Stepped cases

[Walkalong]

Two stepped cases got by me, got primed, and made it to the expander die while loading .380 just now. I don't size while
loading, so it makes it easier to feel stuff out of whack with the expanding, seating, or crimping if done in a second step.

The bullet won't seat that deep, so it wouldn't make it worse, but I need to seat a bullet and see if it will go into the chamber.

I caught them when they felt different getting expanded.

 

[MEHavey]

. . . . stepped cases

I hate ^ those ^ things....

 

[Charlie98]

The expander button hit the step?

 

[FROGO207]

Yep they are in 380 and 9MM so far but havent found them in other caliber brass yet. Ever vigilant for a new one though! And I thought looking for small primer holes in brass that traditionally used large primer holes was a pain!!
It takes an extra step/punch to make those cases. You would think the manufacturer would skip the extra step/process just to save money, but guess thats why I don't make brass cartridges for a living.

 

[Show Me]

So they were made that way or what is that ?

 

[Rimfire McNutjob]

What is the point of the step? Is it to produce a more resilient case head for all of these guns with unsupported chambers? Is it to allow them to use less powder to achieve a certain velocity in their factory ammo?

I've not run into one but I'd be curious as to how much water capacity the step takes up compared to a normal case. Can you imagine if you dropped a normal load of something like Red Dot in there and hit 60k+ PSI due to the reduced "boiler room" volume?

 

[jmorris]

I have found a properly set powder check die will detect the difference in internal volume of the stepped case.

Dillon powder check sensitivity

www.youtube.com

 

[Charlie98]

What is the point of the step? Is it to produce a more resilient case head for all of these guns with unsupported chambers? Is it to allow them to use less powder to achieve a certain velocity in their factory ammo?

I've not run into one but I'd be curious as to how much water capacity the step takes up compared to a normal case. Can you imagine if you dropped a normal load of something like Red Dot in there and hit 60k+ PSI due to the reduced "boiler room" volume?

That's my guess.

9mm, and .380ACP for that matter... are very sensitive to case volume, introducing a stepped case inadvertently would certainly be an eyeopener... and not in a good way. That's one of the reasons I stick with known headstamps, and automatically discard the rest. Granted, that's not always a guarantee, either... *cough, cough* small primer .45 cases *cough, cough*

 

[tightgroup tiger]

I have my powder check die set to pick up a 380 case while loading 9mm. I sort my brass so those stepped cases all go in the mixed brass container and I don't have to deal with them. That container is about ready to be dumped in the recycle bucket.

 

[lightman]

I hate ^ those ^ things....

Me too! Not someones better idea!

 

[Rimfire McNutjob]

That's my guess.

9mm, and .380ACP for that matter... are very sensitive to case volume, introducing a stepped case inadvertently would certainly be an eyeopener... and not in a good way. That's one of the reasons I stick with known headstamps, and automatically discard the rest. Granted, that's not always a guarantee, either... *cough, cough* small primer .45 cases *cough, cough*

So at some point in the not too distant past, the 1/2 ~ 1 grain of powder they save is worth more than the added cost of the additional brass material plus the added weight to shipping.

 

[higgite]

I have found a properly set powder check die will detect the difference in internal volume of the stepped case.

Dillon powder check sensitivity

www.youtube.com

Same here with a 9mm RCBS lockout die. Can't comment on .380, though, as I don't load it.

 

[Walkalong]

The expander button hit the step?

Yes

 

[9mmepiphany]

What is the point of the step? Is it to produce a more resilient case head for all of these guns with unsupported chambers? Is it to allow them to use less powder to achieve a certain velocity in their factory ammo?

There has been a lot of conjecture about why they exist. It obviously isn't to save money as it requires more brass and additional machining.

The most reasonable explanation I've heard/read is that it was introduced to prevent bullet setback.

I usually encounter them when folks have been shooting ammo factory loaded with 115gr or 124gr bullets. I've come across a lot of these cases, of various headstamps, and have never found one factory loaded with 147gr bullets

 

[WeekendReloader]

I'll sort the stepped cases into a separate container and load them in a batch when I have enough. I then use them where I expect to lose the brass. I haven't had an issue using them with plinking loads. My LEE PTX die does not hit the step when expanding.

 

[Slamfire]

When I look at a stepped case, I believe it has to be so the bullet is not stuffed in the case during feed, or handling.

Stepped Cases​

 

[Rimfire McNutjob]

Wasn't that the purpose of the cannelure half way down on some revolver cases like older 38 Specials? Which reminds me of that 38 Special case separation at the cannelure in that other recent thread.

In that regard, I suppose a step is more effective. Given the picture, it seems to not be taking up a vast amount of internal volume. I pictured it as more substantial.

 

[9mmepiphany]

In that regard, I suppose a step is more effective. Given the picture, it seems to not be taking up a vast amount of internal volume. I pictured it as more substantial.

It only became an issue when long bullets like the 147gr came into popular usage combined with shorter throated CZ pistols

 

[jmorris]

When I look at a stepped case, I believe it has to be so the bullet is not stuffed in the case during feed, or handling.

Stepped Cases​

Oh, you let one good one go...,

That would be my assumption. Less worry about neck tension, lower standards = less cost.?

 

[GeoDudeFlorida]

What is the point of the step? Is it to produce a more resilient case head for all of these guns with unsupported chambers? Is it to allow them to use less powder to achieve a certain velocity in their factory ammo?

I've not run into one but I'd be curious as to how much water capacity the step takes up compared to a normal case. Can you imagine if you dropped a normal load of something like Red Dot in there and hit 60k+ PSI due to the reduced "boiler room" volume?

Maybe to prevent setbacks? A box of ammo on a shelf isn’t being compressed much. A box of ammo on the bottom of a pallet at the bottom of a stack of pallets hitting the ground after being dropped from 20,000ft on a cargo skid…?

 

[BiknSwans]

Same here with a 9mm RCBS lockout die. Can't comment on .380, though, as I don't load it.

My RCBS lock out die also has caught stepped cases. Now the Lyman neck expansion/flaring die catches the stepped cases before they get to the powder measure and lock out die. Both stop the press, and I can't pull down the handle.