the bore then the neck of the fireformed case will only fit cleanly in one position.
I once had a M70 Winchester that came from the factory with a chamber that was not quite perfectly round, for some reason. Neck sized fireformed cases would not chamber cleanly. FL sized brass and new brass would chamber wonderfully.
 
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