Primers Ejecting?

I noticed something in this picture:

4667193209_a0653d18b5_b.jpg


Note the 'ring' on the case at upper right. That looks like the chamber is too tight, or maybe dirty?

The neck of the case has been 'swaged' by the bullet passing through too tight of a chamber/throat???

Do most/all of the ones whose primers ejected show that problem? If so, that would explain the lack of bolt lift - AND the different case profiles. The 'neck pinched' ones will be headspacing on the neck - as they SHOULDN'T; the non-pinched ones headspaced on the belt, as normal.

Does the shoe fit on that one? Definitely take some chamber measurements - I see you have a lathe there; PM me if you'd like tips on making a chamber throat gauge.

-M
 
Yeah, I'm already trying to dream up things to make on the lathe for the rifle... that might be the first thing I end up making... as soon as I finish making things for my truck this weekend. It's been in the middle of a frame-off resto for the better part of a year, and it's time to get it on the road.

As for the neck, those are the factory crimp markings... at least I think those are what you're referring to. I think tomorrow I'll throw the two remaining cartridges from that box onto the scale and see what they come in at as compared to a cartridge from the second box I have yet to use. That should tell me if its a case of overloaded factory ammo. If it's not, then... well... the game's afoot for real, I suppose. At least I bought this rifle as a starting point for a project (new barrel, rebuilt/formed stock, etc etc) so it won't be too heartbreaking if I end up having to rework things extensively. I'll also fire Winchester an email tomorrow, just to see what they have to say.

Any other ideas?

EDIT: Thanks for all those who've been replying here, I am grateful for the feedback. I know I'm far from as knowledgeable about this stuff as some/most of you folks, but I appreciate the crash course in problem diagnosis!
 
Even if they're the factory crimp marks, the uneven way they appear now says to me "Danger, Will Robinson!" (as I wave my arms and blink a light on my chest).

-M
 
Get in touch with the ammo company, don't use the rest from that box. :eek:

I'd like to hear what they have to say about this.
 
I agree with Doc M, looks like the chamber is too short for the neck length and the crimping action on the shank of the bullet raised the pressure beyond safe limits. I wouldn't be concerned about a slight difference in shoulder shape as the case has just mirrored the chamber wall. The short neck is an issue though, and I would opine you have a rifle problem rather than an ammo problem. There is nothing about the case heads of the fired rounds that lead me to believe there is a problem with the bolt face itself.

Very interesting problem, thanks for the pics. I've seen rifles, both factory and custom, that had issues with the way the chamber was cut, but this is the first time I've seen it result in pressure issues. Its almost as if the chamber was cut for .308 Norma instead of .300 Winchester.
 
Ive had a primer come out before....of course it was only after I managed to open the bolt and eject the case which took considerable effort.

Takes a hell of a lot of pressure to open up the pocket and have the primer flop out or Im wondering if there is so much headspace that the primer has nowhere to stop ?
 
Diffenatly some good pressure there. don't shoot any more of those rounds. Try a new box of factory. Not the same lot no. If your other box is the same lot get another. Chamber length is easy, Trim some brass extra short and fire with a factory duplication load.
 
Have you contacted Winchester yet? That's a safety concern more than anything now isn't it?

One would think after the 1st or 2nd ejected primer on factory ammo you'd stop using it and call the manufacturer immediately.
 
ammo lot #?

Hi dfritter,

i just purchased a ruger M77 in 300 win mag and am just about ready to visit wally world for some win super x 180 gr. ammo.

this thread has fascinated me.......... could you post what the lot # of the ammo you got is so that i might avoid that??

thanks, and good luck!!!
 
It is not an ammo problem! Sounds more like wrong ammo used in wrong gun.

Have any of you ever seen primers pop out with factory ammo???? Ever??? Anyone?????
 
I was shooting the 150s, so you should be fine... I'm leaving the whole thing alone today but I'll pick up a headspace gauge set this weekend, just to rule that possibility out (or in).
 
dfritter1 said:
But, differing shoulder profiles...

4667193535_49639bf8d8_b.jpg
Click to expand...


I find that very strange that the one that spat out the primer (left ??) has a less defined shoulder than the other. If anything I would have expected the opposite.

I wouldn't bother with the headspace gauge, that is the furthest thing that will cause excess pressure like the cases are showing.
 
I think the pressure is so high the chamber and case expanded to produce the less pronounced shoulder. I bet if you run it through a resizing die it will be very tight and possibly extra long from brass thinning.
 
Toomanyguns said:
More likely to be an internet hoax.:eek: Lots of that in the world these days.
Click to expand...

You should inquire about a discount in tinfoil at your local grocer, what with all the hats you must be making! I kid, I kid...

In all seriousness though, I am not making this up, although I wish I was. You're welcome to take a look for yourself if you're in the lower mainland, though!

I would run it through a press to see what a case comes out at after re-sizing, but I haven't assembled my press yet (bought it at the Wholesale grand opening in Langley) as I don't have room on my workbench for it until I finish rebuilding my truck's motor. I've only got one buddy that shoots, and he doesn't have a press either, so I guess I'll just have to wait. In the meantime, I figure a set of headspace gauges is probably a worthwhile investment, as I will eventually be buying a Shilen barrel for this rifle anyway.

Also, I forgot to mention that PM'ed the previous owner to see if he'd had any issues with the rifle prior to selling. I know I have to take his response with a grain of salt, but I figure it might be somewhat helping in figuring out if this was a conditional thing, or an equipment thing.
 
On the brass being too long, I've found that ALL factory once fired brass from my stevens 200 300WM, was beyond the max length and needed trimming before the first reloading. I trim down to the trim to length in my manual, and most of the factory crimp is gone from the top of the mouth. So, it's been my experience, that Winchester brass is on the long side, combine that with a short chamber, and stuff happens.
 
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