Brass age?

[dsnook]

Good morning folks,

So, it looks like I might be getting a new M77 for the stable. It will be a 7mm RM. I have a couple of sets of dies for this cartridge, and several hundred rounds of brass. My worry is how old my brass is. I got my 1st 7mm when I was 15...41 years ago! I doubt I have any brass left from then, but it could be as old as 30 years...perhaps somewhere in between.

Besides cleaning (which I have already done) and close inspection, is there any thing else I might consider?

TIA
D

 

[Dr. Vette]

Do you ever anneal your brass?

I would consider doing that, or using one of the relatively inexpensive services that does it for you. You might also consider running them through a Willis collet die before using them in the new rifle to be sure they'll fit.

This is the routine I go through if I ever purchase used brass so that I start out with some that is "as close to new" as I can make it.

Age should not otherwise affect it.

 

[JD338]

So long as there is no corrosion you should be good to go.
Of course, you could treat your new rifle to some nice Nosler brass.

JD338

 

[DrMike]

So long as there is no corrosion you should be good to go.
Of course, you could treat your new rifle to some nice Nosler brass.

JD338

As usual, JD338 is spot on. Dr. Vette has good advice if the brass has been previously fired, especially if it has been fired an unknown number of times.

 

[OldMan]

Anneal the brass, check for case separation with the long hooked wire method, and don't be surprised if the brass from the older rifle is to long on headspace or to short. To long, you can just push it back with full length die. To short and you will need to neck up first, then size to leave a false shoulder on brass for fire forming. I tried using old brass on another 7 mag and found it separated upon firing because the new chamber was shorter. Cured it by doing the false shoulder routine. Either the chamber dimensions have changes in later years or chambers for magnums can vary a bunch!

 

[Elkman]

dsnook, following the advice here, will keep you on the right track. I still have some good looking Herters brass!

 

[Wincheringen]

Anneal the brass, check for case separation with the long hooked wire method, and don't be surprised if the brass from the older rifle is to long on headspace or to short. To long, you can just push it back with full length die. To short and you will need to neck up first, then size to leave a false shoulder on brass for fire forming. I tried using old brass on another 7 mag and found it separated upon firing because the new chamber was shorter. Cured it by doing the false shoulder routine. Either the chamber dimensions have changes in later years or chambers for magnums can vary a bunch!

The various belted mags headspace on the belt, so yes chamber dimensions are quite varied.

 

[dsnook]

thanks guys, Most of this brass is from my old M70 that I had. I loaded so I head spaced on the shoulder instead of the belt. I found I had zero case separation that way. That M70 was a shooter! It started out life as a push feed Ranger, then I installed a B & C stock...bedded of course. My wife has been very patient with me and all my gun trading. But she occasionally reminds me how good my "magnum" shot when I get frustrated with a new gun.

D

 

[BretN]

The brass for my 30-06 is all Lake City match head stamped 62 or 63. I believe it was all once fired when my uncle gave it to me and I have reloaded it twice with no problems. On the other hand, I have some 243 brass that is only once fired and 10-14 years old and have had some spit necks on the first reloading.

Probably the right answer in both cases is to anneal them so that you don't have to worry about it. I've researched how to do it, but haven't taken the plunge yet. I can get brass cheap enough for all my guns that I don't need to get a ton of loadings out of it.

 

[Polaris]

Either way, annealing or not, you likely have inconsistent brass. I would acquire some new brass for your top loads.

This is fine for casual practice shooting or shorter hunting ranges.

I wouldn't mess with annealing it. I routinely reload WWII vintage brass in my M1 Garand. Got a large pile of it a few years ago from an old time match shooter who gave up the game. I'd just use it for casual shooting.

I think if the metallurgy was good to start with, age of fired brass makes little difference in serviceability.

 

[SJB358]

It's an interesting coversation. I really do all I can to conserve my brass to the utmost. Hence why I learned to anneal. I check for case head sep and what not, but honestly, unless I hammer a primer pocket loose, I've got a lot of life out of my brass. I'd bet some of my 338 and other magnums are upwards of 10 or better firings on them, but annealed and tumbled they look excellent. Big cost savings for me that way.

 

[truck driver]

I haven't lost but one in the 35AI since I started annealing after 5 loadings and that one wasn't split but had what looked like stress cracks in the neck. This brass has seen lots of use with me using the same 20 pieces over and over for load development.

 

[preacher]

I recently bought some once fired brass off Gunborker (7mm mag) in Federal and Winchester. Lord only knows how old they were....the Federals were too soft for anything like decent pressure and several of the Winchester "split while still in the ammo box"!!! Yep, got to the range, and several had slpit at the neck, some along the entire side of the case body! These were full cases, but hardly compressed. I jetted both brands and now have some new Winchester cases....but they are not really "made" by Winchester anymore, so who knows? time will tell. I don't anneal anything, but I do have one of those Willis collet dies. Nice die. If you are not sure....sell or trade off your old brass and buy new. Good luck to you Pard.

 

[truck driver]

With all the different answers about old brass or heavily used brass which ever the case may be I decided to check the 35 AI brass that I fired formed in my 35 AI. I had formed 25 new Nosler pieces and 25 new Remington pieces when I got the rifle back from JES last year and have only loaded the Nosler brass since the water capacity was greater than the Remington and wanted to keep everything the same when working up loads. Each piece of brass has been loaded at least 6 times but some have been loaded more because I also have tested some 225gr Sierras,225gr ABs and some 250gr BT with this same brass. So in reality I don't know for sure how many times it's been loaded. But let's just say a lot with both light and heavy loads up to 65Kpsi.

Today I decided to do some checking on the inside, outside diameter of the case neck. I also checked the thickness of the brass at the case mouth.
These cases have been used for all my testing and I have gone threw 150 200gr ABs looking for the right powder, charge and seating depth.
The cases have all been freshly annealed.
The case mouth inside diameter of 5 case sized in my Redding dies with expander in place is .353". The outside diameter of the case neck is .378" The thickness of the brass at the case mouth is .012". I also measured 5 new unfired 35 Whelen for neck thickness to see if there was any difference and there might have been .0005" between the used and new but I don't have the means to measure anything that small.
From what I can tell from my measurements there is very little change in the brass until metal fatigue shows up.