RCBS Dies

B

Bucksnort1

New member
I just spent the last 30 minutes on perma-hold with RCBS waiting for a technician to answer my question. I became tired of waiting so I hung up. I'm posting my question in this thread.

I have what appears to be a set of older RCBS 45 ACP dies. It's a three die set. I cannot tell you where I got these but it was probably at a gun how, many years ago.

The set consists of a seating die, a sizing die, and a de-capping die. It appears the de-capping die de-caps, re-sizes and bells. I unscrewed the de-capping stem and measured the bottom of the stem about 3/8" inch from the bottom but not at the bottom of the de-cap pin or where the pin is inserted in the stem. It measures .466". Then, I measured at a point just below the threads and found it to be .470" or somewhere thereabout. The sizing die has nothing in it. You can look through it. I has treads at the top as if something was screwed into the die but, if there is, I do not have it.

I have used the de-capping/sizing/belling die and the seating die to successfully load 45 ACP rounds. I can adjust the bell by screwing up or down on the stem.

My question is. Was this a common practice to have the de-capping die perform three functions or am I just lucky the de-cap stem is tapered and bells the cases? Frankly, I like the idea of one die performing three functions.
 
The decapping pin is supposed to be screwed into the sizing die. I don't know of an RCBS set that does it differently, but I am always prepared to be wrong. I expect someone moved things around before selling you the set. Call RCBS or send the dies to them and they will put them right.
 
It appears the de-capping die de-caps, re-sizes and bells.
Click to expand...

Interesting concept, but I don't understand how a case could be resized and then belled on the way into the die and not have the case mouth resized again, removing the bell, on the way out of the die.

Edit: I'm guessing that one of the dies is an expander die with the expander plug missing.
 
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Higgite and Unclenick, Both of you are probably right. The de-capping stem will not screw into the sizing die. I am waiting for a call from RCBS.
 
Probably swapped from something else, then. Let us know how it turns out.

If one were not using a hollow expander die for powder, one could put a decapper in it, but I have no clue what the advantage would be.

Does the sizing die have a carbide ring at the mouth? I am wonder how old the set is.
 
Poggybait......It appears that you are a bit confused.....I too have some old RCBS dies. The resizing die does not have a center pin. First you run the case into the resizing die and it forms the outside of the case. Next you use the decapping die which removes the primer and sizes the inside of the neck and if adjusted correctly bells the case mouth.

These older dies use a decapping pin with a stepped shoulder.

The seating die for .45acp in an old RCBS set can be either a taper seat or a roll crimp. It could well be that you only have three dies of a four die set too as some sets had both seating dies.
 
Back before most of the people of the forum were alive, a three die set consisted of:
1) sizing die
2) expander/decapper die
3) seating/crimp die
You have one of these sets.
The sizing die became the decapping die when progressive presses became popular.
 
Yep, noylj and hartcreek have it. That's the way RCBS dies use to work back before there was dirt but I prefer the new fangled system. We use to have to lube pistol cases back then too. I still have an old steel set (non-carbide) of 38 Spcl dies somewhere around here. The other posters are too young to know.
 
hartcreek and noylj,

By what the two of you are saying, my set is complete and the de-capping/expander die will place a bell at the mouth. Is this correct?

As I said earlier, I have loaded some test rounds with this die set but to be honest with you, I can't remember if I used all three dies or only the de-capper and seating die. The test rounds functioned properly.

A few days ago, I ran some cases through only the de-capper, which placed a bell at the mouth then, I seated one 200 grain, LSWC bullet. It appears to be seated with the proper resistance. I cannot push the bullet any farther into the case with my finger or by pushing it against my desk. Well, I see a problem. I just tried inserting this test case in my AMT Backup 45 ACP. I had a hard time racking the slide to eject the cartridge so using the sizing die is in order; however, when I removed the magazine, I could easily rack the slide. Tomorrow, I will disassemble the AMT and use the barrel to test the round byi hand.

Well, at least I have the answer to my belling question.

When I look through the seating die, I do not see how it can create either type of crimp but I guess it doesn't take much of a taper in the die to remove the bell. I do have a Lee factory crimp die.

I see a new set of 45 ACP dies in my very near future. This is the only die set, all are RCBS, I have with these features.
 
As I stated in my first post it could well be that you have three dies of a four die set. If the label is still on the box what does it say?

In any case these old dies still can be used in a progressive press the dies just have to be inserted in the right order and a powder drop die used.

Since your box indicates that it is a three die set then you have all the dies. If you can not see the shoulder for the roll crimp then you must have a three die taper crimp set. I own a couple RCBS sets that are four die sets with both a taper seat and a roll crimp so I know RCBS produced them.
 
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My RCBS three die sets works as follows:
first die deprimes and resizes the case back to original size
second die bells case mouth
third die seats and applies crimp

My dies are all 30+ years old
 
Yup. "Old School" dies. Progressive presses came along and everybody wanted to go to "powder through expander". Can't do that if you're de-capping with the expander.

The reason it was the way it was...

1. Size
2. Expand/de-cap
3. Seat/crimp

is it was cheaper. An expander / de-capper was cheaper than two separate center spindles, one de-cap, one expand. It was the same amount of work to the reloader either way.

In reloading they are always trying to combine two steps if possible to save effort. When progressives came along it changed the way they could combine steps because they introduced the powder charge into the die set.
 
Sounds great, one of the first progressive presses had 5 positions. One was used for the case activated powder measure, but before that they made the same press without a case lack out.
 
Back before most of the people of the forum were alive, a three die set consisted of:
1) sizing die
2) expander/decapper die
3) seating/crimp die
Click to expand...

So how did all of mine arrive differently? (see my post above)

First die decaps and sizes, second only bells, third seats and crimps...

I'm missing something here...........
 
The sizing die has nothing in it.
Click to expand...

The RCBS expander die has an expander that screws into it for adjustment, useless without it. You may find alternate sizes available to accommodate lead bullets or jacketed.

I think there is confusion about the decapping die doing any belling. As has been pointed out, I can't imagine how it would be possible to size the case and then withdraw it with a flared mouth. The expansion and belling would occur if you had that expander part for the next die station.
 
I'm missing something here...........
__________________
Click to expand...

No, unless you plan on adding powder. I do not use a progressive press without a lock out die. With 5 positions I can not miss, with 4 I find it is difficult to seat and crimp on different positions when using a lock out die or a powder die.

F. Guffey
 
When I got my first progressive (a Hornady as Dillon only had a 4-station press at the time), set-up was:
1) size/deprime (had to get new die sets)
2) expand
3) charge case (powder-through expanders did NOT exist yet)
4) seat
5) crimp
Really, you have to go back 30-35 years.
The first RCBS carbide sizing dies had little if any bevel and you HAD to exactly align the case and die and you had to use a couple of fingers to help feed the case into the die most of the time.

>So how did all of mine arrive differently? (see my post above)

Maybe your dies aren't over 40 years old?
 
There is nothing wrong with the 40 plus year old dies and it was NOT just RCBS that did the steps differently back then so if you purchase used die sets you have to pay attention to detail. When I see old dies that I want I disassemble them and see what each die does.

I was working up some 7.62x39 a few weeks back with my Lyman dies and was breaking decapping pins. I converted the decapping die to use a RCBS decapping stem and when I did that I found the problem.....Lyman had bored the decapping threads off center. I went to my LGS that sells used die sets and he had another rifle Lymen set. I just swapped out the threaded cap that the decapping rod thread through and I was back in business with the decapping pin centered.
 
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