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casullman
02-25-2009, 09:10 PM
how much bell????? all the way to the cannalure???

klausg
02-25-2009, 09:19 PM
casullman-
You want to expand enough to be able to just start a bullet into the case mouth, like about 1/32". Crank your expander stem all the way up and run a sized case up into the die. then crank your expander down until you feel it contact the case mouth. Back the case out and drop your expander about 1/2 turn; run the case in & out and check with your bullet. Continue until the bullet just starts, then sect the lock ring on your expander stem. You'll find that neck tension, (i.e. lots of it, I like to be able to see lube grooves through the brass), has a lot more to do with accuracy than crimp. Your case life also goes south when you over-expand. Hope this helps.

-Klaus

casullman
02-25-2009, 09:53 PM
thank you Klaus proceeding to press imediately

armyrat1970
02-26-2009, 09:27 AM
casullman-
You want to expand enough to be able to just start a bullet into the case mouth, like about 1/32". Crank your expander stem all the way up and run a sized case up into the die. then crank your expander down until you feel it contact the case mouth. Back the case out and drop your expander about 1/2 turn; run the case in & out and check with your bullet. Continue until the bullet just starts, then sect the lock ring on your expander stem. You'll find that neck tension, (i.e. lots of it, I like to be able to see lube grooves through the brass), has a lot more to do with accuracy than crimp. Your case life also goes south when you over-expand. Hope this helps.

-Klaus

I have a universal expander and I go even less than 1/32". When I can visually see the case mouth open a little, that is usually enough. No matter how slight the bell as long as it is not shaving the bullet when seating your fine. The less the best. I like tight neck tension also. Depending on the weapon style there may be no need to crimp if you have good neck tension. I do crimp for my tube feed Marlin Model 1894 so as not to push the bullets back into the case and give a compressed charge if loaded hot.

versifier
02-26-2009, 01:52 PM
It does also depend on if the bullet is jacketed or cast and with or without a gas check. A jacketed bullet needs almost no belling if the case has been properly chamfered. A cast gas check bullet is almost as easy to start, and a plain based cast bullet needs the most, but even then only just enough to prevent any shaving of the lead. Some loaders only chamfer handgun cases when and if they need to trim, a mistake as this only results in the need for more expansion, which works the brass much more than needed, and the necks become brittle from work hardening and start splitting after only a few loadings instead of a dozen or even more if the loads aren't too hot. Revolver cases need trimming so seldom that if they aren't abused, the primer pockets will loosen long before they need their fifth trimming. It is not unusual for me to get twenty or more loadings from a batch of .357 cases if the brass is decent and the loads are light.

runfiverun
02-27-2009, 12:16 AM
i have so many loads on some of my 38's that i am thinking i'm gonna have to anneal them for the next trimming.
i barely flare them and don't crimp them.and only neck size a portion of them.