Continuing on with LlindeX's great idea and on the heals of a spotty outing I had earlier today, here is some aspects to the
TightNeck case preparation he thought of.
I did not have a .45 Long Colt dies set, but I did have a .45 ACP one, so I figured I'd fiddle around with it. As Llindex observed, due to shorter pistol caliber dies versus the long 450B brass, there is a challenge getting the same amount of case shouldered down with each one processed. That is due to the fact that you can not screw the pistol dies out far enough so that you achieve the length of shouldering at the top of the ram stroke with the 450B case. Easy fix. Get a longer decapping stem from some other Lee rifle caliber die set and adjust it to limit how far up the case travels into the shouldering die before it stops. Of course, I didn't have a Lee die for a longer rifle caliber, so I just used a similar diameter piece of rod stock I had in one of the junk boxes. I just adjusted the insertion depth of the case to shoulder it the distance that in this case, the Barnes 275gr XPB bullet seats, ran the rod down until it hit the top of the case web inside and locked it down to serve as a limiter.
For my set of 450B dies, they resize brass to an OD of .474 at the mouth. Seating a bullet stretches the mouth a little and I usually then follow up with a pass through the Taper Crimp to take it back down near .476. In the following image I have a normally resized piece of brass next to one ran through my .45 ACP to the depth of the 275 XPB bullet. The .45 ACP die shoulders the brass down to .468 OD and you can see it as well as feel it when you slide your fingers over it.
The resulting case mouth OD with the 275 XPB seated was a beautiful .476
This yielded a stronger and more consistent seating resistance than just seating into the normally resized case.
As for my concern of whether the case would stretch around the bullet as it seated, or whether the bullet, being made of a softer metal would squeeze down as it got seated was abated when I pulled the bullet and measured it. This particular one started out at .45130 at it's widest point and after pulling it from the
TightNeck case, it was .45115 at the widest point. So NBD. An important note: With a softer cup and core style bullet, this may not automatically be the case and you'll have to try one and remeasure it to make sure. My gut feeling is aside from the plated style jackets, which are not necessarily a good idea in this caliber anyway, it'll be ok. Working the case mouth brass and additional .008 inches repeatedly may require drawing or annealing it every now and then to keep it from work hardening, depending upon how many times you reload your 450B brass before it gets too deteriorated.
I have briefly mentioned this in Part 2 of my thread "More Barnes 275 XPB"
Here.
Your thoughts?
Hoot