30-06 cases tight in chamber

[Mk42gunner]

Sounds to me like this lot of old military brass is the problem, since you can use once fired brass from your rifle with the full length die with no issues.

I hate to say it, but I would set that lot of brass aside and not modify anything. The US hasn't used .30-06 as a common issue military round in decades. The last I am sure of is the Navy still using M-1's and maybe BAR's in the early seventies. .30 cal Browning's? Probably the 1960's.

Maybe it is age hardened and would be helped by annealing the brass first.

Robert

[Jim P.]

Sounds to me like this lot of old military brass is the problem, since you can use once fired brass from your rifle with the full length die with no issues.

I hate to say it, but I would set that lot of brass aside and not modify anything. The US hasn't used .30-06 as a common issue military round in decades. The last I am sure of is the Navy still using M-1's and maybe BAR's in the early seventies. .30 cal Browning's? Probably the 1960's.

Maybe it is age hardened and would be helped by annealing the brass first.

Robert

I have 4 different lots from different gun shows but they all do the same thing. They are pretty old though. The one lot says 1943 on it.

[high standard 40]

For those who contend that trimming a shell holder is a bad idea, Redding makes a "Competition shell holder set" that has 5 different tolerance shell holders in .002" (.002" through .010") increments that are designed to set the case shoulder back by those increments as needed. I agree that there are SAAMI specifications and that there are also allowable departures from those exact specs. All chambers are not alike and dies can also differ. There are allowable tolerances. If you have a chamber that is on the minus side of spec, and a die that is on the plus side, and a shell holder that is also on the plus side, I can see where an issue can result. I have this very issue with a Ruger American rifle in 308 Win which has a very tight chamber. I have a couple 1000 once fired brass for this rifle that I got from an LEO firing range. If I size this brass with a Redding full length die, making sure to set my die so that I have to cam over the press handle, the case will not chamber in my rifle. Even a Small Base Die didn't solve the issue. I have to use a .002" thinner shell holder if I want this brass to chamber. A previous post suggested resetting the headspace on the Axis rifle. This would probable be the best overall solution. I have considered doing the same with my Ruger American.

[swheeler]

1943 was corrosive primed, throw that brass away.

[Jim P.]

1943 was corrosive primed, throw that brass away.

I have some that I wet tumbled and loaded up and it looks good so I see no reason not to fire it.

[Wild Bill 7]

Try a 45 acp shell holder if you have one. RCBS dies use a number 3 shell holder for both 45 and 30-06 brass.

[Jim P.]

Try a 45 acp shell holder if you have one. RCBS dies use a number 3 shell holder for both 45 and 30-06 brass.

I dont have one. the only other caliper I have ever reloaded is 9mm and I do that on a lee progressive press.

[ulav8r]

OK, went back to the op and re-read most replies. After my first reply we are told gun accepts factory ammo so headspace is acceptable. Shell holder is .125, so it is nominally correct as to overall height but a shim between shell holder and case does produce acceptable ammo so dies are good. This indicates that the shell holder is off a little and everything else combined is near minimum.

I do not know the specification for top face of the shell holder to the base of the recess but it seems this shell holder is past max for this combination of components. A metal shim with a .215 hole in the center and glued/soldered into the shell holder would be a permanent solution that would maintain the usability of the dies. Removing .006 from the bottom of the die would not harm their use with other shell holders as long as the user is careful to set the dies for proper headspacing when installing in any press.

[M-Tecs]

This really isn't that difficult. The OP stated he is a machinist and as such he should have the capability to actually measure what is going on. Is it a chamber issue? Is it a die issue? Is it a brass issue? A technique issue? A combination of all of the above? Something else?

All could be easily resolved with actuals measurements. Without that blacking a tight case with a magic marker and chambering it would at least indicate were it is tight.

[Jim P.]

This really isn't that difficult. The OP stated he is a machinist and as such he should have the capability to actually measure what is going on. Is it a chamber issue? Is it a die issue? Is it a brass issue? A technique issue? A combination of all of the above? Something else?

All could be easily resolved with actuals measurements. Without that blacking a tight case with a magic marker and chambering it would at least indicate were it is tight.

I already blackened a case and it was only hitting hard on the shoulder. I dont have the proper tools to measure the head space but I definitely can machine a few thousandths off the die and size another case to try in the gun.

[M-Tecs]

You have an optical comparator at work?

[Jim P.]

You have an optical comparator at work?

we do not

[Three44s]

I would set that military brass aside and work with the commercial stuff that functions fine. If you must use that military brass I would wait until I could get a second sizer die and modify the least desirable of either your current FL die or the second one (yet to acquired).

If you cut your current sizer down for the military brass you have caused it to excessively size your commercial cases. I doubt that mil brass is worthy of a cut or second and cut die What with the corrosive primers that were used (other than match brass).

Three44s

[M-Tecs]

Proper adjustment of the dies is based on the shoulder setback for each individual chamber. Setting the die to the shellholder is the manufactures recommendation to size the brass to a minimum spec. to function in all firearms. Nothing more. The sizing die does not need to contact the shell holder. Same of the claimed slack and or frame stretch. The force of the sizing does that and provides the load.

[jim147]

yes I have and they will chamber fine but they will also chamber fine before I size them. I will say that the brass I was having problems with is military brass and it takes a lot of pressure to resize this brass. Much more than it does to resize the brass shot from my gun. the chambers on the military rifles must be a lot bigger or are just worn out.

That answers it. Your die and shell holder are fine. That is old hard brass that was fired in full auto/big chambers. It needs to be checked closely for separation and then if no signs maybe aneal and see what happens.

If you modify anything your good brass will get overworked and in my opinion less accurate.

[notenoughguns]

That answers it. Your die and shell holder are fine. That is old hard brass that was fired in full auto/big chambers. It needs to be checked closely for separation

If you modify anything your good brass will get overworked and in my opinion less accurate.

Jim147 hit the nail on the head !!
You need a small base sizing die to use that old military brass , more than likely base at the web is oversized and and is were the hangup is . If the die and shell holder work on commercial fired brass then your dies are fine ! old full auto military brass is the problem !

[uscra112]

He's already proven that the sized cases aren't too big at the base.

[M-Tecs]

I already blackened a case and it was only hitting hard on the shoulder. I dont have the proper tools to measure the head space but I definitely can machine a few thousandths off the die and size another case to try in the gun.

Per the OP the issue is not the base it is headspace only. The question is why only on the GI brass? The GI brass could have more spring back for a variety of reasons. GI brass tends to be harder and depending on what it was fired in possibly a longer chamber.

[uscra112]

I'm willing to consider that the hard brass hypothesis might have merit. Anneal a couple and see what happens.

[1hole]

I definitely can machine a few thousandths off the die and size another case to try in the gun.

Maybe. Most (all?) sizers are case hardened. Even with a carbide tool that's hard to cut. I've had good luck on sizers with grinders tho, once you're thru the case the interior is quite soft.