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'74 sharps
01-18-2012, 08:53 PM
I'm getting a lead ring on my 45lc cartridges at the base of bullet by the mouth of the case. Am belling the case so the bullet sits to the bottom lube groove. I have tried belling the case a little more - didn't seem to make any difference. I'm sure this may have been covered; however, I wasn't able to find any post on it. I am using a beveled base bullet. Many thanks for any help.

williamwaco
01-18-2012, 09:23 PM
That's a tough one.

Try this:

Take a completely resized, deprimed, and belled case.
Place your sizing die into the press to your normal setting then screw it back out 7 full turns of the die. (one half inch ) Seat the bullet - slowly. It should be aproximately 1/2 inch less deep than your normal seating depth.

Does it have the lead ring? My guess is no.
Now screw the die into the press 1/2 turn and reseat the bullet. One half turn = 0.036".
Continue this step until the ring appears.

Now you know where it is happening and that will give you a clue as to what is causing it.

See:
http://www.reloadingtips.com/how_to/crimping_revolvers.htm

for photos on adjusting the seating and crimping die for straight walled revolver cartridges.


Prediction.
Upi are seating the bullet a few thousandths too deep and the crimp ring is forcing the mouth of the case into the front driving band and shaving a "smidgen" of lead.

"Smidgen" is a technical reloading term. 100 smidgens = one gob.

Cadillo
01-18-2012, 09:53 PM
I'll wager that you are seating and crimping in one step. If so, stop that, and it should prevent the problem.

If that's not it, post a picture, which might help.

runfiverun
01-18-2012, 09:59 PM
i'm with cadillo.
your crimp is rolling while you are seating taking off the ring.
you could try a champher tool on the inside of the case mouth also.

nanuk
01-18-2012, 10:23 PM
to stop that ring during the crimp process, could one seat just a bit deeper so the groove is at/past the mouth so there is no lead for it to contact as it turns in?

243winxb
01-18-2012, 10:53 PM
Bullet diameter larger than .452 may be a problem. Another could be the seating die is to small in diameter, removing the bell to soon. Open up the die. Run a sized/belled case into the die, no bullet. Small amount at a time, while measuring the bell.

pastorcurtis
01-18-2012, 11:00 PM
Breaking the seating and crimping into two steps helped this problem for me.

'74 sharps
01-19-2012, 07:30 AM
Thanks for all the help. Checked, and driving band base is about .0013 above case mouth; a great tip about a potential problem area. My eyes are now open to the crimp
issue. I use the RCBS Cowboy dies, and will adjust the seating die to see if that corrects the problem. I do not put a heavy crimp on the case. On my 45-70, I do not crimp at all, and therefore do not have any issues with the lead ring. Will get on it today. Who says being retired is not a full time job.

Cadillo
01-19-2012, 09:29 AM
You will be ahead of the game if you just spring for a dedicated crimp die and seat and crimp in separate steps. There's a reason Dillon sells his pistol die sets with two separate dies for this process.

canyon-ghost
01-19-2012, 09:35 AM
Might also try chamfering the case mouth a little more. I've found that chamfering the outside helps chambering in the gun, chamfering on the inside helps seating. Consequently, I chamfer both sides as part of working brass.

44man
01-19-2012, 10:04 AM
Dies used?
I seat and crimp all of my loads in one step with Hornady dies. Some seat dies remove the taper as you seat, nothing to do with the crimp portion, the deed is done as the boolit and brass enters the die.
You set the boolit into the taper and as soon as the brass enters the die, the taper is removed.
Take a sized, flared case and run it into the seat die short of the crimp portion, take it out and if the flare is gone, buy better dies.
Most dies are made for bullets.

462
01-19-2012, 12:45 PM
"Most dies are made for bullets."

Yep. Quite often, loading boolits requires experimentation and no small amount of un-learning.

geargnasher
01-19-2012, 01:20 PM
to stop that ring during the crimp process, could one seat just a bit deeper so the groove is at/past the mouth so there is no lead for it to contact as it turns in?

Yes, but it works best for cartridges meant to be fed from a tube magazine. Seating and roll-crimping in one step requires careful die/seater stem adjustment and that the cases be trimmed to identical lengths. The issue is that you can roll the mouth of the case just under the top driving band and it will be tight against compression, but not against pull. It's impossible to get the roll tight against the angled part of the crimp groove in one step, so in a revolver the boolits can back out slightly under recoil in the cylinder until they're tight against the crimp. Best to do it in two steps, but I do it in one for my leverguns, or use the Lee factory crimp die.

Gear

ku4hx
01-19-2012, 01:40 PM
I'll wager that you are seating and crimping in one step. If so, stop that, and it should prevent the problem.

+1 I went to seating and crimping in separate operations several decades ago. Haven't had this particular "shaving" problem since.

Roundnoser
01-19-2012, 01:49 PM
I, and others in my neck of the woods call the condition, "lead damming" when refering to that ring of lead shavings that "dams" up around the case mouth.

Anyone else use that term? Just an FYI...

And +1 for the seat / crimp die suggestion. I always crimp with a seperate die.

nanuk
01-19-2012, 03:25 PM
thanks for that explanation Gear, makes a lot of sense to me.