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Discussion Starter #1
I've got 2 Springfield Armory M1A's; a loaded and a SOCOM II. The issue I'm having is that it seems if brass is fired from either one of these rifles it's useless afterwards. The area up around the shoulder is oversized. I full length re-size using a Hornady .308 die and then bought a set of Dillon .308 dies to see if it would make a difference. With the Dillon it seems a little better, but not much.

In my check gage, the the base of the reloaded rounds are just barely above the top of the die and do not quite seat flush with the face. They will chamber in either rifle but there are extraction issues with the bolt remaining closed on the fired round. The rounds sized with the Hornady dies will not chamber in my Ruger 77 rifle, the rounds sized with the Dillon will chamber but it takes a lot of force to rotate the bolt closed. Running unfired .308 brass through either die set produces rounds that function perfectly in the M1A's as well as the Ruger.

I'm just wondering if I have oversized chambers in the M1A's. I'm also wondering if it's issues of firing .308 brass in 7.62 chambered rifles. Is there a die out there that could properly resize the brass? I'm hoping there's a fix because feeding these rifles is going to become expensize if I can't reload brass from them.

Thanks in advance.
 

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When you say "the area up around the shoulder" are you talking about the diameter of the body or the headspace dimension measured from the head to a datum line on the shoulder itself?

Without further info it seems to me that you are not bumping the shoulder back far enough. I.E. You need to turn your sizing die in further.

What method are you using to adjust your dies?

pg
USA2
 

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You will need a Small Base resizing die for your tight chambers....

and when I say "tight chamber" I am NOT referring to any headspace/chamber LENGTH issues

I am speaking of the cut of the actual chamber bore circumference/inside diameter or what have you

An RCBS full length die works fine for my GI barreled M14sa's

but those same rounds will NOT chamber in my brother's Savage Tactical bolt rifle..

I need to use a Small Base Die on the brass for his rifle

As for your unfired brass it is set to minimum-side of the proper spec

and running it through the full length die is like sticking a size 8 foot in a size 14 boot
 

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Dillon's 308 die is a small base die.
Try what polygunner said and turn your die a little until the sized case will fit in the case gage properly.
 

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Discussion Starter #5
Diameter at the neck is 0.340, at the base of the shoulder it's .4545 just a hair the .4540 that my loadbook calls for. I'm assuming that it is headspace is the issue since the the base of the case is protruding above my case gauge. With both sizing dies I've got them screwed down to the point where the bottom of the sizing die just barely clears the top of the shell holder.
 

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You need to screw in your sizing die further. Just touching is not enough.
My shell holder contacts the bottom of the die solidly, to the point where I feel resistance without brass in the die.

Screw in the die 1/8th to 1/4 of a turn and try again.

Get yourself a Head space comparator so you can track how much your sizing the brass.

Fire a few cartridges with the gas system turned off and measure the HS dimension and size your brass a few thousandths less than the fired brass.

Hope that made sense.

pg
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Dillon told me that you can continue to screw down the die (within reason) until the resized case fits properly into the gauge. I had a very similar problem until I did this. No problems with my reloads since then. This amounted to more pressure when the ram reaches top-dead-center but they said it was acceptable.

Eagle 1
 

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Look at the gap between shell holder and bottom of the die when a case is actually being sized.
Usually there is enough clearance to lower the die a little more.

Each full turn of the die (14tpi) is about 0.072 inch.

Jay Kosta
Endwell NY
 

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Check your case length. If the case is over 2.005, trim it back until it either seats in the case gauge or you find that this is not the problem, whichever comes first.
 

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I found I had a problem using a shell holder from one company with dies from a different company. There was a slight difference in the depth between manufacurers.

So I compared shell holders and used the one with the shallowest depth.

I also adjusted the die so it takes a little effort to raise the arm without brass, them make sure there is no daylight between the die ande shell holder when the arm is all the way up. I was using Military surplus brass and had the same problem with my SA M1A chamber.
 

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You can also take your shellholder and on a hard flat surface put a piece of emory cloth and run the shell holder over the emory a couple thousanths at a time try running a case up and see if it fits. If no go keep sanding until the case fits in the guage.
 

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Discussion Starter #13
Thank you everyone for your help, I did some checking on my die set up and I think I may have identified my problem(s).

First I now have set the sizing die set further downward. Previously I had it set so it was just short of making contact with the shell plate. I now have the Dillon sizing die screwed down so that it is making contact with the plate and there actually is a little pressure exerted on the plate.

Second, I backed off the body of my seating die and set the seating stem further downward to maintain seating depth. I believe what was happening was that the seating die was too low making contact with the shoulder of the case and slightly "crumpling" it, causing the shoulder of the case to buldge. Previously the shoulder was measuring at .4545 diameter, it's now at .4500.

I took pieces of once fired brass from one of my M1A's for use in re-setting the dies and checked it against my chamber gauge and by test chambering in my Ruger 77 after every step. Before adjusting the sizing die, the base of the case protruded just a hair above the chamber gauge and was extremely difficult to close the bolt on the Ruger. After adjusting the sizing die downward the base of the case is absolutely flush with the check guage and chambers easily in the rifle. After seating and before adjustment of the seating die, the test rounds chambered in the rifle but the bolt handle was difficult to rotate closed. After backing the body of the seating die off, the test rounds easily chamber and the bolt is easy to close.

Hopefully this has solved my issues. I'll be loading up a few rounds and grabbing one of my M1A's for the next trip to the range.
 

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When it comes to 308 Win and 7.62 I've found it best to NOT interchange the two. Mil spec brass tends to be thicker than 308 Win and I, and others I have known, have experienced pressure problems firing 7.62 Nato in rifles chambered for 308. When reloading fired or virgin brass I won't mix then either.
As far as sizing goes I use:
RCBS Small Base die for the M1A
Neck sizing for fired brass in my Ruger 77
Standard sizer and full length resize for my Savage 99
 

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I've experienced the same thing with Lake City/ military brass it does in fact have a thicker case wall than most commercial brass. This is something most reloading books I've seen, do not tell you. If using LC brass, drop your charge by .5 grains as a rule or you could run in to a over pressure issue. This may be a bit off topic, but I do not want someone who doesn't know this to find out the hard way.
 

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Too much taper crimp will cause the shoulder bulge for sure. I had to pull apart 400 rounds back when I first got started because of this problem. I could barely feel anything in the press handle when the crimp was being applied and the bulge was so slight I couldn't see it with the naked eye, but only one in 10 rounds would chamber. That was in 1981 and I haven't crimped a bottleneck round since then.

Another sizing trick that helps with M1A brass (and once-fired brass you get on the internet that has been fired in a machine gun) is to size the case, then rotate it 180 degrees in the shellholder, then run it into the sizer again.
 

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Another sizing trick that helps with M1A brass (and once-fired brass you get on the internet that has been fired in a machine gun) is to size the case, then rotate it 180 degrees in the shellholder, then run it into the sizer again.
I've done that one many times; it works well for me too.
 

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The case gauge is designed to check for proper diameters and the trim-to-length, it doesn't check headspace. If the cases weren't seating flat in the gauge then that means that your resizing die was not going down the length of the case enough, in other words, you need to turn the die down deeper in to the press. Most manufacturers recommend turning the die down until the bottom of the die just contacts the shell holder.

But, while turning the die down, the case diameters at the base and at the shoulder will become smaller. It will also shorten the headspace dimension of the case (it bumps the shoulder back). Overall the case will become smaller in every dimension except the overall length. Since all the diameters and the headspace will all be compressed, the brass will extrude toward the neck of the case. This will make the case's overall length (from base to case mouth) grow during the resizing.

The die that works the best for me is the Redding full length, type S bushing die. I reload for a standard, a loaded, and a SOCOM 16 and this die makes my brass work for all three rifles.

Sticky cases, in respect to sizing, are usually the result of the case being too large, either in length or diameter. There are several ways that this can happen. The case can be too large to begin with (not resized small enough) or the chamber could be too large and the case expanded upon firing.
 

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Redding makes a competition shellholder set size #2 part # 11602. Six shellholders in .002 increments. It lets the shell go further into the die without camming your ram over. These will solve your problem.


http://www.midwayusa.com/viewProduct/?productNumber=102174
Those are all "+" shell holders. I have that set for 308 and another for 223 sized case heads.

All of the shellholders allow you to size the cases longer than a standard shell holder, but not shorter.
 

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Those are all "+" shell holders. I have that set for 308 and another for 223 sized case heads.

All of the shellholders allow you to size the cases longer than a standard shell holder, but not shorter.
Really? The ones I have make the case shorter, just like their advertisement says
http://www.midwayusa.com/product/102174/redding-competition-shellholder-set-2-7-30-waters-30-30-winchester-32-winchester-special?productNumber=102174

Notes:
Packaged 5 piece set in .002" increments (+.002", +.004", +.008" & +.010")
Each shellholder is clearly marked to indicate the amount it will decrease case to chamber headspace.
Set allows you to adjust case to chamber headspace of your reloads with a simple shellholder change.
http://www.sinclairintl.com/.aspx/pid=39926/Product/REDDING-COMPETITION-SHELLHOLDER-SETS
The five shellholders are +.002", +.004", +.006", +.008", and +.010" thicker than normal shellholders
 
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