Bulge in 30-06 brass

[pyrolater]

I have a 1956 vintage Winchester model 70 in 30-06. I shot some Federal 150 grain ammo and some Winchester 150 grain ammo through it. I wanted to reload the brass for the Model 70 and for highpower in my M1 so I tumbled, polished, sized trimmed and all that. When I was getting ready to actually put powder and a bullet in the brass I noticed a slight bulge at the bottom of the case. If any one is familiar with the bulge you get with 40 S&W the bulge on the 30-06 brass is pretty similar.

It looks like all the brass shot out of that rifle has that little bulge. If you have a nice clean case and hold it under a desk lamp and turn the brass in your hand you can see the case is just slightly deformed mostly on one side or about a third the way around just above or right even with the web.

My question is: what the heck would cause that?

I have no signs of over pressure. The rifle came to me used but looks like it has not been shot very much. I get about an inch and a quarter or so groups with it.

I really wanted to reload the brass that went through that rifle but I’m afraid if I reload brass with a bulge in it the brass has already been weakened and If I make up a nice concentric round as soon as I stuff on in the chamber the round will be out of alignment.

Any suggestions?

 

[NCsmitty]

Pictures of the brass? Have you inspected the chamber for any irregularities?


Ncsmitty

 

[alsaqr]

The barrels of the older Winchester model 70 rifles have a coned breech like the model 1903 Springfield and the model 1917 Enfield. When the bolt is closed the rear 1/8" or so of the cartridge is not supported by the chamber: Hence the slight buldge.

I reload for a couple older model 70 rifles. It is safe to go ahead and reload that brass. It will be necessary to full length resize those cases for use in your M1.

 

[evan price]

You should take a sharp piece of wire and feel down in the case for a ring that indicates brass stretch. IF found, junk the brass. Otherwise, a full-length resize will take care of the problem.

 

[fguffey]

(1956 would be control feed)

Depends on which model 70 Winchester, push feed or Mauser type control feed, the claw extractor on the control feed system pushes the case to one side with spring pressure, when fired the case can have wheat appears to be a problem, the 03 has less pressure, the M1917 has a little more and the Mauser has the most of the three, (control feed) a rifle that will allow the extractor to jump the rim when chambering a round has more room between the back of the extractor and receiver.

Brass and difference: Military brass, LC, EW, DM, etc has a thin head, average .200, commercial as in Remington has a case head thickness of .260, if there is a problem with case protrusion, real or perceived, commercial cases would be a better choice for peace of mind. No one list specification with head space to the .000 thousands with a case protrusion of .000? Every chamber I have measured with a cone faced barrel had a protrusion of .090 from the bottom of the extractor cut to the head of the case (I have been told case protrusion can be as much as .175 on an 03), every Mauser I checked for case head protrusion has had .110 + or - very few, it is so predictable when having the choice between 4 receivers, 4 bolts with one barrel the difference between any combination has been .002.

When sorting cases to purchase at the range I do not cull the cases that have have been fired in older Model 70 type rifles, at .09 cnets each.

F. Guffey

 

[fguffey]

have what appears--

sorry about that,

F. Guffey

 

[pyrolater]

I checked my extractor and it a little slidy thing on the bolt so I'm assuming it would be a pushfeed

I appreciated your input but I finally got out to shot a few rounds and this is what I found. All brass is federal commercial.

I marked 5 rounds with a sharpie where it says FC on the Base of the case and orientated the mark to the 12 o’clock position. If it moved when I closed the bolt I don’t know It sorta looked like the bulge developed in the same general direction. ( this is assuming the cases are drawn and stamped at the same time and any weakness would be on the same side or the chamber is over sized on one side ) Nothing conclusive,


Once shot brass diameter measured just up from the base of the case by the bulge is about 5 thousands over factory brass diameter

Head space on once fire brass was also about 5 thousands longer than factory brass.

The Bulge as best as I can tell is only about 1 to 2 thousands high. I did a little filing on my Sinclair run out gauge so the 30-06 brass would fit on it back wards. Any way I ran the gauge length wise over the case and my best guess is the so called bulge is only a .001 or .002 high.

I do not have the equipment to check the in side of the case.

I’m not sure what this is telling me other than I got a little bitty bulge on the side of the case. Next question is how will that little bulge affect the accuracy of my reloads??

Last but not least the LC brass shows no signs of any deformities.

 

[woods]

Does it look like this?



this bulge is happening where the brass goes from a solid case head to the open powder column



and just means that your chamber is a little larger than it could be and is very common.

The 30-06 shown in the first picture shoots just fine



No problem.

 

[fguffey]

http://en.wikipedia.org/wiki/Winchester_Model_70

"I checked my extractor and it a little slidy thing on the bolt so I'm assuming it would be a pushfeed"

http://www.chuckhawks.com/win_70.htm

The extractor on the pre 64 is not a small 'slidy' thing, 1956 would be a control feed system, when the bolt is closed the extractor pushes the case to the open side of the bolt, ammo when fired is violent, cases I have fired in most control feed feed systems leave a dent on the side of the case opposite the extractor, some do not leave a dent and are extracted looking like they were fired in a push feed system with a little 'slidy' extractor and the extractor in the face of the bolt have been know to leave impressions on the case head due to high pressure.

F. Guffey