Hardcast shaving cannelure issue

[pinne65]

I decided to try some coated hardcast for my 10mm/0.40 but I'm having the worst issues getting the finished rounds to chamber. I bought 200/180/155/140 grain bullets. The 200,155 and 140 grainers all have a crimp cannelure and those are the ones that are giving me issues. The 180 grain works just fine. The bullets are .401 diameter. (The copper plated or jacketed bullets I normally use are 0.399 - 0.400). I have Lonewolf 10-40 aftermarket barrell. And normally I don't have any chambering issues at all, be it factory or my own handloads with jacketed/plated.


The cannelure bullets often times seat shaved.



No matter how much I flare the mouth, ranging from barely anything to looking like a church bell where the bullet almost disappears if you drop it in and the case is scratching the walls of the seater die.


Max flare


I understand you have to be more particular about putting the bullet extra straight in the case before seating than with jacketed or plated bullets. But more often than not the cartridges come out like below after trying it in the barrel.


The depth of the mark on the case coincides with the bottom of the bullet below the cannelure. And since that part is already in the case when the seating process starts

/-----\
| |
> <
|____| <----

This is driving me crazy. Any suggestions on how to combat this or what might be wrong are welcome!

Read More

 

[Member 34319]

That is not a crimp cantalure. It is a lube void.

Crimp looks like this, for roll crimps. These also have lube filled lube voids.


How do they shoot? If they shoot fine, don't worry about the shavings.

 

[pinne65]

That is not a crimp cantalure. It is a lube void.
How do they shoot? If they shoot fine, don't worry about the shavings.

10-4 on the lube.

They won't shoot at all though - they won't even chamber properly

 

[Member 34319]

10-4 on the lube.

They won't shoot at all though - they won't even chamber properly

Are you taper crimping to remove the belling after seating?

 

[DizzyJ]

Taper crimp I assume?

 

[jr leadslinger]

Are you seating and crimping with same die ? What size expander are you using for expanding your case's ?

 

[pinne65]

I'm taper crimping in a separate step. Not sure about the expander size. It came with my 10/.40 rcbs carbide die set and doesn't have any markings besides that.

 

[DizzyJ]

I'm taper crimping in a separate step. Not sure about the expander size. It came with my 10/.40 rcbs carbide die set and doesn't have any markings besides that.

What happens if you back off the crimp incrementally? I'd start there and see if that helps. Obviously you want enough crimp to hold the bullet, but not over crimp.

 

[pinne65]

The crimp is already pretty faint. But I'll do some testing and see if it helps. Though I'm using the same crimp setting on the 180 grainers and they work just fine.

 

[DizzyJ]

Is your brass all uniform length? Usually not an issue with a taper crimp, just thinking out loud.

 

[P7M13]

If all else fails, go to Sportsmans, get a cartridge check block (whatever they're called), and use that. You'll be able to look at it outside of a barrel to see WTH is going on. Don't have one for pistols, otherwise I'd loan you mine.

 

[pinne65]

It's not - range pickups, .838-.844.

 

[pinne65]

Might get one of those blocks

 

[jr leadslinger]

Are the shavings showing after seating the bullet and before crimping? or after the crimp ?

 

[jr leadslinger]

IMO if you are getting the shaving in the seating die, the die needs to be back out a turn or so and the seating stem adjusted to desired AOL. If it's in the crimp die it's trying to seat the bullet deeper causing the case mouth to shave the lead.

 

[pinne65]

Shavings were from the seater. Thought for sure I had it far enough out - Thanks!

And it seems I didn't have enough crimp.

Everything looks happy now. I'll run a small batch and see how it goes.

 

[pinne65]

Ok - ran a batch through. It still took some tweaking on th crimper. So I'm wondering how sensitive the crimping process is to case length. I sampled over a dozen and came out with 6/1000" difference in length, .838 - .844. That doesn't mean there weren't any cases longer or shorter though.

It seems like these bullets reveal reloading mistakes

 

[jr leadslinger]

The amount of crimp will determine if the round will chamber i.e. the plunk test. I set the crimp die to just remove the flair then turn the die 1/8th of a turn tighter. And since these are cast boolits you might want to pull one or two down and check to make sure the boolits aren't being sized down which will cause leading.

 

[pinne65]

One observation is that these bullets with the lube grove needs to be placed really straight in the case before the seating step. If not, it seems like the case rim likes to grab the bullet and pull it even more off center.
The hard cast without grove are more forgiving and plated/jacketed even more so.