Three decades of brass; Measuring OAL on belted mag

[fiftycalforsquirrels]

I've got a couple questions which don't really relate to each other but figured I'd make 1 thread instead of 2.

1st question,
My girlfriends grandpa gave me about 5 boxes of brass that hes been collecting since back in the day. He mostly hunts so I don't think this brass is all one lot # and was probably bought over the years. One of the boxes has '95 written on it for when he bought it. And a couple other boxes look a little more vintage than the one marked '95. Another box and a baggy of brass, if I were to guess, look to be from somewhere between '95 and now. It's pretty much all federal, and once fired out of his rifle.

I myself have a box of federal that was purchased pretty recently. I'm wondering if I can just toss all this brass into the tumbler, full length size it, load it, and pay no attention to what year the brass might have produced?

2nd question,
I am looking into finding the max overall length for my rifle and am considering a hornady overall length gauge and am wondering if it would be worth it for a belted mag application. I'm assuming if I used hornadys tool with their shell, it would head space off the belt and give a different reading opposed to a shell head spacing off the shoulder. If I planned on fire forming brass and head spacing off the shoulder, would I be better off making a tool that gives me an overall length with the once fired brass and the shoulder bumped back?

 

[alberta tactical rifle]

"I myself have a box of federal that was purchased pretty recently. I'm wondering if I can just toss all this brass into the tumbler, full length size it, load it, and pay no attention to what year the brass might have produced? "

Yes you can but it is a dangerous practice. Case capacities could vary significantly. Checking the case capacities would be a wise idea.

There is a huge difference between OAL and headspace, 2 completely different dimensions and in different ends of the cartridge, so yes the Hornady OAL gage will be of benefit.

 

[fiftycalforsquirrels]

Yes you can but it is a dangerous practice. Case capacities could vary significantly. Checking the case capacities would be a wise idea.

Echo.

There is a huge difference between OAL and headspace, 2 completely different dimensions and in different ends of the cartridge, so yes the Hornady OAL gage will be of benefit.

The way I'm thinking of it is, a factory size un-fired belted mag will stop traveling forward in the chamber when the chamber comes in contact with the belt and will give one length reading. Though a fire formed belted mag case head spacing off the shoulder will stop traveling forward when it hits the shoulder and would give another, most likely longer reading because the case is stretched to the chamber and no longer uses the belt on the case to stop moving forward in the chamber.

Am I out to lunch here?

 

[alberta tactical rifle]

Echo.



The way I'm thinking of it is, a factory size un-fired belted mag will stop traveling forward in the chamber when the chamber comes in contact with the belt and will give one length reading. Though a belted mag fire formed case head spacing off the shoulder will stop traveling forward when it hits the shoulder and would give another, most likely longer reading because the case is stretched to the chamber and no longer uses the belt on the case to stop moving forward in the chamber.

Am I out to lunch here?

Not at all, your logic is sound. Full length sizing "should" set the shoulder back to very close to original dimension and then you would be able to establish proper OAL.
OAL is typically measured from the headstamped base of the casing to the bullet tip. For precision reloading the ogive is used for consistency as there will be a variance using the bullets tip. This is where the OAL gage comes into play as it allows you to seat at X distance from the lands to the ogive.

 

[c-fbmi]

I'm afraid that after more than 40 years of handloading I will have to disagree with atr..........If all your cases are Federal and you are not loading on the ragged edge at 5 gns over book max, you may consider them all one lot and carry on. I know guys that don't even brand sort their rifle brass let alone measure internal capacity or weight and have cases from as far back as 40 years and as recent as last week. It may not be conducive to the very best accuracy but within the bounds of loading manuals it will not ever approach dangerous. If you decide to "walk on the wild side" meaning above loading book max recommendations then you probably should start sorting and weighing cases and paying real close attention to pressure signs.

Your second question would depend a lot on which belted case you are speaking of........I treat my 300 and 375 H&H differently than I do my sharper shouldered belted mags. But in reality how you determine to size your cases has nothing what-so-ever to do with COAL. I'm old school and use a fired case and new bullet to determine my max COAL for that rifle and bullet, then I work from there. When setting my die I use the same bullet to set my die to the desired COAL I have decided on. By using a case fired in the rifle in question, you eliminate all headspace questions relevant to the COAL for that cartridge and bullet combination. Again, how you set your sizing die and size to minimum or maximum headspace still doesn't affect your COAL when it is done this way.

 

[kman300]

What c-fbmi said.

I use 300hh, 8mm rm, 340wby and 375hh brass from Remington, Winchester, federal, Norma/wby all of it resized to 300 wby for medium plinking loads. Couldn't care less if it's ancient, as the 300hh brass is or new range pick up. If you don't need warp speed I would never worry about it.