Odd seating phenomenon?

[Sam1911]

Hi!

I load a lot of .44 Spc. for my 629. (Like 100-200 rds. per week.)

My pet load for IDPA is 6.9 gr. of Trail Boss under a 200 gr. LRN-FP.

I've had the same die set-up since I started with this gun a year and a half ago (well, I only shot this gun regularly about 1/2 that time, off and on).

I use the Lee carbide dies and the Lee FLCD.

Using .431 bullets with the FLRD is a pain in the BUTT. That sizing ring is designed for .429 bullets, I assume, and it grabs every single case on the way out -- HARD. Like some nights I'm lazy and use two hands for the upstroke 'cause I just get tired of fighting with it.

I know you can crimp and seat with the seating die, but I bought the same set-up I'd always used for .45ACP and have been loath to change.

Anyway, last night I got fed up with it, ditched the FLCD, and set the seating die in to give a nice crimp.

But this is the odd part: The seating die works great when backed out so it doesn't crimp at all. I can dial in whatever seating depth I want with the adjustment on top. (The seating ram moves freely, by the way.)

When I turn the die in to crimp the case, the die seats every bullet to exactly the same depth, regardless of the seating stem's adjustment.

Now this isn't that big a deal. It seats them a hair shorter than I might choose to, but it's a rimmed wheelgun case -- who cares?

I'm not sure exactly why it does this but I have a couple of guesses.

The first guess is that, because these bullets have a LARGE, sloped cannelure for taking a strong crimp, when the die squeezes the case closed that taper just pulls the bullet in until the case mouth bottoms out in that cannelure. In effect, the bullets set their own depth.

The second guess is that the crimp ring is grabbing the bullet and dragging it down, somehow. When I inspect the loaded rounds the full-diameter ring just above the case mouth and cannelure on every bullet shows bright fresh metal where something has rubbed it longitudinally.

Obviously the crimp ring is dragging on the bullet there, but whether that is causing the bullet to seat in deeper or the crimp itself does it because of that long, ramped cannelure, I can't figure.

And, worst of all, these rounds work beautifully and I have no reason to complain! Well, except that technically it's not supposed to work that way and I'd intended that the cartridges would come out about 0.01" longer.

Thoughts?

Thanks!

-Sam

 

[NCsmitty]

Have you looked into the seater die to see if you have a buildup of bullet lube causing the problems?

NCsmitty

 

[Sam1911]

Yeah, doesn't seem to be much goo in there. The bullets I use are all factory cast so they're lubed with the hard kind and it's only down in the lube groove. The seating stem shouldn't get too much build up.

But I'll check it again.

Thanks!

-Sam

 

[fguffey]

Sam1911, I do not have a clue, if the bullet seats and finishes with a crimp, I adjusted the die seating depth (over all length) first then adjust the crimp by backing off the bullet seater plug then adjusted the die to crimp, roll or tapper, then screw the seater plug down to contact the seated bullet, then secured the seater plug and die lock ring, after that nothing moves. I seat and crimp at the same time with one exception, I use a full length sizer as a crimp die for one 45 ACP, the rounds loaded in this manner work in the other 45s.

Crimping and seating in one operation, the bullet is moving down while the case is being crimped, this could cause the case to bulge below the crimp and could cause a loss of bullet hold (tension), and also cause feeding problems. The next post will claim this causes 'shaving' of the lead, in the absence of an expanded case mouth, the case will shave the bullet or the bullet will peal the case.



Case bulge and or shaving lead is controlled by the adjustments between seating and crimping the bullet, or the absence of an expanded case mouth.



Remove the seater plug from your seating die, drop a bullet into the die and check to see where it stops, if it stops on the crimp portion of the die, you are seating bullets without the seater plug, or by accident, the plug is adjusted to seat the bullet and crimp at the same time, I would seat a bullet, loosen the seater plug to check it it was contacting the bullet by adjusting the plug down until it contacted the bullet.


F. Guffey