seating swages .454 to .450 How to stop this?

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I just got them in the mail and am heading out to my reload area to test them out.

More to follow.

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Well, that didn't take long.
25 minutes

The new RCBS stem is the exact size as the standard one I got with the die. The stem is not marked and neither was the plastic bag it came in. Someone must have grabbed the wrong one at shipping.

Really nice RCBS folks in Oroville. It must have been the dam breaking that made these folks realize the important things in life. Really nice to talk with.

This is my fifth week trying to get my .454 bullets to stay .454 after being seated. Went from Redding to Lyman and now at RCBS.


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RCBS came thru on that last try. They sent me two stems to try, one of which was the .454 i have been looking for.

There is now a perfect little nest that I can just barely hand push my .454 bullets into without swaging down. The crimp should keep them intact until the pressure builds.

Range report to follow.

 

[historicfirearms]

Along with the problems already mentioned and dealt with, your seating die may also be sizing down your cast bullets. I've had this happen with Lee 45 Colt dies among others. I've also applied too much crimp before which was detrimental to accuracy. Now I crimp just enough to prevent bullet creep in recoil, and do it in a separate step from seating.

 

[Clovishound]

My one experience with RCBS customer service was less than stellar IMO. It was cheaper and quicker for me to just buy another die by another manufacturer, than to ship mine back to RCBS and have them figure out what was wrong with it. They didn't seem terribly interested in solving my problem.

 

[kooz]

I have a 25-5 also with .460 throats . I sent it off to S&W to be fitted with a new properly spec'd cylinder , should be done in a week or two . Now that they have introduced the M-25 classic , they have good cylinders available. While there I had some other work done, but the cylinder portion of the work was very reasonable , I want to say it was only $92 for the cylinder and then a little labor to have it fit to the gun .