30-06 fired brass. Is this normal?

[SWThomas]

I'm just curious because my 308 brass doesn't do this. See the ring towards the head of the case? Is that normal? These were fired from a bolt gun with a chamber cut with a PTG Serengeti reamer. This is once fired Win brass that has not been resized yet. I checked the inside of the case with a paper clip and couldn't feel anything.

 

[jonbearman]

I don't know the specs of the Serengeti reamer but it looks slightly looser which will cause the expansion line you are seeing. It will lessen case life however with minimal sizing it will help without working that area too much. A lot of older rifle's will do this as well as military rifle's with looser chambers for positive extraction and the ability to work with dirt and grit in them during battle.

 

[bigedp51]

The base diameter just above the extractor groove should be approximately .470 and American made brass runs on the small side.

Measure the base diameter just above the extractor groove and at the maximum area of radial expanshion, this will tell you if you have skinny brass or a fat chamber.

At the link below is a drawing for the PTG Serengeti reamer, the print shows a base diameter of .474, so you might have both, small diameter brass and a large base diameter chamber.

The Logical .30-06
by Germán A. Salazar

http://riflemansjournal.blogspot.com/2009/11/cartridges-logical-30-06.html

The cases below were fired in the same rifle, the Greek HXP cases have a smaller base diameter than the Prvi Partizan. The HXP cases are good for many reloads as long as the case is not over resized at the base.

 

[expiper]

OP,,,most new unfired 06' ctgs are ~.464 at the .200 line,,,my reamer is .467" at that point and is plenty big,,works perfectly with Redding type S full length dies,,,measure yours ,,,if it is as big as the drawing provided your primer pockets will not last long,,,and resizing will require a lot of lube and force,,,Roger

 

[SWThomas]

The brass is 0.464 right above the lip and 0.469 where the ring is. I measure a fired case and measured the reamer and all the dimensions appear to match.

 

[vtmarmot]

A friend had two case head separations in a Garand match the other day. Not many loads on the brass but he was using a small base die. On brass that had not separated I could see the dished in ring like the pictures and a bright ring just above that where the stretching (and later separating) occurred. With a chamber evidently that generous I would bet he could get away with a regular sizing die. Or, I suppose it could have been undersized brass.

 

[Lapua40X]

I have the same "stretch marks" (although not quite as pronounced) on my '06 Winchester brass. My factory barreled (circa 1942) 1903 Springfield once fired cases measure .464 just above the extractor groove and .467 at the most forward point of the "stretch marks". Compared to unfired brass from the same lot, that's .0005 growth at the extractor grove and .004 growth at the stretch mark.
Haven't found any real reason to worry about it though.

 

[cmillard]

i too get the same marks out of my 1903-a4 springfield--mine has a criterion match barrel. I don't get too worried about it.

 

[SWThomas]

Thanks fellas. That eases my mind a bit. I'll keep an eye on it.

 

[snert]

I saw the same on my Rem 700

 

[SWThomas]

OP,,,most new unfired 06' ctgs are ~.464 at the .200 line,,,my reamer is .467" at that point and is plenty big,,works perfectly with Redding type S full length dies,,,measure yours ,,,if it is as big as the drawing provided your primer pockets will not last long,,,and resizing will require a lot of lube and force,,,Roger

Just to clarify, you're talking about the Type S bushing die? I have one of Redding's standard FL sizing dies, but I don't think I'm gonna get the most accurate ammo using it unless I turn necks. Being that all the brass I've got have different neck thickness (Lapua, Win, Rem, Fed), I'll be getting varying neck tension using this fixed die. Have you run into any concentricity issues using the bushing dies?