Carphunter
Member
- Joined
- Jan 31, 2005
- Messages
- 52
I had been working up some 10mm loads and found I was getting pressure signs at much lower powder charges than seemed right.
I thought I had been overcrimping the cartridges, or had set the crimper in such a way that it was hanging onto the cartridge as the press arm dropped, and stretched the case.
Well, further investigation leads me to believe the problem(s) occurs much earlier in the process.
For info, I'm running a Dillon 550, Redding titanium carbide decapping die, Dillon powder stand / expander-beller, Redding titanium seater, and Redding taper crimp. (I'm not using the Redding expander).
I think at the decapping / sizing die stage, the brass is getting the pulled look.
If you look at the pics below, you'll see that from about where the expansion ring would be, up towards the mouth of the case, the dimensions of the brass are narrowed (kinda like a figure eight, or like pulled taffy). The case then expands where the bullet is inserted
Now, I'm going to start examining my setup, and give Dillon and Redding a call to see if I'm doing something exceptionally wrong...
But, is there a common reason for brass getting like this? Lack of lube on the die or something?
I'm also wondering if the Redding expander in the die set fully opens the case mouth, and bells the rim for bullet insertion.... or if it's only a beller like the dillon funnel. I ask because if I do not crimp, I can not push the bullet into the case with thumb pressure (something I think I used to be able to do)
I've read the Redding setup instructions again...and they're not telling me much.
I thought I had been overcrimping the cartridges, or had set the crimper in such a way that it was hanging onto the cartridge as the press arm dropped, and stretched the case.
Well, further investigation leads me to believe the problem(s) occurs much earlier in the process.
For info, I'm running a Dillon 550, Redding titanium carbide decapping die, Dillon powder stand / expander-beller, Redding titanium seater, and Redding taper crimp. (I'm not using the Redding expander).
I think at the decapping / sizing die stage, the brass is getting the pulled look.
If you look at the pics below, you'll see that from about where the expansion ring would be, up towards the mouth of the case, the dimensions of the brass are narrowed (kinda like a figure eight, or like pulled taffy). The case then expands where the bullet is inserted
Now, I'm going to start examining my setup, and give Dillon and Redding a call to see if I'm doing something exceptionally wrong...
But, is there a common reason for brass getting like this? Lack of lube on the die or something?
I'm also wondering if the Redding expander in the die set fully opens the case mouth, and bells the rim for bullet insertion.... or if it's only a beller like the dillon funnel. I ask because if I do not crimp, I can not push the bullet into the case with thumb pressure (something I think I used to be able to do)
I've read the Redding setup instructions again...and they're not telling me much.