Taper crimp problem

[Johnnn01]

loaded a few 40 s&w dummy rounds with no primer or powder, and cycled manually through my pistol.
one came out with the bullet pushed way into the brass, easy 3/8" deeper. thinking if this was a live round some bad things might have happened.

The rcbs instructions for the taper crimp said .001 to .002 crimp, witch is what I had set the crimp at.

Need some help!!!

 

[OKFC05]

A taper crimp is not what primarily holds the bullet in place in a .40. You have some sizing issues, or undersize bullets. Time to measure cases and bullets...

 

[jwalts27]

A taper crimp is not what primarily holds the bullet in place in a .40. You have some sizing issues, or undersize bullets. Time to measure cases and bullets...

What he said.....You may be belling the case mouth too much. I barely put any crimp on my 40s or any other autoloader rounds I make for that fact.

 

[Johnnn01]

the bullets being used are Nosler 150gr sporting and the brass is being resized with a rcbs carbide die set.

 

[Johnnn01]

will check the belling

 

[jwalts27]

the bullets being used are Nosler 150gr sporting and the brass is being resized with a rcbs carbide die set.

During your charging stage are you belling the case as well in the same step? Check to make sure the die is adjusted right.
On my Lee dies I charge/bell in the same step. If your die is cranked in you will open up he case way too much.

 

[Lou_NC]

Check the actual bullet diameter with a caliper. 150gr is a light bullet for a .40 so you already have less bearing surface between the bullet and case. An undersize bullet may be compounding the tension problem.

 

[Doubless]

Not to beat a dead horse, but the only amount of mouth belling required is enough to allow the projectile to start. It should really be kind of hard to look at the case and even see the amount of bell, if that makes sense. Too much belling will definitely cause problems...

 

[TAROMAN]

Brass that's been fired many times may lose its elasticity, thus the ability to grip the bullet tightly.
I discover this from time to time loading .45 Auto. Setting bullets into charged cases, the bullet will drop in further than it should.

 

[BLUEDOT37]

the bullets being used are Nosler 150gr sporting and the brass is being resized with a rcbs carbide die set.

What OAL" are you loading these to? Have you done the "plunk test" to verify it's correct for your gun?

.

 

[fredj338]

What brass? RP is notoriously thin, only useful IMO for larger dia lead bullets. Other brands may also suffer being too thin. Also check the dia of the expander. You want it 0.001" smaller than bullet dia min. If it is not, polish it down 0.0005", it will help neck tension, which is what holds the bullet in place, not the taper crimp.

 

[Ivan the Butcher]

One of the old school/non scientific methods that worked when I started loading in 1981 or so was: Put a factory round in the shell plate, Adjust crimp die to just touch the case mouth, Set lock nut. If you seat to length in the same step, now is the time to set seating stem length and lock nut in place. Now you are set to factory specs (these can change with different weights or bullet designs. If you need to make adjustments, Remember to loosen the lock nut for that adjustment only and tighten when adjusted. If you add more crimp to shortened the OAL also at the same time. If the threads on the seating stem are 32 to the inch, a 1/8th turn is about .004" depth adjustment. Ivan

 

[scooter123]

If you still have that case that had the extreme setback I would suspect that measuring the diameter of the case would reveal that it was a) not properly sized or B) flared much too deeply.

Since most of us de-cap and size in the same stage you should take a look and see if there is a fired primer still in the case. If there is you missed the sizing stage with this case.

Next is flaring the case too deeply. This is a VERY common mistake for a new reloader to make. Especially if using a flaring die that has a flare pin with a pilot diameter, a flaring ramp, then a larger straight diameter. RCBS dies feature a flaring pin like this and I've seen newbies use the larger diameter of the flaring pin to form an expanded diameter in the case for the full length of the bullet.

The final potential cause is c) an undersized bullet. Unfortunately in order to determine if the bullet is the correct diameter you will need some micrometers that read down to the 1/10,000 inch (or 4 place digital) range because basic calipers are not discriminating enough.

 

[MJFlores]

Try skipping the belling stage all together. I dont bell or flair any pistol cases these days, and dont feel it's even needed unless using lead bullets. Jacketed / plated bullets slip nicely into a sized case mouth with no issue.

 

[ironhead7544]

Try skipping the belling stage all together. I dont bell or flair any pistol cases these days, and dont feel it's even needed unless using lead bullets. Jacketed / plated bullets slip nicely into a sized case mouth with no issue.

True. Make sure the cases have a good inside chamfer. You might have a slightly oversized case expander as previously mentioned.

I use the Lee Factory Crimp die on all my pistol loads. Are you seating and crimping at the same time? Try crimping in a separate step.

You will find that some components will be out of spec.

 

[ChiefStealth]

Try skipping the belling stage all together. I dont bell or flair any pistol cases these days, and dont feel it's even needed unless using lead bullets. Jacketed / plated bullets slip nicely into a sized case mouth with no issue.

I've read this before. I tried this... once. Disaster. Maybe my sizing die brings 'em down a bit more than some others. YMMV

 

[Johnnn01]

I think I had the expander set a bit too deep and the bullets might be running a bit on the small side.
measured up about 20 and came up with: .3994 .3996 .3995
measured up some Hornady xtp and they were all the same at .4002 to
.4003
is a bullet at .3994 junk?
Have not been able to measure the bullets that sunk into the brass,,, as I don't have a bullet puller yet,,,, going to order one tonight.

 

[jwalts27]

I think I had the expander set a bit too deep and the bullets might be running a bit on the small side.
measured up about 20 and came up with: .3994 .3996 .3995
measured up some Hornady xtp and they were all the same at .4002 to
.4003
is a bullet at .3994 junk?
Have not been able to measure the bullets that sunk into the brass,,, as I don't have a bullet puller yet,,,, going to order one tonight.

NO the bullets are fine, I just measured a bunch of 150g Sinterfire frangibles and they all measured .3960 on average and I have never had any seating issues. And I have loaded thousands of those.

 

[fredj338]

Try skipping the belling stage all together. I dont bell or flair any pistol cases these days, and dont feel it's even needed unless using lead bullets. Jacketed / plated bullets slip nicely into a sized case mouth with no issue.

It completely depends on the shape of the bullet base. If they are rounded enough, you can get by w/o flare. If they are squared off, like the XTP, good luck not buckling a case or shaving the bullet base. No, proper case mouth flare makes better handgun ammo. You need just enough to clear the bullet base.

 

[fredj338]

I think I had the expander set a bit too deep and the bullets might be running a bit on the small side.
measured up about 20 and came up with: .3994 .3996 .3995
measured up some Hornady xtp and they were all the same at .4002 to
.4003
is a bullet at .3994 junk?
Have not been able to measure the bullets that sunk into the brass,,, as I don't have a bullet puller yet,,,, going to order one tonight.

If your measurements are correct, while not junk, not to spec either. If buying plated, if you can get them over size, some manuf size like lead bullets, that is almost always better.