Trying to size 7.62x51

B

Bytesniffer

New member
I am pretty new to reloading.
Only been doing it for six months
So I can definitely be a dufos
At times.
I have reloaded full sized and neck sized 308 brass for my savage. No issues.
Some of the brass I bought new , some I resized after firing etc.

So, I buy 500 rounds of 7.62x51 (WMA 2015) clean it nice (tumbled)Brass and adjust my full length die
1/4 to 3/8 turn after hitting case holder
Lube up a case , size it, then put it in Wilson headspace gauge and to high.
Will guess I need a little more of a turn
Give it another 1/4 turn. Try again
Case is still to high. Slide a new razor blade over head space gauge and it hits.
Well after taking die apart and cleaning it,
And three full turns of sizing die. I wanted to crush neck. Nothing
Didn't crush it and still is up to max on headspace gauge.
Anyone know what's going on. ?
Tried it with 5 different cases.
 
It doesn't matter what the Wilson headspace gauge says as long as the brass fits in your chamber. So test it out in your chamber.

But, excessive brass spring back could be a sign you need to anneal your WMA 2015 headstamp brass. So a anneal five cases that didn't size right before, and see if that fixes the problem.

Jimro
 
If you've never done annealing before, the slow but simple way is to hold the casehead between thumb and index finger, rolling the thing back while you hold the neck and shoulder in a candle flame. When the case head starts to get too warm to hold onto, wipe the soot off against a damp towel or drop it into water and wipe the soot off later. Either way, you have a case you can try resizing again.

Turning the die down further and further is just stressing your press needlessly. Once you reach the point there is no crack of light between the die and the shell holder with the press ram fully extended, the die isn't letting the case in any further. That would require grinding the die mouth back shorter. Or, there is one other thing you can do:

You can remove the decapping pin from your die and try board member F. Guffey's trick of slipping an automotive feeler gauge under the case head in the shell holder so it elevates the case by that amount. If you put in, say, a 0.005" feeler gauge, that's how much shorter the die will make the case on the next pass.
 
Great ideas
I'll try the feeler gauge first
Then annealing.
Hope I don't have to anneal 500 cases.
Also, the cases I have been working with
Resizing to death I'm going to throw out
But the headspace gauge says
Up to max but they chamber fine in my 308
Go figure.
 
The headspace gauge is designed to tell you if the cartridge passes for loading in a chamber at the small end of the tolerance range. Most guns don't have a chamber with minimum headspace, but rather are between minimum and maximum, so most guns are fine with a slightly longer case than the gauge passes. If you want to maximize the life of your cases, you want to measure the length of the case as fired in your chamber, and only run it into the die as far as necessary to come out a thousandth shorter for target shooting and two or three thousandths shorter for reliable fast feeding from a magazine.

You can buy an adapter for your caliper with inserts for comparing case. You can, however, just buy a fat spacer from your hardware store whose hole lands over about the middle of the case shoulder. Set it on the case shoulder to use it. It's a little slow going, juggling the case, caliper, and spacer, but that's OK just to get a die set up or to sample a few cases. Basically, first measure a fired case and zero the caliper on it. Then you can check your resized cases to see if they are shortened adequately for your chamber.

Below is an example of measuring a .308 Winchester case this way. The caliper is a 12", so it's a little bigger looking than the usual 6", but both work.

poormancomparator_zps061e19f7.jpg



Below is an illustration showing what happens to brass during resizing.

Shoulder%20Setback%20and%20Growth%20II_zpsvgwe5rip.jpg
 
You check the case lengths?
It is highly unlikely annealing is required. Annealing is only done when cases get work hardened after repeated sizing and firing. It is not a part of the regular reloading process.
"...they chamber fine in my 308..." Like Jimro says, that is what matters. That Wilson thing(it is not a headspace gauge. Cartridges do not have headspace.) is only making things complicated for you.
 
Let me restate
The 7.62 brass that I resized several times
Will chamber in my 308, even though they
Are flush with top of headspace gauge.
7.62 brass that I put through the full length die with normal die setup
Are slightly above gauge.
Gauge with no shell in it , reads 2.015
With shell 2.025.
Can not chamber in ,308.

All the 7.62 I fired in my 7.62 rifle
Fit perfect in gauge, as does all 308
Ammo.
I don't have my 7.62 rifle here to check
Because I had to send the piece of junk back for repair. I'm an idiot for not buying a Remington or ruger like I was considering
But that's another story.
Tried annealing, tried putting .006 gauge under case holder. No difference.
Is this Lee full length sizer
The problem ?
Although a resized and resized the brass I was experimenting with all day , will chamber in ,308 chucked it all. To over worked.
I thought 7.62 was same dimensions as 308 except for thickness of case.
Don't understand.
Need to buy rcbs die
 
WMA -- Winchesters newer ammo plant
WMA 15 would have been fired in a machine gun
machine guns have an oversized chamber for
reliable feeding, and then some guns have a lot
of wear in the chamber resulting in a case that
is extremely difficult to size correctly, shoulder
way to long and or diameter of case is too big around

Your problems sound typical of others trying to size machine gun brass
some say a small base die does the trick, others sized what they could and trashed the ones that would not size
If it was me I would keep trying
Next time spend the extra and get the cases marked LR ( long Range )
they would have been fired in a rifle, and are much easier to work with
 
Firewrench044.
Think your right on
The brass was fired through a machine gun
I think I'm going to buy another full length sizing die, just for the hell of it.
Narrow base.
I'm going to wait until I get my 7.62 back
So I can chamber the resized brass in that chamber vs the 308.
 
Put a piece of 220 wet or dri sandpaper on a flat surface and using a figure 8 motion, sand a few thou off the top of your shellholder.

This will allow your case to go a little farther into your die. I use my surface grinder, but the sandpaper will work, just slow.

Over the years, I have had to modify a few shell holders this way. Solved the problem.

If you are shooting semi auto, you need .002-.003 of head clearance, try your sized cases in your rifle to be sure the bolt closes easily.
 
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When you use these cases be prepared for a
case separation (head of the case tares off )
leaving most of the case in the chamber
I would not hurt to get a broken case extractor
they are not expensive

Sounds like these cases have been stretched pretty good
with cases like that, that's how they will probably fail
 
I appreciate everyone's help / suggestions
Today.
All the reloading I have done so far has been a real pleasure, until today.

All the brass I was working with today
Is in the garbage. Overworked to death.
All the 308 brass I previously loaded fits in the gauge correctly.
All the 7.62x51 brass I fired in my rifle chambered for 7.62, fits perfectly in the gauge.
All the 7.62 factory ammo I have
Which has not been fired, fits
in the gauge perfect..
Looks like I bought $65 worth
Of NATO 7.62 brass that I just can't
Size.
Maybe , because it was fired in some sloppy
Machine gun as stated above ?
Or maybe my die just can't handle this out of spec
Brass ?
Now, I have to buy another die to find out if
Its my die or definitely the brass.
This has been a very frustrating day.
 
No way that its your die. Its the brass no questions about it. If you want to use the brass get yourself a .308 small base sizing die. That will work but as mentioned I'd watch that brass for case head seperation.
 
Anyone know what's going on. ?
Tried it with 5 different cases.
Click to expand...

If you are using a Lee die, then that could be the problem.

They sometimes ream the die too deep and it will not properly size the case.

7.65 Argentine FL die is the same.

The 7.5x54 FL die is too small (0.006" to 0.008") and way overworks the brass.

Get another brand FL die and you should be good to go.

As far as I know, there are a few other caliber of Lee FL dies in the same category.

If you are not using Lee dies, then as UncleNick suggested use Mr. Guffey's tried and proven feeler gauge method.
 
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I found a few useful tips for sizing 7.62x51. Pretty much all LC is fired in machine guns, as those are the only military firearms currently in service in 7.62x51. It is only the initial sizing that is difficult.

1. I use Lucas White Lithium grease as case lube, from Home Depot. Works incredibly well. I clean the cases before and after.
2. I take the expander assembly out of the die for the first pass at sizing. And then size again, this time in a small base die, with the expander.
3. Trimming is necessary as I get a wide range of sized lengths.
 
Also, some folks run their 7.62 MG cases through a .30-06 die before going to the .308 die, pre-sizes so to speak. Of course, not all of us happen to have a .30-06 die laying around, but they say it really helps with MG cases.
 
Bytesniffer,

I buy a lot of once fired 7.62x51 brass, and the first step in processing is to anneal using a propane plumbers torch. It doesn't take much time at all, and if you don't even need to drop them in water, just a steel bucket. You don't have to heat the neck until it's red, just until you get a little color change just below the shoulder. You should be able to do all 500 in about two hours at a reasonable pace.

Military surplus brass is good stuff, it just takes a little more love on the first prep.

BTW, love your handle, makes me think you use wireshark a lot :)

Jimro
 
"And three full turns of sizing die. I wanted to crush neck. Nothing "

How do you manage to crank the sizing die down THREE FULL TURNS after an initial "1/4-3/8 after contact"?
A: I'm pretty sure that would break MY press.
B: If your press has that much flex, you need a different press.
C: If the case holder is contacting the die at "break over" while sizing a case, lowering the sizing die more won't help.
 
Let just say again thanks for all the info from everyone.

I approached this issue again from a fresh perspective.
I used a new piece of 7.62 brass, never sized etc.
Measured 2.026
Tried to chamber not even close.
Trimmed to 2.001
Tried to chamber no go.
Put brass in Wilson gauge and measured it
2.0225

Adjusted die 1/4 turn after hitting shell holder and slightly more for slack.

Sized brass
Measured brass now 2.0055
Die definitely sized it. Length increased.

Chambers fine, smooth in
Rifle.
Brass still slightly above Wilson gauge.
Measured brass in gauge
Reads 2.019 now.
Put .006 feeler gauge
Between shell holder and brass
Resized.
Put back into Wilson
Gauge and measured 2.017
Two thousands diff.
Brass is still not below
Max on gauge.
I can just feel the case when rubbing
Finger over case in Wilson gauge

I still don't know why this brass
Doesn't drop half way between
The high and low marks, like the
308 brass does ?
I think I will be able to reload this
Brass several times without
Any problems ?
 
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