~ Seater die problem . . .

[6hold]

At the risk of sounding a bit daft I have to ask, does all RCBS seater dies have some sort of crimp incorporated into it?
I mean like a taper crimp or roll crimp in the seater die. I have a 9mm seater die that I can’t get to close the slight flare of the case mouth after I seat the bullet. The printing on the seater die reads:

RCBS ~ 9MM ~ LU ~ SEATER ~ #3 ~ 79

What does the (LU) (#3) and (79) mean?​

I can see a slight “shoulder” almost at the top on the inside of the die but it doesn’t seem to do anything no matter how I adjust it. The seated bullet comes out with the flare still there. I have some RCBS info that came with my other die sets somewhere but I can't put my hands on them right now. Any help on this is appreciated.​

 

[DukeInFlorida]

The fast answer is YES.... Most of the "standard" THREE die sets DO include the crimp function in the seating die.

However, the four die sets from most of the manufacturers differ from the three die set in that they separate the crimping function from the seating function. The crimp would be in the fourth and final die.

I'm guessing (without being certain) that the #3 refers to die #3 of a set of four, and that it's a four die set, and you are missing die #4, the crimping die.

Which would explain why there's no crimping function.

Is this a USED set that you got somewhere? What does the end of the plastic box that it came in say?

Rust, corrosion, and missing parts are a common problem with used die sets.

I know you have been posting for a LONG time. But you are obviously NEW at reloading, since your question is a basic, and fundamental one.

You are also probably MISSING a whole bunch of other stuff (knowledge) that you should know.

Perhaps a reloading class would help you get on the fast track.

 

[6hold]

The fast answer is YES.... Most of the "standard" THREE die sets DO include the crimp function in the seating die.

However, the four die sets from most of the manufacturers differ from the three die set in that they separate the crimping function from the seating function. The crimp would be in the fourth and final die.

I'm guessing (without being certain) that the #3 refers to die #3 of a set of four, and that it's a four die set, and you are missing die #4, the crimping die.

Which would explain why there's no crimping function.

Is this a USED set that you got somewhere? What does the end of the plastic box that it came in say?

Rust, corrosion, and missing parts are a common problem with used die sets.

Thanks Duke for the info. You are correct about my getting the 9MM die set second hand. The set is what I’d consider in pristine condition though, absolutely no blemishes whatsoever and no signs of use. The RCBS box is in “well used” shape with the info missing from the end. The tab is also broken that locks the cover closed. It almost looks like they put new dies in an old box.

If the set does indeed need a fourth “crimper” die, well I think I’d just as well buy a new set but this time make it carbide, which this one isn’t.

As for new to reloading . . . I’ve reloaded in the past, about twenty years ago and am now, ever so slowly, getting back into it again. I have reloaded; 38 - 357 - 45ACP - 30-30 and 30-06 without any problems like I’m experiencing with this 9MM set. I think I’ll email RCBS and see if they have the “crimping” die that I may be missing, can’t hurt to ask.

Do you have any guess at what those other printings on the die represent? The (LU, 79) you’re probably right that the #3 is the number of that particular die in the set. Thanks again.​

 

[NavelOfficer]

If you flare anything but very slightly, many roll crimpers do not contact the case adequately to restore the flare to original dimensions. I rarely use the roll crimp, but on full-boat magnum loads with magnum powders (H110, W296 etc.).
You should seat your bullets w/o any contact with the internal crimp. Taper crimp to remove the flare, then roll crimp in a seperate step, if required. Otherwise you end up with a round that binds as it attempts to be inserted into the cylinder or chamber because the hump where the flare hasn't been removed. (As a matter of fact, I just demonstrated this to a new reloader last night. Some of his flared and roll-crimped .38 Special cases wouldn't drop into the revolver cylinder because the "hump" was not removed adequately.)

 

[DukeInFlorida]

9mm will usually require a taper crimp.

From experience with students, if they over bell mouth the brass, it is difficult to get into the crimping die.

There's a test for how much is the right mount of bell mouthing. I cover that in the class.

 

[saltydude]

Can't imagine the (LU) standing for something other than Luger but I could be wrong.

 

[NavelOfficer]

9mm will usually require a taper crimp.

From experience with students, if they over bell mouth the brass, it is difficult to get into the crimping die.

There's a test for how much is the right mount of bell mouthing. I cover that in the class.

Yes... no cartridge that headspaces on the mouth (most 30 Carbine, 9mm, .45 ACP, et al) would get a roll crimp at all.
Usually an over-flared case doesn't even make it into the seating die...

 

[6hold]

Thanks for your take on this folks.
​

If you flare anything but very slightly, many roll crimpers do not contact the case adequately to restore the flare to original dimensions. I rarely use the roll crimp, but on full-boat magnum loads with magnum powders (H110, W296 etc.).
You should seat your bullets w/o any contact with the internal crimp. Taper crimp to remove the flare, then roll crimp in a seperate step, if required. Otherwise you end up with a round that binds as it attempts to be inserted into the cylinder or chamber because the hump where the flare hasn't been removed. (As a matter of fact, I just demonstrated this to a new reloader last night. Some of his flared and roll-crimped .38 Special cases wouldn't drop into the revolver cylinder because the "hump" was not removed adequately.)

I would only use a taper crimp just enough to bring the casing mouth back against the bullet.
​

9mm will usually require a taper crimp.

From experience with students, if they over bell mouth the brass, it is difficult to get into the crimping die.

There's a test for how much is the right mount of bell mouthing. I cover that in the class.

I just bell the casing enough that it doesn't interfere with the bullet starting into the case.​

Can't imagine the (LU) standing for something other than Luger but I could be wrong.

You're right, that must be it "LUGER", I feel like a sap for not recognizing the obvious. The "79" could mean the date of manufacture I guess​

Yes... no cartridge that headspaces on the mouth (most 30 Carbine, 9mm, .45 ACP, et al) would get a roll crimp at all.
Usually an over-flared case doesn't even make it into the seating die...

Agreed, I would only taper crimp enough to bring the casing back against the bullet

Well it would cost me about $23 to get a new taper crimp, seating die for my non carbide set so I think I'll go with the new 9MM carbide RCBS set for $39 at Midway. I wouldn't have to lube each case before sizing (which is a pain in the azz to me). I'm trying out the Lee Hand Press and I think it would be easier sizing with carbide, some of the casing are a bugger to size even with lube on them using the regular steel dies. Ah, I guess time will tell.

I'm trying out the Lee Hand Press because of the lack of room here to set up my RCBS Rock Chucker and Dillon Square Deal. I'm also shooting much less than I had in the past so I wont need volumes of ammo to practice with. I can even get some of the reloading done at my leisure while watching the Pats take apart the Steelers . . . I HOPE!! ​

 

[NavelOfficer]

That hand press will work.
I loaded for the first few years and thousands of rounds with a Lyman handi-press and wore out at least two of them. A bit of a chore doing rifle case resizing, but you can pump out worthy ammo just as well with them. You can reload right at the shooting bench, if need be...