Case resizing question for rifles.

zZ_denis

zZ_denis

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I recently bought 2000 .308 cases and decided to prepare them for loading (resize/deprime/clean/trim) before actually loading them. I went through about half of them(on a single stage press!) before deciding to load some rounds.

Once i did, i noticed that the rounds were hard to chamber. If i manually drop a round/case into the chamber, it goes in and out freely, but the bolt is significantly harder to lock.
On a bolt action rifle its annoying, but not a big issue. On semi-auto's (i've tried this on several different models) the bolt sometimes fails to close completely after the rifle is fired. Same rifles work perfectly with factory loaded ammo.

The dies im using are RCBS Full Length .308 dies, and i followed the instructions 100% when resizing.

Could it be due to defective/faulty die?
What should i do?
Thanks!
 
What rifles/brass are you using?? How did you set the die??You mentioned trimming.....what length did you bring it down to?

It could be a defective die or as simple as not sizing it enough to push the shoulder back.I'm new to rifle reloading so if we can get as much info on the table, the CGN collective will solve the problem.:)
 
Kind of depends which instructions you use - there's a lot of options with a F/L resizing die. Once in a while you run into cases that require the die to be screwed all the way down to contact the shellholder plus a bit more depending on the press and the chamber the cases came out of. (Trial and error, but I don't think I'd prep more than a couple cases before making sure they or the loaded rounds fit). Most gas guns don't even need F/L resizing once fireformed while some call for a small base die. Best starting point is probably a real good chamber cleaning with a bronze brush and some good crud remover. You'd be surprised how often even factory repairs to tight chamber problems come back as being "honed", translation being "buy a bloody chamber brush, dummy". If cleaning makes no difference and adjusting further down with the die doesn't help, you might do some careful measuring of the fired case diameters, especially at the web area, and compare to a factory loaded case. The semi might need the small base die to get them to cycle whereas in the bolt gun cases should nearly always fit with partial sizing, just enough to get past that bit of resistance level (unless of course they came out of a generous sized chamber). I don't shoot a semi, other than a 10/22, but none of my bolt guns require more than the slightest kiss on the shoulder of the case, often much less than that. A semi CF that won't close the bolt properly on cycling I think can be a not so good thing - isn't that the main cause of a slamfire? Good luck..
 
saskgunowner101 said:
What rifles/brass are you using?? How did you set the die??You mentioned trimming.....what length did you bring it down to?

It could be a defective die or as simple as not sizing it enough to push the shoulder back.I'm new to rifle reloading so if we can get as much info on the table, the CGN collective will solve the problem.:)
Click to expand...

I tried the rounds in Remington 700, Sako L579 and M14,2 different Valmets, all in .308. Brass used was once fired FC, RP, Norma.. Brand new brass (Lapua) chambers normally (without resizing)

Die is set according to instructions from RCBS, rechecked many times.
All brass is trimmed to 2.010"

What surprises me is that the cases/loaded rounds fall into the chamber freely, all the way (unlike non-sized OF brass), but the bolt/action is hard to close with a round in the chamber.
 
So they chamber before being sized and then after being sized/loaded it's a no go? Did you chamfer and debur the case in/out after trimming? (I'm not talking down, I just don't know how much experience you have reloading).

One crazy thought...do you have any 303 British size slugs around .311 that could have got mixed up? Or as mentioned...seated out too far?
 
What I've seen many many times before is although people follow the resize instructions to the letter they lose all reason when it comes to seating.
A rolled shoulder from an improperly set seating die creates the very problem that you are mentioning.

Worth a second look.
 
sbtennex said:
Kind of depends which instructions you use - there's a lot of options with a F/L resizing die. Once in a while you run into cases that require the die to be screwed all the way down to contact the shellholder plus a bit more depending on the press and the chamber the cases came out of. (Trial and error, but I don't think I'd prep more than a couple cases before making sure they or the loaded rounds fit). Most gas guns don't even need F/L resizing once fireformed while some call for a small base die. Best starting point is probably a real good chamber cleaning with a bronze brush and some good crud remover. You'd be surprised how often even factory repairs to tight chamber problems come back as being "honed", translation being "buy a bloody chamber brush, dummy". If cleaning makes no difference and adjusting further down with the die doesn't help, you might do some careful measuring of the fired case diameters, especially at the web area, and compare to a factory loaded case. The semi might need the small base die to get them to cycle whereas in the bolt gun cases should nearly always fit with partial sizing, just enough to get past that bit of resistance level (unless of course they came out of a generous sized chamber). I don't shoot a semi, other than a 10/22, but none of my bolt guns require more than the slightest kiss on the shoulder of the case, often much less than that. A semi CF that won't close the bolt properly on cycling I think can be a not so good thing - isn't that the main cause of a slamfire? Good luck..
Click to expand...

The instructions that came with the RCBS dies already ask to seat the die 1/8 to 1/4 turn further down, after the die touches the shellholder when its brought all the way up. I dont think seating it further down would make any difference as far as sizing goes. I would prefer to use F/L dies to make sure the rounds work in all of my .308 guns.

The chambers are as clean as new. Again, i am 99% sure that the problem is not with the guns or the guns that the o/f cases came from. What i will try tomorrow is measuring sized cases and comparing the measurements to new cases.


Longwalker said:
or...your bullets are seated too far out and are into the rifling.
Click to expand...
I measure the seating depth with a caliper on every single round i load. The bolt on the guns in hard to close even with empty sized cases (without bullet)

saskgunowner101 said:
So they chamber before being sized and then after being sized/loaded it's a no go? Did you chamfer and debur the case in/out after trimming? (I'm not talking down, I just don't know how much experience you have reloading).

One crazy thought...do you have any 303 British size slugs around .311 that could have got mixed up? Or as mentioned...seated out too far?
Click to expand...

Sized, o/f cases "fit" into the chamber easly, all the way in when inserted by hand, but the bolt is hard to close with a once fired, sized case already in the chamber. Brand new, never fired, NON-resized cases, as well as factory loaded ammo work just fine (as they should).

I am relatively new to reloading, so i follow all instructions 100%, so yes all the cases are chamfered and debured, and bullets are seated properly. And all cases are .308 :)
 
saskgunowner101 said:
I'm at a loss here....maybe DOUGLAS D is on to something here about the crimp. I have not used the crimp yet (backed out one turn and left there) so who knows. Good luck.
Click to expand...

Not the crimp but rather an improperly set seating die.
If you have your seating die too far down it will crush the shoulder.
RCBS should be case run to the top of its stroke,then die ran down to contact neck.
Then back off die and set retaining ring.
Then adjust seating depth using trial and error via the bullet seater only without moving the die body.
 
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zZ_denis said:
I tried the rounds in Remington 700, Sako L579 and M14,2 different Valmets, all in .308. Brass used was once fired FC, RP, Norma.. Brand new brass (Lapua) chambers normally (without resizing)

Die is set according to instructions from RCBS, rechecked many times.
All brass is trimmed to 2.010"

What surprises me is that the cases/loaded rounds fall into the chamber freely, all the way (unlike non-sized OF brass), but the bolt/action is hard to close with a round in the chamber.
Click to expand...

Ok I'm going to go in a different direction here, could it be that your extractor is having problems snapping over the rim, doyou have problems when feeding from the mag ??
 
Will a resized empty case chamber freely? If not, the seating die body is likely adjusted too far down, causing the case shoulder to roll. Check one of your problem loaded rounds carefully to see if the case body has a flared appearance at the shoulder.

If this is not the problem, you are probably seating your bullets too far out.
 
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Dropping a re-sized case into the chamber w/o closing the bolt tells you nothing meaningful as fall as correct case sizing is concerned.

When the bolt is closed on the re-sized case, the bolt will force the case shoulder towards making contact with the neck of the chamber.If you are getting significant resistance or crush when this happens(more than from the pressure exerted by a spring loaded plunger style ejector) you should conclude that the case is insufficiently re-sized.If you are starting with the bottom of the die in contact with the shellholder plus a 1/8 turn more with the press handle at full travel,turn the die body down in small increments and continue re-sizing and trial chambering with the bolt fully closed until the case chambers w/o resistance.You can also smoke the shoulder of the resized case and then visually check for evidence of contact with the chamber neck.There are variations among individual chambers and sizing dies,so while the die maker's instructions are correct,one must still determine the correct die adjustment for each individual chamber.

If you are excessively/overly re-sizing, the case shoulder should show evidence of distortion from the sizing die.

Verify and establish correct re-sizing length with an empty re-sized case before checking with a dummy or loaded cartridge(never a good idea) and confusing the matter further with issues of faulty crimp or excessively long bullet seating.After sorting out the resizing die you can then move on to examine crimp and bullet seating depth with the seater die.

Is your ejector frozen by chance? Check for free movement by depressing it with a punch before doing the closed bolt trial..
 
You might want to try Small Base Dies. I use SBD on all reloading with fired brass from semi- and full auto guns.

It is harder on the brass but it might solve your problem.
 
ive only seen this once but when i tried to do crimp + seating in 1 stroke it crimped and slightly deformed the neck of the case when seating the bullet. = wont chamber ..

from that point on all crimping was done after seating and never had a problem..

you could also get this if say your bullet was to far into the lands.
 
Listen carefully

"
douglas d said:
what i've seen many many times before is although people follow the resize instructions to the letter they lose all reason when it comes to seating.
A rolled shoulder from an improperly set seating die creates the very problem that you are mentioning.

Worth a second look.
Click to expand...
"
 
Re my earlier post.When you do the bolt closing test to determine if there is any resistance on a resized case it is a good idea to do this with a stripped bolt so that spring tension from the bolt does'nt give you a false sensation of resistance which may not be there.I have set my RCBS resizer for a number of .308s and a wide range of other cartridges in this way,incl a Rem 700 and an M14 which you have.

For the M700 removing the cocking piece/firing pin assembly will suffice.For an M14 type strip the entire bolt,incl ejector and extractor and close the bolt by hand with both the op rod spring and op rod removed.The Norinco M14 clones are notorious for long headspace so it is hard to understand why a FL resized case will not chamber freely w/o resistance.

I seriously doubt that all you will require a small base sizer die as a properly resized case in a conventional die will have it's radial dimension reduced at the bottom of the press stroke.You report this problem with a number of different rifles and there is no possibility that all of them have an undersize chamber.
 
Thanks to everyone for the replies. I am 100% sure that seating or crimping the bullet is NOT the problem. Since the problem occurs in many different .308 rifles, this rules out the possibility of the rifle being the problem.
This leaves only the case. Im starting to lean towards the "rolled shoulder".

purple said:
Dropping a re-sized case into the chamber w/o closing the bolt tells you nothing meaningful as fall as correct case sizing is concerned.

When the bolt is closed on the re-sized case, the bolt will force the case shoulder towards making contact with the neck of the chamber.If you are getting significant resistance or crush when this happens(more than from the pressure exerted by a spring loaded plunger style ejector) you should conclude that the case is insufficiently re-sized.If you are starting with the bottom of the die in contact with the shellholder plus a 1/8 turn more with the press handle at full travel,turn the die body down in small increments and continue re-sizing and trial chambering with the bolt fully closed until the case chambers w/o resistance.You can also smoke the shoulder of the resized case and then visually check for evidence of contact with the chamber neck.There are variations among individual chambers and sizing dies,so while the die maker's instructions are correct,one must still determine the correct die adjustment for each individual chamber.

If you are excessively/overly re-sizing, the case shoulder should show evidence of distortion from the sizing die.

Verify and establish correct re-sizing length with an empty re-sized case before checking with a dummy or loaded cartridge(never a good idea) and confusing the matter further with issues of faulty crimp or excessively long bullet seating.After sorting out the resizing die you can then move on to examine crimp and bullet seating depth with the seater die.

Is your ejector frozen by chance? Check for free movement by depressing it with a punch before doing the closed bolt trial..
Click to expand...

M14 is actually the easiest to close the action on, of all the rifles.

I will try your suggestions when i get home. One thing im a little confused about:
You suggest adjusting the sizing die further down, other posters in this thread suggest that the rolled shoulder is caused by the die being too far down. Seems like a contradiction to me.

Also, why would it make a difference how far down BELLOW the shell holder (at the top of the stroke) the sizing die sits? Once the shell holder touches the bottom of the die, case can not be pushed into the die any further. Wouldnt adjusting the sizing die too far down only cause the shell holder to contact the bottom of the die before the press is all the way up? Please explain.

Finally, will running the improperly sized cases (assuming this IS the problem) through the properly adjusted sizing die "fix" the cases?
 
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I believe what is meant (and not to contradict) is that your sizing die needs to be going down to either touch or almost touch the shellholder with ram up.You're probably there or close.

Now, it's the bullet seating/crimp die that might be too far down on the case shoulder. This is how I read it. I think this is what the other members are getting at.Maybe run the bullet seating/crimp die down until it just touches the case, and back it out a turn and see what happens. Load a dud without primer and powder.
 
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