Crimping on the flats not the crimp groove

[FISH4BUGS]

I have a Hensley & Gibbs 12s mould that has a neat little light 38/357 bullet.
It does not have a crimp groove, rather you are instructed to crimp on the front driving band a/k/a flats.
Has anyone had any experience doing their bullets this way? Not necessarily with this particular bullet but in general.

[mehavey]

Usually it's crimp over the ogive curvature -- objective is to keep bullet from walking OUT.

I have crimped into "the flat" before -- during seating if soft alloy/light-moderate crimp -- separate crimp to keep from bulging the case if more than just a light-moderate crimp/hard alloy.

Personally, I'd crimp juuuuust short of the flat -- top of grease groove -- and call it a day

[farmerjim]

Why not just put a taper crimp on it?

[John Boy]

And don't 'hog' the taper crimp

[Win94ae]

I crimp wherever the case mouth ends up; that is with handguns or rifles, no matter the type of crimp.

[robg]

with lead boolit i crimp where i need to, crimp groove or not

[gwpercle]

If a boolit has NO crimp groove you have two choices .
1.) Roll crimp over the front driving band edge . Most 38/357 dies will have a roll crimp die .
2.) Taper crimp on the boolits smooth sides aka "flats" . I taper crimp 9mm boolits (with no crimp groove) loaded into 38 or 357 cases by using the taper crimp die from a 9mm luger die set .

Gary

[reddog81]

A very light crimp should work. Too much crimp and the case starts to buckle, not enough crimp and the flare from the expander die remains - you want to be somewhere in-between there.

[Taterhead]

When I load a clone of the HG 68 SWC into 45 Colt cases, I seat so that a crimp can be applied just over the bullet shoulder.

A taper crimp won't do much at all to prevent bullet creep, but would remove the bell. It would work for a low intensity round that otherwise has decent neck tension.

[trails4u]

I crimp wherever the case mouth ends up; that is with handguns or rifles, no matter the type of crimp.

Agreed.

[prs]

Usually it's crimp over the ogive curvature -- objective is to keep bullet from walking OUT.

I have crimped into "the flat" before -- during seating if soft alloy/light-moderate crimp -- separate crimp to keep from bulging the case if more than just a light-moderate crimp/hard alloy.

Personally, I'd crimp juuuuust short of the flat -- top of grease groove -- and call it a day

With tube type magazines, ala most lever actions, the chief idea is to keep the bullet from traveling inward! Applications vary. If crimping on a drive band, a precisely adjusted taper crimp may suit so long as the band is not too narrow. The Lee collet crimp die may be an option here. If rounds are revolver only, crimp where it need crimped for correct OAL to keep the bullets in the case under recoil.

prs

[mdi]

For a SWC w/o crimp groove it is common to seat the bullet with the foremost shoulder/driving band seated a few thousandths below the case mouth and lightly roll crimp over the edge. Crimping on the ogive would need the bullet to be seated way too deep and for use in a tube magazine, use the proper bullet with a crimp groove...

[rockshooter]

I'm with MDI- I use SWC bullets that are heavy for caliber and have to crimp just over the foremost shoulder to be within max length for chamber (revolver)
Loren

[Ozark mike]

I have crimped where i need to but i try to find a mold that will allow me to crimp in a groove. I do not recommend doing this in tube guns where a spring and heavy recoil may allow it to go deeper in the case with smokless.

[Winger Ed.]

I'm a big taper crimp fan.
It tends to be more forgiving for little differences in case length,
and lends itself to crimping where ever the right OAL comes up, and has been better for me than a roll crimp.

[mdi]

FWIW, since 1969 I have been seating bullets to the crimp groove or cannelure and disregarding book OAL (revolver ammo). I found no reason to do different like short cylinders/long bullet combinations and it has worked for me in all my revolvers (9). When I first started I figgered the bullet designers knew their business and located the groove or cannelure in the correct place. I started with the basic "roll crimp in grooves for revolvers, and taper crimp for semi-autos" and that has worked for tens of thousands of rounds with no problems. Of course I've experimented with different types and different applications of crimping (Profile crimping, collet crimping, stake crimping, roll crimping semi-auto handloads, taper crimping revolver loads extra heave and no crimp), but the basics continue to work today. I have no need to use smooth sided bullets in my revolvers and ignore crimp grooves when using cast bullets with grooves in my semi-auto loads. I even experimented by trimming 100, 44 Magnum cases to .001" of each other and crimping using a scale to measure pressure to keep crimps as close as possible and found results no better than mixed brass and crimping by "feel" or against a stop. Perhaps I'm trying to say some aspects of reloading are easily "over thought" and I believe crimping handgun ammo is one...

[jsizemore]

with lead boolit i crimp where i need to, crimp groove or not

What he said. That's why I quit shooting jacketed handgun bullets.

[fcvan]

FWIW, since 1969 I have been seating bullets to the crimp groove or cannelure and disregarding book OAL (revolver ammo). I found no reason to do different like short cylinders/long bullet combinations and it has worked for me in all my revolvers (9). When I first started I figgered the bullet designers knew their business and located the groove or cannelure in the correct place. I started with the basic "roll crimp in grooves for revolvers, and taper crimp for semi-autos" and that has worked for tens of thousands of rounds with no problems. Of course I've experimented with different types and different applications of crimping (Profile crimping, collet crimping, stake crimping, roll crimping semi-auto handloads, taper crimping revolver loads extra heave and no crimp), but the basics continue to work today. I have no need to use smooth sided bullets in my revolvers and ignore crimp grooves when using cast bullets with grooves in my semi-auto loads. I even experimented by trimming 100, 44 Magnum cases to .001" of each other and crimping using a scale to measure pressure to keep crimps as close as possible and found results no better than mixed brass and crimping by "feel" or against a stop. Perhaps I'm trying to say some aspects of reloading are easily "over thought" and I believe crimping handgun ammo is one...

MDI, I agree with 99.9% of your statement. I have a mold my Dad bought for 41 Mag that was a SACEO Keith style boolit. When crimped in the groove, it barely fit the the S&W M57 Cylinder, and absolutely would not chamber in my Marlin 1894C in 41 M. Well, it would if I crimped in the front driving band or on the shoulder. My fix was a SAECO 420 TC mold, which fed well in both the S&W M57 and Marlin 1894C.

So Orygun?, not very far from Crescent City, CA. Heck, we're practically neighbors when I am out west. (still have a house there) :)

[Jack Stanley]

Most of my loading is done with a taper crimp and sometimes the overall length needed means a taper crimp on a flat . It hasn't affected accuracy that I have noticed . It even works with revolver and lever action ammo until the load gets real heavy .

Jack

[JonB_in_Glencoe]

I use a LEE collet style FCD for the purpose posed by the OP. I have the 357M FCD, but I don't believe Lee makes one for 38 spl, but they do custom orders, although maybe not during the covid?

[Larry Gibson]

Crimping on a drive band/flat is perfectly ok if done correctly. I do it with several bullets in several cartridges. Mostly with45 ACP bullets in the 45 Schofield and 45 Colt but there are others times I occasionally will role crimp into a drive band.

First, the alloy shouldn't be super hard as the case mouth must crimp into the ally w/o buckling the case. Up through bullets with BHNs of 14-15 work okay for me.

Second, seating and crimping at the same time most often does not work if there is no crimp groove. Buckled cases and/or alloy will be scraped in front of the case mouth. I seat the bullets to the correct OAL before any crimping and then crimp in a separate stage.

Finally, for crimping, the seat stem is backed off in the seat/crimp die enough so it won't touch the bullet. The seat/crimp die is then turned into the press for the desired amount of crimp. I use a U shaped shim between the die lock ring and the press the right thickness for the die adjustment for crimping. That way the die lock ring doesn't have to be undone and adjusted for each time of use. I simply use the shim to seat the bullets and then remove to crimp. Of course the seated stem still has to be adjusted but a dummy cartridge with the bullet used makes that adjustment quick and easy.

I prefer to use a roll crimp die as it doesn't damage or swage the drive band as much as a LFC die will [collet type for rifle cartridges].

[45-70 Chevroner]

If I were going to crimp on top of a driving band or any where but the crimp grove, I would use a Lee factory crimp die. This would avoid bulging the case.
Larry is right about the Lee FCD, but in my experience it has not affected accuracy.