Thinking of Modifying a Seating Die

[IDescribe]

Still looking for some clarity on your anvil in your seating die? 

Are both sides flat?  Or is one side concave/hollow, but just too narrow to fit over the nose and get down onto the cone?

[nicky]

One side is flat (SWC) and the other side is concave(RN).

[ReloaderFred]

I'm not sure why you want to do this, Nicky?  I prefer to seat with the seating stem contacting the nose of the bullet, and even better, perfectly fitting the nose profile, but still contacting the nose.  This gives me more consistent OAL.

Hope this helps.

Fred

[IDescribe]

The premise behind seating off the cone or ogive is that it allows that the closer to the outer diameter the downward force is delivered, the more stable it will be, but that by not fitting the nose perfectly, and just contacting on the anvil?s rim, it allows the bullet to shift as it likes  and self-center in the case, thus reducing runout.   

The Forster Co-ax, which is arguably the best single-stage press, barring some high-end arbor presses, doesn?t even have a shell holder, just some ?jaws? that hold the case in roughly the right spot.  The idea is that a little play allows the bullet and case to self-center. Similar principle.

I think that we tend to want to hold everything as tightly as possible when we put these cartridges together in the belief it increases consistency, but since metal flexes and shellplates in particular flex and nothing is trued as the cases and bullet and dies interact, holding things too tightly can carry the imperfect alignment as the components come together all the way through the process  ? so more runout. 

I have no idea if any of that means diddly squat at pistol distances. 

Added bonus ? for those bullet types where variation in bullet length occurs primarily at the nose, seating off the cone/ogive produces more consistent seating depth than does seating off the nose.

[Wobbly]

Thoughts...

? I have cut some special anvils to seat off the shoulder of a SWC. This allows me to have the same amount of lead protruding from the case on each round. 'Yes', the OAL varies a bit, but this round chambers by landing on that exposed lead "corner". So for consistent feeding, I figure the placement of that shoulder (relative to the case mouth) is more important.

? BUT.... the big part of seating is centering and making sure the bullet goes into the case VERY straight. In this way the chances of the bullet's axis of rotation lining up with the case's axis is much greater. This becasue the bullet can't fly straight if it isn't centered up in the chamber to begin with !

Now some people would accomplish this centering and straightness by pushing with a flat anvil on the meplat of the SWC. A better way is to use a SWC seating anvil (such as Dillon supplies) so that the flat does the straightening, and the conical corral accomplishes the centering. (It's that conical corral that leaves the ring mark on the bullet's ogive that Nicky is talking about.) But sometimes Dillon's anvils are a bit too generous to effectively center the SWC. It's highly bullet brand dependent.


? So my approach is to push straight in on the shoulder, but also to provide a conical corral that captures and centers the lower portion of the conical ogive. In this way I accomplish a consistent exposed shoulder dimension, straightness, and centering.

Hope this helps. 

[ReloaderFred]

I fully understand all this, and have for many, many years.  That's why I prefer to make my seating stems conform to the shape of the bullet I'm using.  It's also why RCBS offers seating stems for certain bullets, i.e.; their seating stems for Gold Dots.   I do this by several means, including epoxy and/or shaping the seating stem to the contour of the bullet in a lathe, or even on a drill press.  That way, the bullet is properly aligned as it's being seated, and I don't get that unsightly deformation on the ogive.  It also prevents the flattening of the nose of the bullet, or the closing of a hollowpoint.

Hope this helps.

Fred

[Wobbly]

In the forest, there are only stick and leaf houses.

When it comes to modifying the seating anvil we all work with the processes and materials we have near us. There's no "right way", only the resources we have available at the time.

Yoda would have something to say about this very topic. 

[Wobbly]

OK, modified 38 Spcl anvil and new 45ACP anvil optimized for 200gr SWC on their way. I'll leave the report and photos to Nicky.

 

[nicky]

Thank you Wobbly. You went far beyond what you offered to do.

Now my friend you have forced me to find an app to host pictures.

[painter]

Thank you Wobbly. You went far beyond what you offered to do.

Now my friend you have forced me to find an app to host pictures.

We all need to climb into the 21st century.

[Wobbly]

Now my friend you have forced me to find an app to host pictures.

Google photos. It's free.

[nicky]

I received the 2 inserts today. They look great. Wobbly did an assume job on the 45 SWC insert. Hope to test them out Sunday morning.

I will post pictures as soon as I find enough courage to dip my toe into the 21st Century 

That darn Photobucket. Just when I was getting the hang of it.

Thanks again Wobbly.

[Wobbly]

How about this....






Look at the expanded photo in Google Photo. Then, RIGHT CLICK on the photo and select "Copy Image Location" off the menu. Then come back to the CZ Forum and click on the Mona Lisa icon at the top of the page. Then Paste (keyboard command Ctrl-V) the copied web address between the 2 HTML commands; that is, NOT inside the brackets, but between the 2 sets of brackets. Your photos will appear within your message just like above.

We'll bring you kicking and screaming into the 1990's yet ! 

Try it. 

[nicky]

I posted it using a I-Pad. Probably would have worked out better using my computer.

Living and learning.

It's 1990 already?

[Wobbly]

I hate cutting and pasting on the iPad. Yes, this is better done on a computer.

Also, the links you gave reveal some of your personal information. That's not a good thing. Much better to simply post the photos. Try it again... right here... right now.