Why do you need Depriming pin?

[gifbohane]

So- Suppose that this is your process. First you only deprime a rifle case, like 556, in one step and then later in your processes (after say cleaning the primer pocket) you size it, you need to leave the depriming pin in to size mouth of the case on withdrawal from the die

Any further reason?

What would be result if you entirely withdrew the depriming pin and its rod assembly from the die and then you resized the case?

 

[Bazoo]

The sizing die sizes a bit smaller than needed to allow for brass of slightly varying thickness. The expander button expands the case mouth to just below bullet diameter for uniform neck tension.

You can size cases without the expander button or decapping stem. I omit the expander button when loading 30-30, but I use a lyman M die after sizing. This gives me not only expanded case necks, but a step to help get flat based bullets started.

 

[AJC1]

Nothing except smaller case mouths. This is exactly what I do, then use a mandrel to set neck size.

 

[Howa 9700]

Not sure if I've ever duplicated that process, but I have resized pulled down brass. Both Lake City and my own. For that process, one needs a sizing die that uses a removable depriming pin. Lee dies, with integral pin and sizing mandrel won't work for that.

 

[gwpercle]

When a case is fully sized , due to varying thickness of the neck wall ... the inside diameter of the neck may vary . To insure the inside diameter of the neck is the perfect size and consistent ...
the neck is sized a tiny bit smaller on the upstroke but on the downstroke the neck is pulled over the Neck Expanding Button giving the inside diameter it's final and correct form/size .

The decapping pin has nothing to do with neck inside diameter size .
If a case has been deprimed ... the decapping pin can be removed ,,, BUT
the rod and neck expander ball should not be removed .

If you remove the rod and neck expander ball from the die ... your resized cases will have Wonky neck sizes ... some too tight and some too loose ... aka... " inconsistent neck tension " ...
You don't want inconsistant neck tension ... that is not good .
Gary

 

[AJC1]

When a case is fully sized , due to varying thickness of the neck wall ... the inside diameter of the neck may vary . To insure the inside diameter of the neck is the perfect size and consistent ...
the neck is sized a tiny bit smaller on the upstroke but on the downstroke the neck is pulled over the Neck Expanding Button giving the inside diameter it's final and correct form/size .

The decapping pin has nothing to do with neck inside diameter size .
If a case has been deprimed ... the decapping pin can be removed ,,, BUT
the rod and neck expander ball should not be removed .

If you remove the rod and neck expander ball from the die ... your resized cases will have Wonky neck sizes ... some too tight and some too loose ... aka... " inconsistent neck tension " ...
You don't want inconsistant neck tension ... that is not good .
Gary

I guarantee none will be to loose.

 

[Demi-human]

I guarantee none will be to loose.

Some may not even accept a bullet and crumple under the pressure. It really needs to be the right size.

What would be result if you entirely withdrew the depriming pin and its rod assembly from the die and then you resized the case?

It would be sized perfectly and be ready for loading.
Provided they were neck turned and full length sized with a bushing style die.

I de-prime and clean before anything else as well.
I grind down, or replace with a smaller button, the expanding ball in my sizing die so I can use an expanding mandrel instead.
Using a mandrel keeps the neck and shoulder more concentric. Leaving the extra de-priming pin in the sizing die ensures there is nothing occluding the flash hole, or I didn’t miss a primer, on the second run through. And because there is no work done on its removal from the case, there isn’t a real reason to take it out of the die.

Of course, with pre-processing, there isn’t a real reason to leave it in.

Shooters choice really, in this instance.

Just as long as every step is done to every case the same way.
I’ve been trying(/failing?) to teach my kids that it’s a lot harder to do things the exact same way, every single time, every single day, than they think it is.

 

[Blue68f100]

Most of my dies have had the pin removed from the sizing dies. I deprime prior to wet cleaning. Unless the pin is needed to keep from damaging the stem that holds it if the collar/expander is over tightened.

 

[Kaldor]

I removed all ball expanders and decapping pins from all my dies, pistol and rifle, probably 5-6 years ago.

When I decap, I use a purpose built decapping die as Ive found them to be much more durable. Take your pick, Lee, Mighty Armory, FW Arms, etc. Those are just the ones Ive used. I wet tumble, so decap first, but one could dry tumble then decap if thats your deal.
When I size rifle, Im just bumping the shoulders with my dies, and setting an initial ID for my case mouth. I do anneal before I start sizing. I also wet tumble after this as the mandrel will remove any case mouth dings prior to loading. I am also slowly moving to progressive sizing and trimming for my blaster ammo.
When I size the necks, I use a Sinclair mandrel or Lyman M-die. I find that I get alot less brass stretching doing this than dragging an expander button thru the neck and accuracy for me is improved.

Bear in mind, the majority of my ammo gets loaded on a progressive. Rifle has to be double run anyway, so when I load rifle on the progressive, I just drop my M-die in station one to set neck tension right before I load the bullet. SSTL media does a good enough job deburring, and a Lee FCD with a kiss removes the light M-die flare.
The ammo I dont load on the progressive is more work intensive, as I decapp, size, tumble, mandrel, trim on Giraud, then load, but I find it to be very accurate for me.

 

[Charlie98]

I omit the expander button when loading 30-30, but I use a lyman M die after sizing.

I tried that with my .348WCF brass... dumb move. The next step was trimming... without the expander ball opening up the necks, I couldn't get the trimmer pilot into the case mouth. If I didn't need to trim, that would have worked, but I don't measure a case for length until it's resized... and then it's too late.

 

[EricBu]

I deprime my brass, then clean. I leave the pin in place just because I like to make sure the primer flash hole is clear and didn't end up with something plugging it.

 

[Bazoo]

I tried that with my .348WCF brass... dumb move. The next step was trimming... without the expander ball opening up the necks, I couldn't get the trimmer pilot into the case mouth. If I didn't need to trim, that would have worked, but I don't measure a case for length until it's resized... and then it's too late.

You are absolutely correct. I modified a spare trimmer pilot to be slightly smaller in diameter to remedy the problem. I don’t remember what diameters it was vs what I made it. But I chucked it in my drill and sanded it down then polished progressively finer.

I’ve heard people will trim after M die expanding, but I never tried that. I figured it better to trim after sizing.

 

[AJC1]

I tried that with my .348WCF brass... dumb move. The next step was trimming... without the expander ball opening up the necks, I couldn't get the trimmer pilot into the case mouth. If I didn't need to trim, that would have worked, but I don't measure a case for length until it's resized... and then it's too late.

I use the same procedure on my pistol brass to trim after mandrel for the same reason.

 

[Walkalong]

I guarantee none will be to loose.

lol, true, but the inconsistent neck tension/seating is a serious issue for anything other than blasting ammo.

 

[Walkalong]

It doesn't hurt anything to leave the pin in, and it might knock corn cob out of the flash ole if left in, assuming you tumbled the deprimed cases in it.

I don't take them out, including the calibers I use neck bushings and expanders instead of a regular die/expander ball.

 

[CoalCrackerAl]

I de-cap with a universal de-cap die. I take the pins out of the sizing dies. I think it helps the sizing die breathe some.I haven't had any lube dent's either.

 

[jmorris]

What would be result if you entirely withdrew the depriming pin and its rod assembly from the die and then you resized the case?

It would be like sizing any straight walled case, you just need another step with an expander. Like a powder through expander.

They generally require a large caliber to prevent powder bridging problems.

 

[JFrank]

When I removed the expander ball from my old Forester die I remember about .007 reduction at the case neck, far too much for my liking, on the other hand with the ball intact I recall a pie dough effect thinning out the necks again too much for my liking so I just went with Wilson FL bushing dies with no expander system.

 

[Charlie98]

I’ve heard people will trim after M die expanding, but I never tried that. I figured it better to trim after sizing.

That would require a solution in the other direction... a pilot bigger than standard to accommodate the larger than normal diameter flare. Granted, it may just be a .001" or two. In my case, .348 brass is pretty thick, nothing like, say, .30-30 brass... which is paper thin compared.

 

[Varminterror]

It’s been well covered here - if you’re universal decapping before cleaning, then you don’t need the decapping pin left in the sizing die when sizing. Maybe you want the added insurance to know you didn’t miss decapping any case, or don’t have pins or cob stuck in your flash hole, maybe you don’t. Whether you need the expander ball in your subsequent sizing process is independent of the need for a decapping pin on the end of the ball. If you still need the expander ball, SOME dies allow the pin to be removed from the decap & expand assembly. In other dies, you’d have the option of cutting the tip off, or just leave well enough alone. But recognize, in process, you WILL want some kind of expander if you’re using standard sizing dies, as standard sizing dies almost always grossly undersize the neck, then the expander ball pulls it back up to more appropriate ID. You do have the option to send your die to the manufacturer or a machine shop to have the neck honed to fit your desired neck tension for your batch of brass, or you could buy a bushing type sizing die - or you could mandrel expand in a subsequent step. Some sizing dies offer a “pass through” button to hold the decapping pin without expanding the neck upon withdrawal, so you could even keep the insurance of clearing the flash holes with a decapping pin without the burden of expanding with a button. Lots of options.

Personally, for almost all of my rifle loading, I universal decap and I use bushing dies and mandrel expanders to set my neck diameter, so I do not have the decap & expand assy left in any of my dies.

 

[JFrank]

@Varminterror said
if you’re using standard sizing dies, as standard sizing dies almost always grossly undersize the neck, then the expander ball pulls it back up to more appropriate ID.

SPJ vvv
Yeah it’s very violent procedure.

 

[Metal God]

So- Suppose that this is your process. First you only deprime a rifle case, like 556, in one step and then later in your processes (after say cleaning the primer pocket) you size it, you need to leave the depriming pin in to size mouth of the case on withdrawal from the die

Any further reason?

What would be result if you entirely withdrew the depriming pin and its rod assembly from the die and then you resized the case?

That is what I do , I deprime with universal decapping die . Wet tumble then size without decapping pin .

I do something similar with hand gun brass but I actual hand prime my cases before running the cases through all stations on a Lee CTP . I just have my decapping pin/rod removed from the sizing dies .

 

[dh1633pm]

I leave it in. Two reasons. First, I will loose it. Second, is it takes effort to remove it so why not just leave it there. Lastly, when a stainless pin or other foreign object is in the flash hole it will remove it or let me know something is there. Yes, I use a decapping die to remove primers prior to cleaning.

 

[FROGO207]

I also decap with a Lee universal decapping die and wet tumble as a first step. I leave the decapping pin in the die just cause I am lazy LOL. Also sometimes I just decap my brass and reload it without cleaning, usually when working up loads at the range with my hand press. Don't have to worry about forgetting that pesky decapping pin that way.

 

[WeekendReloader]

On 30-30... I decap (FA hand deprimer), then clean (wet tumble), then size (LEE dies). I leave the pin in the sizing die to expand the neck back to the right size. Works for me.