Understanding the Redding taper crimp

[Stopsign32v]

Well used it today for the first time. I must say if you're looking for the crimp like the Lee factory crimp it isn't there (that is how I've always gauged the crimp before). It does show marks on the brass where the grease grooves is but other than that...? So how do you tell if it's good or not? Instructions were very vague.

https://live.staticflickr.com/65535/51600379998_e8686c0459_b.jpg (https://www.flickr.com/gp/113193676@N08/e3h6QT)

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[Winger Ed.]

I normally but a small roll crimp on revolver cartridges, however;
If it doesn't have a edge from being belled, chambers easily, and the boolit can't be pushed farther in by thumb pressure- it's good.

[Mk42gunner]

You can measure a taper crimp by using the knife edge of your dial calipers. Measure once right at the end of the brass, then again about 1/16" down. If the measurements are the same, screw the crimp die in another quarter turn and try again.

Robert

[country gent]

A simple gage can be made from a nut or heavy walled tubing. Its a tube with 2 square ends the bore is bullet dia+ .010- +.015 with a chamfer cut in one end, a countersink does well.
Set on a sized case and measure with calipers, this is your base measurement or zero. From the straight square case mouth. I like to fce the back side to where this dimension is case length + 1" on the measured case. Now all the crimped loaded rounds can be measured If + dimension then bell expansion is still there if minus its got some crimp the more - the more crimp. This gage will show both taper and roll crimps as a comparative measurement. They are dependent on bullet dia not the actual cartridge

[gwpercle]

We were taught to test a taper crimp with "Thumb Pressure" or pressing the boolit nose against the edge of the reloading bench and see if it moves inward . Measuring with a micrometer ? Good Luck with those measurements .
A good press on the bench or press with the thumb will quickly tell you firm the crimp is .

On heavy recoilers...if the boolit has a "Crimp Groove" you will be better served with a good roll crimp into the crimp groove ... trust me on this one .
Gary