RCBS 9mm dies

[Grassman]

Jumping into pistol loading and had a question about the RCBS 9mm die. The seater die comes with 2 different stems? What for? One is marked RN and the other is marked TMJ. Come someone explain this to me. Thanks

 

[Galil5.56]

They are of a different profile that corresponds to the type of bullet used so that nose damage is minimised and the bullet seats straight. RN for round nose, TMJ for their total metal jacket style, and also for TC (truncated cone) style bullets.

 

[Grassman]

Which one would hollow point fall under? Is this something unique to 9mm, my .40 S&W only has one.

 

[Walkalong]

RN for hollow points, although it may not fit it just right. The other seater stem is flat in the middle with a small edge and works well with WC's, SWC's, etc.

A more rounded stem with a deep middle is best for HP's and will push on the ogive with little damage to the bullet, especially the leading edge of the hollow point since it is not contacted.

 

[Grassman]

That leads me into the next question, I got a little ring around the bullet after seating. Is this common or are more die adjustments needed? Its not real bad, just a little unsightly. More or less taper crimp?

 

[rfwobbly]

I got a little ring around the bullet after seating.

I assume you mean a ring on the exposed nose of the bullet (as opposed to a ring left around the waist of the bullet from the crimp). Try the other seating cup and see if it does better. If you have a lathe you can alter the seater's cup shape to better fit the bullet ogive.

Just ideas.

 

[Grassman]

I tried them both, and they both leave a pretty good ring around the bullet. This is a 147 grain pointed nose bullet. I checked a factory load of the same bullet, and it had a faint ring also.

 

[RidgwayCO]

RCBS's 147gr 9mm TMJ (totally metal jacketed) bullet has a small flat nose that wouldn't seat well with a round nose bullet seating plug, so they include the TMJ seater with the RN seater in their three die set (a pretty good deal).

If you ever have a bullet that needs a specialized seater plug, RCBS will custom-make one for you for a very reasonable fee. You just send them two samples of the bullet you want to seat and a check, and the custom seater plug will be sent to you before you know it (the bullets you send them will be returned as well). Call them before mailing so that you know how much money to send.

I've done this with a couple of bullets that I "stocked up on", and the custom seaters are a joy to use.

(I believe Lee offers this same service, but I've never used it.)

 

[Steve in PA]

The flat is for the hollow points. The flat, open mouth of the bullet will rest against the flat spot in the one seating stem.

The other stem is for FMJ's. If you try and seat hollowpoints with this stem you run the risk of crushing the hollowpoint.

 

[RP86]

If you call up RCBS customer service they will send you out a Gold Dot hollow point seater plug for free, just provide your address. I'm having a similar problem with FMJ bullets being deformed by the seater plugs, but I'll make another thread to avoid hi-jacking this.