Any one know the diameter of the expander plug in the 38-357 cowboy dies? I would like to know please. Thanks Bill
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Any one know the diameter of the expander plug in the 38-357 cowboy dies? I would like to know please. Thanks Bill
.357 is the diameter for expanders in the 38-357 cowboy dies. Normally they are .356.
supposed to be a bit bigger so lead bullets will load better.
mine do a fine job when I'm not on my SDB--but that just might be my mind finding a good reason for buying them.
Here is my results with the RCBS Cowboy dies.
Expander Diameter Average of four measurements
Across 4 different diameters.
Regular die .3743 - . 3746 Avg. .37445
Cowboy die .3759 - .3761 Avg. .37560
Difference .0011
Resizer differences
( Average of 10 cases )
( Same 10 cases with each set of dies )
Outside Diameter Before Sizing After Sizing After Expander
Regular RCBS Dies .3773-.3785 .3713-.3725 .3743 - .3746
RCBS Cowboy Dies .3773-.3790 .3715-.3725 .3759 - .3761
Inside Diameter
Regular RCBS Dies .3515 - .3520
RCBS Cowboy Dies .3520 - .3525
Note that after expanding, the maximum difference in inside diameter is 0.0010 The minimum difference is 0.0000
Not only is the expander larger but the inside bullet seating guide diameter is also larger so that you can seat a larger bullet.
I like mine, but they are not radically different from the standard dies. They look real good.
I use a standard set of rcbs dies, except that I substituted the Cowboy expander plug. I believe it is sized .357. It is enough of a difference that my SWC and 360432 358 bullets seat with the right neck tension and they do not swage down smaller. Good results with this setup. I don't see a need for a full Cowboy set, unless aesthetics are an issue.
I do like that the Cowboy plugs come with a brass-colored lock ring so I can easily tell what expander plug is installed.
Do the RCBS cowboy dies do the "M die" thing where it is more of a stepped mandrel than a belled expander? I feel like that is the key to the M die's effectiveness so hopefully they do. The hornady cowboy die set I have for .45 colt seems to by eye but I haven't measured it carefully.
I have the Cowboy dies in .38-40 and .44-40.I have not disassembled them to inspect but they do function like Lyman M dies if adjusted to do so.I like mine.
All I shoot is my own cast. I have a set of the RCBS Cowboy dies for 45 Colt and 30-30. Yep . . they are "pretty" but honestly, when I've used them I don't see a big difference between them and regular RCBS dies for the same caliber. I seem to have better luck with my standard dies which seem to work just fine and I use a Lyman "M" die for both of those calibers to expand with - which also does the job. I know the ID is supposed to be a little more generous as well but so far I've never needed that with the components I use. Others will disagree I'm sure and or course everybody's situation ay be a little different with their cast boolits and their individual gun.
I both mine because I had heard the "hype" about them and they do look really nice - but I probably will never buy another set. YMMV Just trying to be honest about it based on my own experiences.
Yes. The RCBS expanders have been the M style for several years now. I didn't realize that until I bought a pistol set a few years ago and was surprised by the change. I called RCBS to inquire about buying retrofit plugs for my old dies. Of course, in typical RCBS fashion, they took care of me for free. My pistol expander, Cowboy sizes and standard, are all M style
I believe the best way to get proper expansion and correct neck tension is by using the Noe expander plugs that fit inside the Lee Universal expander die and yes they have the step built in like the M-die. Gp