.32 acp headspacing?

[renaissance]

Does the .32 acp headspace on the rim? or on the case mouth?

Cartridge diagrams show the case mouth to be .337
the case base to be .338
and the cartridge rim to be .358.

My problem is this.

Building 32 acps for my colt 1903 Model M, and Beretta M1934
I was using the Lee 3die set...therefore seating and crimping in the same step.
Some (Not most) of my finished cartridges were coming out "Fat" and would not chamber easily or completely.
I reasoned that the answer would be the Lee FCD.
Problem is Lee doesn't make a FCD in 32 acp.
Talking to the Lee people, we decided that I should get the .32 S&W Long (which Lee DOES offer).
I could back out the crrimper (it wouldnt reach the .32acp anyway) and just use the Carbide Resizing ring to iron out my bulge/whatever.
It was even suggested that by inserting a "spacer" between the crimp screw in head and crimper, that I might be able to crimp the acp with the S&W FCD as well.
Well
I got my >32 S&W Long FCD, removed the Crimper portion and tried to "iron out" my "fat cartridges"
It helped but did not completely solve the problem. some would still not chamber completely.
I fashioned a "spacer" out of a pile of washers and got the .32 S&W L to actually crimp the .32 acp.
This seemed to work...but I then realized that the .32 S&W L crimper was a ROLL crimp....and I had always been taught the autos headspaced on the case mouth and should be "taper crimped".
MY fantasy is that the Lee FCD carbide resizing ring is resizing the finished case only to a shade more than .337.
This isn't quite enough for my two .32 acp pieces chambers which are .338 and .337 base and mouth.......and
That the "roll crimp" is taking the edge off the case mouth and allowing the cartridge to chamber completely.
I believe it is working because they are headspacing on the RIM.

Does this seem right to the group?
Is it OK to "roll crimp" my 32 acp

Yes I know that if I was seating the bullets perfectly straight they would not buloge the case...but...couldn't find a "precision guided bullet seater" in .32 acp

 

[Wil Terry]

IT IS A RIMMED CASE. IT IS RIMMED TO HEADSPACE UPON.

I have loaded thousands upon thousands of 32ACP ammunition with and without a roll crimp using one set of RCBS loading dies.

 

[Matt Dillon]

The .32ACP has give me fits to load and chamber in my CZ70. After having loaded ~1300 cases, I believe that I have the issue licked. I too use Lee dies, but do not crimp while seating, but run the rounds separately through a Redding crimp die. This is the only solution that I have found to work for this round in the rather tight CZ chamber. By the way, I'm using the round nose lead bullet from National Bullet company in Ohio. I believe that the round profile of this bullet lends to the issues in chambering. I believe that the S&B .32ACP ammo is what this gun likes most, but my solution works well with those lead round nose bullets. Hope this helps!