Jimbo357mag said:
That may be fine on a 9mm but the OP is talking about 357mag cartridges. I would make sure there is a good crimp on those cartridges for ignition
Hi,
Jimbo, I think the discussion took a slight twist because the OP had purchased a taper crimp die, and a lot of us just don't think of taper crimps for the .357 Mag or other revolver cartridges.
Apparently, Berry's is in agreement, as they addressed the crimp question in their FAQs when someone asked about the lack of cannelure on Berry's bullets:
"Question: Why is there no cannelure in your bullets?
"Plated bullets are very difficult to cannelure, it requires an extra step after the plating process and if not done carefully, can ruin the plating. We only put a cannelure on two bullets (45-70 and 500 S&W), you shouldn't need a cannelure on our other bullets. If you feel the need, you can use a snug roll crimp to keep bullets in place. Just ensure you don't get the roll too tight, such that it severs the plating and destroys the bullet."
https://www.berrysmfg.com/faq.aspx#FAQ8
An earlier question also addresses crimp and how much to apply:
"Question: Do you have load data available? COL or OAL?
"We do not research or publish the load data...
"We recommend a light crimp on the bullet, just enough to put pressure against the bullet without denting or deforming the plating. If you were to pull the bullet out of a case with the proper crimp you would find no more than a scratch on the surface of the plating. If you are denting or deforming the bullet, your accuracy will suffer and the bullet may start to tumble before it hits the target."
https://www.berrysmfg.com/faq.aspx#FAQ3
I dunno about how hard it is to put a cannelure on a plated bullet. I used West Coast brand plated bullets in the .38 Spl/.357 Mag for several years, and they were cannelured. They worked nicely when loaded with mid-range cast bullet recipes and just enough crimp (in the groove) to eyeball. I believe that while the company is now called Extreme Bullets, their bullet designs remained the same. Someone may correct me on that.
Otherwise, note Berry's suggests a roll crimp despite the lack of a cannelure, and what's "just enough" or "too tight" seems to be left to the reloader to determine on his own. The same experimenting to find the "sweet spot" probably applies to the taper crimp for revolver use just as it does for auto cartridges. In other words, start with nothing, work up in small increments until the results start to deteriorate, back off a little and go shooting!
Rick C