Crimping Trobles

[terrytm]

Hi:
I am having trouble crimping some very hard bullets (Brinell hardness of 32-35) in 9mm cases.
The problem is the boolits stay loose no matter what I do. I can push them into the case with a little bit of pressure.
I do not know the alloy of the boolits other than they appear to be lead.
I have tried chamfering the cases ae I usually do and I am wondering if I might be better off not chamfering the cases.
I bought 1000 of the boolits at a gun show and would like to use them.
I have tried both the Lee and RCBS dies and different shell holders to no avail.
ANY AND ALL HELP WOULD BE VERY MUCH APPRECAITED>

Thanks,
Terrrytm

[nhyrum]

You're over doing the flare most likely. 9mm, even with cast, you only need enough flare to not shave the bullet, and enough crimp to return the case mouth to size, with maybe a thou or two crimp

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[Bazoo]

Dumb question. Have you measured to see that the bullets are a size conducive to 9mm?

[nhyrum]

Dumb question. Have you measured to see that the bullets are a size conducive to 9mm?True. Check your bullet size. Check the simple things first. Over doing the flare is my bet, assuming everything else is set. Basically what happens is the flare goes deeper than what the crimp does, So the only part of the case touching the bullet is the crimp, because the case will leave an impression on the bullet when crimped too hard then the case springs back a little in size.

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[sparkyv]

Yup...bullets may be undersized.

[fredj338]

Have you actually checked the hardness? No 9mm load needs that hard a bullet. If you are over crimping, the brass may be springing back & the bullet will be loose. Check the expander dia, it wants to be 0.001-0.002" smaller than the bullet. Are you sure the sizer is doing its job? No I never chamfer pistol brass.

[Bazoo]

I can't see how crimping would cause an undersized bullet. Ive crimp the fire out of bullets and not experienced loose bullets as result.

[nhyrum]

Have you actually checked the hardness? No 9mm load needs that hard a bullet.

Oh wow, I just looked at the numbers again... Yeah, hell my 454 casull I don't usually make that hard. If the lead is any common casting alloy, those bullets are going to be fragile as hell and will most likely cause leading in 9mm as the pressures are not high enough to obturate/ form to base of the bullet to the bore.

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[gwpercle]

Hi:
I am having trouble crimping some very hard bullets (Brinell hardness of 32-35) in 9mm cases.
The problem is the boolits stay loose no matter what I do. I can push them into the case with a little bit of pressure.
I do not know the alloy of the boolits other than they appear to be lead.
I have tried chamfering the cases ae I usually do and I am wondering if I might be better off not chamfering the cases.
I bought 1000 of the boolits at a gun show and would like to use them.
I have tried both the Lee and RCBS dies and different shell holders to no avail.
ANY AND ALL HELP WOULD BE VERY MUCH APPRECAITED>

Thanks,
Terrrytm

What diameter are the boolits ?
Information helps get a concise answer ... what boolits are you dealing with ?

[mehavey]

am having trouble crimping some very hard bullets (Brinell hardness of 32-35) in 9mm cases.1. How in the WORLD does one get a BHN35 out of a cast bullet ? (inquiring minds want to know)
2. One does not "crimp" mouth-headspacing auto-loaders. Case friction does it all.
3. One merely smooths out the mouth flair back to SAAMI 0.380" and walks away.
4. What's the actual bullet diameter ?

[nhyrum]

1. How in the WORLD does one get a BHN35 out of a cast bullet ? (inquiring minds want to know)

Copper alloying is one way. Makes them not brittle either. There's a few write ups around, various ways to do it.

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[terrytm]

Hi:
Thank you for your replys.

The boolits are .356 round nose 120 grs. Hi:



Yes, I have tested the hardness and is Brinell 32-35.

I have no ideal what type of metal it is none of the junk yards will test it for me.

Thanks,

Terrytm

[mehavey]

Seat the bullet without any crimp at all.
Is it still loose in the case at that point?

[nhyrum]

Hi:
Thank you for your replys.

The boolits are .356 round nose 120 grs. Hi:



Yes, I have tested the hardness and is Brinell 32-35.

I have no ideal what type of metal it is none of the junk yards will test it for me.

Thanks,

TerrytmEither something is completely wrong with your tester, it those bullets are far too hard for 9mm. At that harness, I can't see 9mm ever being able to develop enough pressure to get lead that hard to even remotely seal and you'll end up with lead in the barrel. If you're using a traditional lube, pick wisely

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[nhyrum]

But anyway, back to the issue at hand. Back off the crimp. Like has been mentioned, cases that headspace(basically the part of the cartridge that keeps the round from going too far into the chamber) of the case mouth, like straight wall rimless cartridges, is important to leave that datum point there. Really any crimp at all will remove it. And, over crimping can date the case to bulge or even crease if extremely excessive.
Seat the bullet without any crimp at all.
Is it still loose in the case at that point?If backing off the crimp doesn't help, back of the case expander, whatever your setup. I know it seems counter intuitive, but this exact thing happens all the time, and it's 99% over doing the case mouth flare.

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[Dusty Bannister]

Have you verified that the cases you are reloading have been correctly sized, deprimed and the correct expander has been used for the 9MM Luger round? Are you sure you have 9MM and not 9MM MAK cases? Have you verified by measuring with a micrometer that the sized bullet is actually .356"? The hardness of your cast bullet is unusually hard so what method or test tool did you verify the bullet hardness. If it was the LBT hardness tester, that is getting pretty close to the end of the hardness scale. Have you verified the accuracy by testing against a known pure sample of Linotype? LBT has some specific instructions for preparing the bullet sample which includes the dwell time while the load is applied to the sample before reading the hardness.

It will be really helpful if you will take a small sample of bullets, measure and report that finding. Then take a small sample of cases and prepare them from step one with the reloading dies of your choice and tell us what you are using. Do the process minus powder and primer and load a few dummy rounds. Dusty

[BK7saum]

What die are you using to crimp your cartridges?

Seat a bullet, do not crimp...How tight is the bullet? can it be pushed further inside the case? If so, you need a smaller expander. I barely crimp or dont crimp almost all my cartridges. If I do crimp it is just enough to remove the flare.

If you excessively taper crimp a case you can squeeze the bullet down inside the case. Lead wont spring back, but the brass will, leaving the bullet loose in the case.

[Bazoo]

If you taper crimp so much as to resize the bullet, it wouldn't size the base of the bullet and would still have some case tension.

You mention you have tried RCBS and Lee dies, are you using the lee carbide seat die that sizes the case during the seating operation? That can cause your problem.

[onelight]

What cases are you reloading ?
Are you adjusting your resizing die to touch the shell holder when resizing ?
I think we need more details to give you more than a guess :bigsmyl2: