Taper crimping a cast bullet

[cdet69]

When crimping a lead bullet for a cartridge that heads paces on the case mouth do you use the crimping cannelure or do you use the driving band. This is for a 350 legend bolt action rifle.

[Winger Ed.]

I taper crimp all straight wall cases.

But only enough the case mouth doesn't 'sang'.
The flare is smoothed out, but I don't try to mash it down into some sort of roll crimp something that dents in the boolit like an hourglass.

This works well if the crimp groove doesn't exactly jive up with the end of the case mouth
when determining the OAL for what works best in your gun.

[1hole]

... do you use the crimping cannelure or do you use the driving band. This is for a 350 legend bolt action rifle.

You have probably noted that there is no agreed upon written answer to that question; that's because there is no certain answer.

Taper crimping of straight wall cases is very little crimping. It's mostly done to remove the case mouth flair without them going smaller than the chamber.

Large caliber and powerful revolver ammo benefits from a heavy roll crimp in the provided groove to resist bullets pulling when fired AND obtain the needed start pressure for a consistent burn.

Rifle ammo can achieve the same ignition goal by seating bullets at or even into the lands, even without crimping. Few cast loads for box magazine rifles are heavy enough to cause bullet pulling.

Only YOU can determine which crimping will work best for your rig.

[jsizemore]

My first automatic reload of a jacket 230 gr ball ammo in my SA 1911 set the bullet back in the case. From that moment I shot cast that was taper crimped into the front driving band. It's just enough bite so the round survives the travel up the ramp and has consistent ignition. No ramp in revolvers but the roll crimp is applied to fit into the groove or just bite into the driving band. Bullet doesn't get bounced around and better ignition.
Compare rounds with various stages of crimp fired over the chronograph to see what works and doesn't.

[cdet69]

I’ve reloaded and rifles before. This is my first straight wall case that headspaces on the case mouth and not rim. Thanks for all the advice.

[mehavey]

350 Legend.

1. Determine max OAL that will chamber reliably and fit the magazine -- whichever is the limiting dimension..
2. Taper -- not crimp -- the mouth back to 0.378"... wherever that happens to be

[fredj338]

My first automatic reload of a jacket 230 gr ball ammo in my SA 1911 set the bullet back in the case. From that moment I shot cast that was taper crimped into the front driving band. It's just enough bite so the round survives the travel up the ramp and has consistent ignition. No ramp in revolvers but the roll crimp is applied to fit into the groove or just bite into the driving band. Bullet doesn't get bounced around and better ignition.
Compare rounds with various stages of crimp fired over the chronograph to see what works and doesn't.

That is the issue, a taper crimp doesnt really hold the bullet in place unless over crimped. Proper neck tension is what you want, the taper crimp is just finishing off the loaded round from flaring & seating. Your 230gr ball rounds were 0.451" & probably seated in thin brass like RP.

[Hi-Speed]

I use taper crimp when not crimping in the crimp grooves…

[GregLaROCHE]

A taper crimp can hold pretty well if you want it to. It will never hold like a roll crimp in a cannelure, but I load taper crimped 45/70 in the tube of my 1895 and don’t have any problems plinking with it. However, if I was using it for bear protection, I would be using a heavy load with a good roll crimp into the lead if there wasn’t a cannelure.

[georgerkahn]

You have probably noted that there is no agreed upon written answer to that question; that's because there is no certain answer.

Taper crimping of straight wall cases is very little crimping. It's mostly done to remove the case mouth flair without them going smaller than the chamber.

Large caliber and powerful revolver ammo benefits from a heavy roll crimp in the provided groove to resist bullets pulling when fired AND obtain the needed start pressure for a consistent burn.

Rifle ammo can achieve the same ignition goal by seating bullets at or even into the lands, even without crimping. Few cast loads for box magazine rifles are heavy enough to cause bullet pulling.

Only YOU can determine which crimping will work best for your rig.

Imho, 1hole provided the best answer! Plus, ensure the bullet is firmly gripped by the case so "crimped". Note that this adds credence to using cast bullets ~ 0.001" larger than measured bore.
geo

[mdi]

I don't taper crimp anything. I just use a taper crimp die to deflare semi-auto handloads and roll, profile, or collet crimp everything else...