Gunsmithing Case Marks Help

[trappedinmd]

Hello,
I am curious if the marks on my (winchester factory) fired .30-06 cases are normal. I am uneasy with the "step" that forms right at .245" inches up from the bottom of the case. The "step" is big enough to feel with your fingernail and only encompasses about two thirds to three quarts of the circumference. I am worried that there might be excessive head space causing this. I stuck clear packing tape to the bottom of a new round and cut off the excess. On the new factory ammo I could still close the bolt after 3 layers of tape, but it would not close with 4. With a piece of once fired brass i could close the bolt with one layer of tape but not with two. If it is related to excessive head space I think i should be able to adjust It as the gun (remington 783) uses a barrel nut exactly like a savage. Tell me what you guys think please!!

Regards,

Trapped

 

[HodgdonExtreme]

Not a headspace issue, but rather, a loosie goosie chamber artifact.

A problem? Probably not.

To check, slice a case in half the long way, so the cut goes right through the middle of the "buldge". If there is obvious casewall thinning at the bulge, that's bad. If not, no problem.

Lapua/Norma/European brass will probably lessen the effect.

Edit to add: It's bad if your sizing die removes the bulge. That'll work/thin/fatigue the brass.

 

[trappedinmd]

Thanks for the input!

 

[CNJarvis]

Not a headspace issue, but rather, a loosie goosie chamber artifact.

A problem? Probably not.

To check, slice a case in half the long way, so the cut goes right through the middle of the "buldge". If there is obvious casewall thinning at the bulge, that's bad. If not, no problem.

Lapua/Norma/European brass will probably lessen the effect.

Edit to add: It's bad if your sizing die removes the bulge. That'll work/thin/fatigue the brass.

This. I have a 270 Win that does the same thing. I have 5+ firings on some cases with no issues. I will add that I neck size my brass.

 

[jsthntn247]

If you can fit 3 pieces of tape on it and it has a nut, I would loosen the barrel and tighten it down some. One piece of tape on a new piece of brass is what you are looking for. You will have to use that type of brass from then on out though or make sure the brass you get has a similar headspace. That does look like a fat chamber too.

 

[Straight Shooter]

I doubt it is a fat chamber. What you have there is classic undersized Winchester brass. That is why your full length die will not iron it out. It's already too small to begin with and your full length die will only size it back to factory spec which is much larger than that brass. No need to do anything or you can try another brand of brass.

 

[SporterII]

I am glad to see this thread.
You have there the 'bulge'.
Small brass and probably a good SAMMI spec chamber.
My 7-08 did it. My 280 does it.
Measure the virgin brass at that point [.200 above the base], Look at a sammi print, measure a fired case, and you will have your answer. Brass is made small to fit 'any' chamber rusty, dirty or close spec.
I doubt its a fat chamber as well though, that's possible.
eta; your reamer, your brass.... different story.
Run it.

 

[hdbiker1]

I noticed the same thing with the Winchester brass in .308. I measured the brass and compared it to Lapua and others, only to find out that Winchester makes their cases smaller at the web and rim.

Btw, this started with hard bolt lock up with cases other than Winchester, which locked up easily in a Remington 700. Come to find out my extractor was screwed. The extractor chewed up the rims as it tried to ride over it. Tuning it didn't help. Replacing it did.