Resizing Dies too Long or Am I Doing Something Wrong?

[Kevin Rohrer]

I just started using the Hornady headspace gauge that attaches to a vernier caliper in order to get minimally FL resized cases for my M1A in .308. I have determined that the proper resized case measurement from the base to the datum point is 3.635". Unfortunately, in order get that measurement after resizing, I need to adjust the die down .016" (as measured with a finger gauge) more than there is room, as the die bottoms out against the shellholder .016" short of where it needs to be.

Has anyone else had this problem? I am guessing the FL die needs to be shortened a tad, unless I am doing something wrong. I have tried this with both Redding and Hornady FL dies and encountered the same problem.

I'll add that I have also encountered a problem seating .110gr. VMax bullets in a Redding seating die as the seating stem isn't long enough. Arghh. :killingpc

[bhn22]

Redding offers a competition shellholder set that may help you, depending on how thick the top of your current shellholder is.


http://www.redding-reloading.com/index.php?option=com_content&view=article&id=35:competition-shellholder-sets

[noylj]

I have no idea what the problem is. Your description confuses me.
If you full-length resize a case, it won't chamber?
Most complaints are that the sizing die is pushing the shoulder back and increasing head space. Often, you need a full length resized case to have a semi-auto chamber easily.
I have never had a full length sized case not chamber easily.
Bullet seating also has never been a problem.
Of course, I don't have any "case gages' other than my gun's barrel.
you can cut a slit in the case so the bullet is a slip fit and chamber it lighly in you gun and extract it and see what the MAX COL is with that bullet.
You can take a couple of cases that have been fired in your rifle and have a custom die or two made.

[Willbird]

Kevin how did you arrive at the resized case measurement ? Once fired cases cannot be any longer than the actual headpsace of the rifle (with repeat firings they can get a LITTLE longer, but not .016).

I DO know from learning the hard way that if you bump the shoulder too far with an M1a you will soon be looking for a broken case extractor.

For a reference check you can measure an unfired factory round and see if the resized case measurement you think is correct is within reason. For bolt actions I like to bump the shoulder .002. There was a thread here somewhere a couple years ago about shoulder bump for different action types.

[Kevin Rohrer]

I am not having a problem seating cartridges. I am using the headspace gauge w/ casings fired in the rifle to determine the minimum amount of resizing needed to work reliably.

The problem is that the die appears to be too long to FL resize the case so that it is .002 <the fired dimension, and I can't screw the die down enough to bump back the shoulder to get that measurement of 3.635", which is .002 <the fired dimension. I was hoping someone here used the Hornady gauge and can offer advise.

[Willbird]

OK then I am not understanding where you got the .016" number from ?

It is not uncommon for the die to be long enough that you cannot bump the shoulder. It is a built in safety ninny factor to prevent what I referred to when we were reloading for an M14 years ago (an M14 not an m1a). Anyway the redding comp shell holders go from -.002 to -.010 in .002 increments to do exactly what you are trying to do.

Shoulder bump will be different with different brands of brass, and will change if you anneal necks.

If you have a buddy who has access to a surface grinder you can have him grind .002 at a time from a shellholder til you get your bump you want.

Again I would recommended you do a reality check to some unfired factory ammo (or a forster "go" headspace gauge if you have one) and make sure your numbers make sense....the .016" reference alarms me.

[Swede44mag]

Do you have any factory ammo to check the dimensions against?
I had a problem with a Remington 30-06 years ago.
It would not fire my reloaded ammo consistently but would fire factory ammo.
I bought a Wilson head space guage to check for head space and case length.
I found I was bumping the shoulder to far the Hornady die was to short.

I have had one die in .243 that was to long don't remember the brand.
I took it over to the belt sander and shortened it a little at a time untill it would bump the shoulder far enough to fit in my Thompson Center Rifle. It may have been that the TCR had to short a chamber they have had some QC issues in the past.

[Larry Gibson]

Kevin

Using the "D" gauge, 3.635" sounds about right for a minimally sized case to fit in standard M1A. I'm assuming that a case sized to that does chamber and extract freely? Your cases are right about max with that measurement BTW. Most USmanufactured commercial, ball and Match ammuntion runs 3.627 - 3.629" with my gauge.

Concerning your sizing of the cases; does the shell holder (is it the correct shell holder?) bump up solidly against the base of the die when sizing?

The press lever should stop solidly and not cam over.

Larry Gibson

[Kevin Rohrer]

I made comparison measurements:

1. Factory, unfired milsurp, Cavim on headspace: 3.623"
2. Casing fired thru my M1a: 3.633" and 3.632" (4-casings; two of each measurement).
3. Casing resized with the die screwed down till it touches the shell holder, using both CH and RCBS shell holders: same as #2 (i.e. no shoulder bump occurred).
4. Casing resized using a Hollywood shell holder that looks to be thinner (am using a Hollywood Senior): 3.621".

So this apparently means that the first two shell holders were too thick and I need to stick with the Hollywood shell holder, or have my die shortened a tiny amount.

Am assuming that I need to bump the shoulder back at least .002 to get reliable feeding in my autoloader.

Larry: Yes, to your questions and I appreciate your reply.
Will: Thanks to you and the others. The problem appears to be a function of the long die and a too thick shellholder. I will take a look at the Redding shell holders (pulling out their catalog as I write this)...Hmmm, it says that the industry standard for shell holder thickness is .125" and their special shell holders ADD to this measurement.

I'll call Hornady and Redding tomorrow. But I still appreciate all the help.

[1hole]

The proper question isn't what your gage reads but how well the sized cases fit your chamber. For that, just use fired and sized case shoulder comparisions. The specific dimensions/numbers you're concerned about are irrelivant for useful reloading needs.

You are correct that the oft suggested Redding "comp" shell holder sets are thicker than normal so they limit, not expand, our ability to FL size.

[Kevin Rohrer]

Correct. I am using casings fired in the rifle for measurement, then subtracting .002 from the gauge measurement to arrive at a headsapace size that should chamber easily. I am having problems sizing other brass to that measurement due to the die being too long. What I am finding, though is that some of my presses have some flex to them when FL resizing and I can take advantage of that flexing to screw the die down farther than normal to reach the desired measurement.

I never stop learning.

[Firebricker]

Kevin, You can take a couple thousandths off your shell holder instead of the die. I bought a set of used dies in .243 one time with two shell holders and loaded a few rounds for a friend. A couple of them mis fired with light firing pin marks. Turns out on of the shell holders had been sanded down probably for a tight chambered varmint rifle. FB

[Larry Gibson]

Kevin

Sometimes dies out of spec do slip out the door so I'd call Hornady at this stage also if the FL sized cases are not chambering in your M1A. BTW; if you get another FL die I suggest getting the RCBS X-die (regular base as the small base is not needed with your M1A) as you will get much longer case life (upwards of 20 firings per case) and will not have to trim.

Larry Gibson

[1hole]

"Kevin, You can take a couple thousandths off your shell holder instead of the die."

If the 'problem' is the die, why fix the shell holder?

[ReloaderFred]

The reason you either grind or mill a few thousandths off the shell holder is because they're cheap. They're also easier to mill or grind than dies are.

If you measure the depth of several shell holders of the same caliber, from the same manufacturer, you'll find variations in thickness, but all are within the parameters for the caliber. That combined with a sizing die that is at the maximum of the parameters set for them, results in "tolerance stack" that produces poor results.

I've had to do this with shell holders for 357 Sig, as all the shell holders I have (6 in this caliber) wouldn't allow the case to go into either my RCBS, Redding or Dillon Carbide sizing dies enough to set the shoulder back so the rounds would chamber in either of my pistols in that caliber.

Used shell holders can be picked up at gunshows for around $2.00, so if you mess one up, it's no big deal. It also doesn't take a lathe to take a couple of thousandths off the top of the holder, like it does a sizing die. It's simple economics and ease of actually doing it.

Hope this helps.

Fred

[GLShooter]

The reason you either grind or mill a few thousandths off the shell holder is because they're cheap. They're also easier to mill or grind than dies are.

Hope this helps.

Fred

I had a set of Hornady 308 dies that would not move the shoulder back like the OP said. I did the shell holder thinning trick so I could get them going. Later when I had time I returned it to Hornady and they faced off the die for me for free.

Greg

[MtGun44]

Will a resized case chamber? If so there is no problem. This sounds like some sort of
measurement error.

Bill

[1hole]

"The reason you either grind or mill a few thousandths off the shell holder is because they're cheap. They're also easier to mill or grind than dies are."

Both sizer dies and shell holders are usually case hardened. I've never found one to be easier to grind than the other and it takes carbide cutters to machine either.


"If you measure the depth of several shell holders of the same caliber, from the same manufacturer, you'll find variations in thickness, but all are within the parameters for the caliber. That combined with a sizing die that is at the maximum of the parameters set for them, results in "tolerance stack" that produces poor results."

All true but the die & shell holder tolerance range is designed to prevent tolerance stacking from preventing sufficent sizing. But at least one is out of tolerance and it's more likely to be the die than the shell holder.

My point is that shell holders get swapped around a lot but the die is the die. Grind or sand or lathe cut a few thou, 5-6 maybe, off the bottom of the die and it will size the cases as needed. Even if he takes a off few thou too much it's still quite easy to adjust a die for the desired amount of shoulder set back.

[hiram]

Borrow a 308 die from someone and try it. Maybe you need a small base die.

[ReloaderFred]

Ah, that's the beauty of being the boss in your own shop. You get to solve a problem any way you want that works for you. What may be best for you, may not be best for me, but both methods still solve the problem.

For taking a few thousandths off a shellholder, I just use my drillpress, with a grinding wheel mounted on an arbor and use the drillpress vice as a milling table. It only takes about a minute to do and the surface comes out flat and solves the problem.

Hope this helps.

Fred

[GLShooter]

Borrow a 308 die from someone and try it. Maybe you need a small base die.

A small based die won't make a difference in shoulder location other than that it would be a different die with dimensions that were different than the original. IMHO

Greg

[7of7]

I'd just chuck it up in my lathe, and take about .02 off of it, and call it good. That way, there is more adjustment, and if needed, he can go way down there... But, having a die that does prevent you from going to far is well worth it.. I just size them so they will fit.
I had the same kind of issue with my weatherby, the ammo used in my other rifle, wouldn't chamber, so, I had to resize the brass.. all the stuff that I had resized already needed to be done as well.
I wasn't to happy.. but, now it is all good. I carry a broken case extractor with each rifle.. just in case..

[frank_1947]

I don't know where your getting 3.6 or whatever you said with a hornady headspace gage headspace for a .308 is 1.630 min and max 1.640 according to Saami specs

[Lloyd Smale]

watch shaving the shell holder. I have a new 7mag that needed the same and shaved two shell holders broke them both and stuck cases in the die both times. Ground down the die and it worked fine. Ended up just buying a small base die to size them. The small base die not only takes the bottom of the case down a bit more but will allow you to push the shoulder back a bit too. I was shooting once fired brass from a gun that obviously had a bigger chamber then my remington.

[Kevin Rohrer]

I don't know where your getting 3.6 or whatever you said with a hornady headspace gage headspace for a .308 is 1.630 min and max 1.640 according to Saami specs

That's the raw measurement I get including the length of the case gauge. Subtracting the length of the gauge (2.003) from the raw number gives me a headspace of 1.630" (3.633-2.003=1.630"). I think I need to bump the shoulder back a bit more to 1.627".

I've been looking for headspace sizes but haven't found them in any of my reloading manuals.

[Larry Gibson]

Kevin

Your measurements are correct with that gauge. A couple things; fired cases from an M1A using .308W or milsurp spec ammo will most often have a longer cartridge headspace than that of the chamber. Let me suggest this to get a chamber headspace measurement with your tool and dies. If you know how and can remove the extractor, ejector, firing pins and associated small parts from the bolt and reassemble the rifle.

Back the die out of the press 1 turn from the shell holder.

Size a case that has been fired in your rifle.

Trim the case mouth back to a case aol of 2.0" (don't want the case mouth the give a false fit).

Insert the case into the chamber and ease the bolt forward. Do not let it slam as that will partially size the case. The bolt should not close (the case should not yet be fully sized). If the extractor and ejector are still in the bolt push on the oprod until the extractor snaps over the rim, it still should not be fully closed. Gently extract the case.

Wipe off and relube the case. Turn the die in 1/16 of a turn. Size the case, wipe lube off and repeat trying to chamber.

Continue with 1/16 die adjustments until the bolt just closes and the oprod goes fully forward.
When that happens the case is sized to the headspace of the chamber of your rifle. This is the maximum case headspace for your chamber. Measure that case headspace with your tool and write it down. Then adjust the die to size your cases .001 - .002" shorter case headspace for reliable functioning.

Larry Gibson

[Char-Gar]

I have two comments, but bear in mind I have never loaded for an M1A. But I think is is a basic Garand action that has been modified for the shorter round and a detachable magazine.

1. Some times we can get lost in the minutia of reloading and forget the basics.
2. In a Garand, we don't want to do partial resizing on cases. We FL size and take the reduction in case life that comes with that. We don't want to run the risk of a too long round and a slam fire in a dirty chamber. We want a little wiggle room with the loaded round.

These things are no bench rest rifles and properly set up/tuned will win the match without bench rest reloading.

[Kevin Rohrer]

Larry,

This is the information I need and I appreciate it. I follow what you are saying, but could you explain why a cartridge fired in my rifle would end up w/ a longer headspace than the chamber it was fired in?

[ReloaderFred]

Kevin,

The theory is that the action of the M1A/M14 is so fast that there is still pressure inside the case and barrel when the bolt unlocks and starts to the rear. This causes the case to stretch while it's being extracted.

I tested this theory on my Standard M1A by closing the gas valve and firing the rifle as a bolt action, manually working the bolt to eliminate any possibility of case stretching beyond the chamber length. In "my" rifle, there was no difference in headspace measurment of the fired brass between firing the same load manually or in semi-auto mode. I can't test my National Match M1A in the same manner, since they modify the gas valve so it can't be closed on those rifles.

I measured the brass from both of my rifles with my RCBS Precision Mic dies to come up with a sizing die setting. The NM rifle does have a slightly shorter chamber than the Standard rifle does, but by only about .001".

You might close the gas valve on your rifle, if it's not a match rifle, and see what your results are.

Hope this helps.

Fred

[Larry Gibson]

Kevin

ReloaderFred gives you the theory and what he found. I did the same test years ago using several M14s (I had 20 of them in very nice condition in my arms vault) using reloads, M118, M80 and Special Ball ammuntition. Wasn't a for sure thing with any specific ammo in all the rifles. Seemed it just depended on the particular rifle and particular ammunition. On those that did increase case headspace on extraction (about 55 - 60% of the time if I recall correctly) the increase was .001 - .003". Having to bump that shoulder back that additional amount is one reason some rifles only got 3 - 4 firings per case and some got more with the same loads (mostly 41.5 gr 4895 under the 168 MK back then). Even using the same loads from the same dies there was a difference in case headspace of the fired cases and the number of reloads per case individual match grade M14s with match chambers cut with the same reamer. That's my "theory" on that anyways. It does happen but not always. The X - die solved the problem any ways.

Larry Gibson

[Kevin Rohrer]

I don't have a Match rifle. How do I close the gas valve?

[ReloaderFred]

Up at the base of the gas cylinder there is a screw just under the barrel. If you use a dime and push in on the screw, you can turn it 90*. That will close off the gas port. This was used for rifle grenade launching from the M14.

After you've fired about 5 rounds to get an average, don't forget to open the valve again.

Hope this helps.

Fred