unusual problem with 308 brass

[m657]

preparing load up some range fodder for a Ruger Scout rifle, and getting various supplies together....

Haven't loaded 308 for about 10 years but have some old brass I'm sorting thru....

came across a little stash of about 20 loaded mixed-brass cartridges in a box/baggie marked "won't chamber"....

Having a little time I started pawing thru them to see...and yes, the WON'T chamber.

Observations:

1) All fit in the standard Wilson case gauge properly for OAL size;

2) all but a few are 2.800 OAL with 150 gr bullets;

3) all but a few are brass trim length 2.005";

4) no obvious defects of configuration, other than a couple are probably long enough so the bullet may run into the lands of the rifle barrel;

5) some of them will chamber but the bolt will not turn into lock position;



6) I disassembled a few of them, and even with the unfired yet-sized case empty will not fit so bolt locks properly

Of course I'm not forcing anything. And the case still fits the case gauge.

Some of these are remnants of my old LC case-mouth-only sized for a precision chamber....always closer dimensions than standard chamber....so IF those were the ones, they should already be 'small enough' to fit, no?

So far the answer to this eludes me.

What could account for a sized (previously fired) case with no round inserted, that fits a case gauge, NOT chamber in a new Ruger Scout?

And yes, they all say '308'. I do have some with the box (once fired) say "for AR 7.62" but those I haven't even got to yet.

I'll be working on this issue tomorrow, but wonder tonight just "WHAT" is the problem here.......


UPDATE 2/6:

OK.....have pulled all the components apart;
all but one bullet was 150g RNL

All cases fit Wilson case gauge;
All cases are trimmed to 2.005-2.007;
NONE of the cases fit new Scout Chamber;
ALL were previously used in tight match grade chamber of XP-100 custom barrel;
All cases were either LC, Winchester or R-P previously loaded/reloaded by me;

Inspected & reset my RCBS hardly used 4 die set;
Set die to touch shell plate;
Re length sized 1st case; bolt will not close handle down;
repeated on 2 more cases; same deal.

Started screwing expander plug adj. downward, no difference.

Repeated several times moving plug downward as that's the only remaining movable die component; managed to evenutally get a small mark around the shoulder/case body right at the bend.

All cases still fit Wilson case gauge.

There's only about 25 or so cases involved and all appeared to have been reloaded at least 'several' times....have not arrived at diagnosis OR evaluation of 'next step'.

Next session I'm going to load a few cases that DO chamber just to make sure all that end is right.

 

[arjay]

Id run one through a full length sizing die,measure the length and trim if necessary and see if it chambers to start with.

 

[kwselke]

What arjay said, but I'll add pull the bullet and dump the powder before resizing.

 

[chipking]

+1 on full length sizing. Neck sizing will not push the shoulder back to the correct length which means that if they were fired in a rifle with max or excessive headspace ( in 308/ 7.62x51 that is measured from the rear of the case to midpoint on the shoulder) they will not chamber in a rifle with min headspace. The first clue is that you cannot chamber the empty sized round.
Chip King

 

[arjay]

What arjay said, but I'll add pull the bullet and dump the powder before resizing.

well sure,if ya wanna do it the easy way lol

 

[m657]

Thanks, I'll report back after the next step....

 

[Neumann]

Full length resizing of a bottle necked cartridge is done to the shoulder length. Unlike straight pistol cases, the rifle die is not set to touch the shell plate, but usually a significant distance above it. You need a gauge which measures the base to shoulder length. There's no easy way to measure it directly. OAL is easy enough to measure using calipers. (Trim to length after resizing).

Some rifles have a short throat, so that some bullets will engage the rifling even if the OAL is within specs.

Neck sizing only works if you shoot it in the same rifle as the first time. The gauge will also check the diameter. You may need to use a small base die for semi-auto rifles to get rid of any bulge near the base.

 

[Nevada Ed]

The shoulder has probably moved forward or is over size at the rear of the case neck.

A full resize should fix the problem where the bolt will close with minimum pressure with the correct size case.

Good luck.

 

[Engineer1911]

Rifle die set-up from RCBS

RCBS - Precisioneered Shooting Products - Step-By-Step Reloading#

See step #5, directions clearly state that sizer die is supposed to contact the shell holder. This may be the cause of your problem.

I have had .308 Win brass that fits a Wilson case cage, but required significant bolt force to close. After firing, bolt handle lifted easily. Happened with just one 20 round box of reloads. Reset sizer die per link above and no more problems.

 

[scooter123]

As note you need to do a full length size to "set" the shoulder back a bit. If you get once fired range pick ups that were fired in a NATO chamber the shoulders can require enough work to cause minor buckles. The solution for that is to size in 3 or 4 stages. BTW, If the buckles aren't severe I see no problem with Fire Forming the brass to remove those buckles. Done it many times without any hint of harm.

However, there is a flip side to that full length sizing operation. If you set the shoulders back more than necessary you WILL increase the case stretch during firing, which will shorten the life of the case. I have a Wilson case gage but I use my Ruger as the final check when setting up my full length sizing dies. My procedure is to set the full length sizing die to the point where the bolt throw with an empty case on the rifle lightens up to about 90% of the effort of closing the bolt on an empty chamber. Ideally what you want is the shoulders are fully in contact in the chamber when the bolt is closed without any air space at either shoulder or case head. Do that and you'll see almost no increase it case length from firing. The downside to doing this is that it does take more time to set up and you need to check a fairly large percentage of your sized cases to insure that those on the "plus" side out of your sizing operation won't have too heavy a bolt throw. Yeah, the sized cases will vary a bit.

 

[David Sinko]

I ran into the same problem not long ago. It turned out that my full length sizing die had not been screwed down far enough. I must've done something with it and then not turned it down to the proper depth, which is touching the shellholder when there is a case in the shellholder being resized. I full length resize everything for all my .308 rifles. I don't think I've ever neck sized so much as a single piece of brass. I'm still using some brass that has been shot out of M1A, FAL, AR-10 and now SCAR17 rifles and it's still serviceable.

Dave Sinko

 

[fredj338]

It only takes the shoulder misplaced by 0.002" to not chamber. So maybe the Ruger has a shorter, min spec chamber? As suggested, I would FL size & see if that case fits. FL sizing only increases headspace if the chamber is sloppy. If it is min spec, the FL sized roudn fits, then you get minimal case stretching.

 

[OldAFVet]

I had much the same issue with my .223 rifle cases--stiff on closing the bolt. Tweaked the FL die 1/8 turn and problem solved. I guess it had been reset for the T/C .223 barrel I once had.

 

[m657]

note update on 1st post....

die is set as far down to shell plate as possible

pending some sudden insight maybe I'll have to 'repurpose' the lot...

And while I don't think I can actually visualize .002" difference, sitting side by side with brass that does work in the chamber, I can see nothing different.

No buckles or brass distortions visible. And I can't wiggle anything in the case gauge enough to think there's any loose fit.

continues as mysterious....

 

[scooter123]

If you have a friend with a machine shop or access to one you can take just a few thousandths off the lower face of the sizing die. This will allow you to set the shoulder back just a bit more. You might also consider purchasing a Dillon FL Sizing Die. My 308 die set is Dillon and the full length die will allow me to to set the shoulders back further than ideal for my rifle. BTW, that is were I learned that setting the shoulders back too far leads to excess case stretch. The first batch of 308's I loaded up grew between 0.007 and 0.012 inch on firing. Now I have the lock ring set where I can feel a small increase in the drag on bolt closing with about 5-7% if the cases having a bolt throw that is just a bit on the heavy side. As for case stretch, it's now running between 0.0 and about 0.004 inch per firing cycle.

I also fire form and neck size to the greatest extent possible because the neck sized cases don't grow at all. However, after several firing cycles the bolt can start to get rather heavy on some cases so any "tight" cases get separated out for a full length size.

 

[bentcam]

something to give a try, remove the expander/primer punch from the die and size a known bad case. the punch set a little deep can prevent case from getting full into die, the expander can pull the neck and move shoulder.

 

[beerbelly]

Just curious (unless I missed it)....does factory .308 0r 7.62 chamber in your Ruger ok?
beerbelly

 

[growr]

I always full length re-size all of my .308 brass in addition to using a case gauge, I also use an RCBS Case micrometer to make SURE that the should is set back to the exact position.

This especially important in lever guns and semi auto's.....M1A's CAN(but rarely) fire out of battery due to shoulders not set back properly. The results of such are dramatic and disasterous!!

Randy

PS. Glen's article on reloading for the M1A is outstanding and should be a must read for anyone using one.

 

[boatbum101]

Unless I misread OP's original post he did FL resize the cases . If this is a new or new to him rifle he's never shot , I'd be checking headspace with a GO gauge . It's possible chamber was never finish reamed . A FL size die screw in to touch shellholder should be sizing the cases to min dimensions .

 

[m657]

Thanks for all the ideas here gents.

re: " His thinking that once common cases have too soft from reloading to use, it is not worth the time and effort to mess with them."

This is sounding better all the time....

Given I've never been much of a rifle guy, there are tools/methods beyond my experience mentioned.

This is a NIB Ruger Scout Rifle bolt action, basic M77 model standard unfired 308.

After reviewing this thread numerous times, I've noticed all these affected cases are in fact older and reloaded unknown number of cycles. Granted most (ALL the LC cases for instance) had a previous life decades back in my IHMSA custom XP-100 FL308 hand gun. Reloading in that tight match quality chamber was 'neck size only' for the years I used it.

I shot Cowboy Matches for over 15 years & am familiar with straight wall pistol caliber cases, the kind Gawd intended when She invented Shot & Shell....but these bottle neck long barrel things have their own needs.....

It had never occurred to me that yes, rifle brass really CAN have a 'useful life span' that I may have simply exceeded.

Thanks again for the thoughtful responses here.

....I have a special storage area for this kind of brass issue.....now that my mind has cleared.....