Some News I Got From RCBS

[JDinFbg]

I recently contacted RCBS about the standard expander diameters they make and have available for 45 caliber pistol cartridges (like 45 ACP and 45 Colt) and whether the expanders have a flair taper or stepped taper at the top the expander. The response I got from RCBS noted:

"In 2010 we changed all the expanders to the “stepped” style expander, which provides a bit of a smoother opening and flare for the brass mouth."

I found this interesting since all my 50 year old straight wall pistol cartridge dies have a flair taper at the top of the expander. In case I'm the only one out there that didn't know this, I thought I'd pass the info along.

 

[GW Staar]

Typical RCBS marketing.....great products when you find out about them 2 years later. They also supply an "M" style expander with their Tube Rifle Bullet Feeders. Marketing or lack of it drives RCBS engineering crazy.

 

[AJC1]

I load more than my share of lead and their pistol dies seem more than satisfactory for the task.

 

[9mmepiphany]

'm the only one out there that didn't know this, I thought I'd pass the info along.

I doubt you're the only one...but then there are a lot of folks who aren't familiar with the difference between the old expanders and the superior M-die profile either.

I really appreciate that both RCBS and Redding now offer expanding dies which feature the Lyman M-die profile

 

[Airborne Falcon]

I have both and am fond of the mandrel expander dies .... but I've often wondered, other than the 45+ cases, does it really make a difference? I love it on 45-70 but the old dies work fine on 45 ACP.

 

[9mmepiphany]

For me the M-die profile does three things which I really like:
1. prevents/reduces shaving of lead/polymer from coated bullets
2. forms a seat with parallel walls which hold the bullet in alignment to start into the Seating die straighter
3. securely holds the bullet between stations on my progressive press...from the Bullet Feeder to the Seating die

 

[JDinFbg]

I have both and am fond of the mandrel expander dies .... but I've often wondered, other than the 45+ cases, does it really make a difference? I love it on 45-70 but the old dies work fine on 45 ACP.

I never really had any problems with using my old expanding mandrills that produce the 'flair' taper for my 38 Special and 45 ACP loads, but I had to make a conscience effort to make sure I got the bullet set squarely on the case mouth. I think the 'step' taper helps assure the bullet is sitting square on the case mouth before running it in the seating die.

 

[Bazoo]

I didn't know that. Thanks for sharing.

I have one set of dies that works with cast bullets using the standard expander. They are RCBS 357 dies. The expander plug is .356 best I recall.

The others 45 auto, 44 spl/mag didn't work and I acquired m dies from NOE. They are both RCBS here too. The 45 dies didn't expand deep enough and the 44 was too small in diameter, even with their cowboy expander substituted. Which was set to me free of charge I might add.

 

[GeoDudeFlorida]

If you load on a progressive, the m-die expander is almost a necessity. If you load on a single-stage, the m-die expander is almost pointless.

 

[Bazoo]

If you load on a progressive, the m-die expander is almost a necessity. If you load on a single-stage, the m-die expander is almost pointless.

It pends on the single stage press. I load mainly on two presses, a Lyman Spartan and a lee hand press. The Lyman at an angle and the lee in hand, the step created by an M die is very useful to get the bullets started.

The main thing I've found useful about NOE expanders is the sizes available for use with larger cast bullets. My 44 NOE expander is .429, whereas the stock one was .426 and the brass swaged my bullets down when loaded.

 

[Kaldor]

I started using a Lyman M-die almost immediately after I started reloading pistol, replacing my Hornady expanders. I tried the Hornady PTX, and quickly figured out I hated it for the same reason I hated the Hornady expander. Then after reading a few different posts, I decided to give the RCBS PTX in my Hornady drop a try and it works exactly like my M-dies. Well worth the money. It bells the case less, but is far more effective.