Author Topic: Why can I bleed jacket/core several times? (Read 1124 times)

jcunclejoe · « **on:** July 12, 2005, 10:15:30 AM »

I'm using a Corbin CSP-2 (pre-2002) swaging press with a set of CH handgun swage dies. I had a 1" ram extension made to allow the press to be used with the short swaging stroke. I can put the lead in the cup, add a little lube to the outside of the jacket and core and bleed/seat the core/jacket. Then I can put it back in the die and bleed more lead off, and then I can bleed it again. My core jacket weight is 3gr over target weight before bleeding.

It seems to me like it should bleed once and then be done.
Any suggestions?

Thanks
Joe

Rick Teal · « **Reply #1 on:** July 12, 2005, 01:03:47 PM »

I believe that this is because of "spring back". The jacket expands with the swaging process, but tends to spring back a bit toward its original diameter. This causes the lead to rise a bit in the jacket.

If I recall correctly, Dave Corbin deals with this in one of his books. When swaging cores he mentions tapping the handle three times to fix the core weight. Since there's no jacket involved at this point, it may be the die itself that's expanding and springing back. When I make cores, I hold the handle down a second or so in case more lead wants to seep out of the core.

jcunclejoe · « **Reply #2 on:** July 13, 2005, 07:51:31 AM »

I think you may be right there. I may need to have a core die made, then plug the bleed hole and use the die I have for core seating only.
I'm making 41's from 10mm jackets so there is probably quite a bit of springback trying to take place.
Separating the steps might fix the problem.
Thanks
Joe

talon · « **Reply #3 on:** July 19, 2005, 01:43:09 PM »

jc, If you aren't annealing those shell casings, do so. That will take most of the springiness out of them. You can do that with a hand propane torch if you want. First, make sure that the primer, dead or not, is removed. Then heat the casing in a dark room to a dull cherry red. Let cool, and the lub and proceed as you have been, but as Rick says, be consistent in your swage stroke.

jcunclejoe · « **Reply #4 on:** July 20, 2005, 09:58:43 AM »

Thanks for the tips Talon. I'm trying to make 41's with 10mm jackets. I suppose I could anneal some jackets/cups but there are no primers involved in my swaging process.

I'm having a separate lead die made to set the core weight before I seat the core and bump it up to size. I think this will solve the problem.
Thanks for the help.
Joe

talon · « **Reply #5 on:** July 20, 2005, 12:44:49 PM »

jc, Somehow what's left of my brain thought you were using shell casings rather than jackets (which you plainly stated as 'jackets'). My mistake. But, annealing some lots of jackets is necessary, and easy to do if you have a hand torch. this is especially true if the jacket isn't exactly the right size for the die (1 or 2 thousandths smaller in diameter). Other than what has been said already, the only other thing I can think of is that that really little hole at the top of the nose in the CH die does require you to hold the press handle at the bottom of the stroke for a second or two. Lead takes time to pass through a hole: the greater the difference between the supply side of the hole and the hole itself, the longer you have to wait for all of it to pass thru at any given pressure. While I've read that lead is a 'dead' metal ( ie, no springback), I don't think that is really an accurate statement. What Rick said is true: you have to wait at the end of the power stroke until lead stops moving. Getting and using a core die won't eliminate this 'wait' in the jacket-core swage cycle, but it will certainly make the wait shorter and the 'feel' of the power stroke much more consistent.

jcunclejoe · « **Reply #6 on:** July 21, 2005, 06:56:36 AM »

Thanks again talon, when I got the CH set the bleed hole in the punch was about .015 in diameter and I had to stick a small sewing needle through it to even be able to see light. I drilled it out to .031 then I got a dremmel, diamond tapered bit that runs from .045 to about .065 over 1/2 inch. I ran that into the bleed punch from the bottom side until I had removed all of the parallel in the bleed hole and started to enlarge the top side. Then I polished the bleed hole and the semi-spherical face of the punch to a nice finish. The lead now flows very easily. I have left the handle down for up to a minute. Even then I can trim the bleed, put the jacket/core back into the die and bleed it again.
I have not measured the diameter of the bleed to see exactly what diameter my bleed hole is but I think it is right around .050 to .055
I just don't want to go too large or I will lose my fill out. I'll measure the bleed diameter and get back to you.
I'm sure it will help to have a separate core form die and to close the core seat die system. We'll see.
Thanks again.
Joe