Do I need a factory crimp die?

If my bullet seating die applies a taper crimp of .469 (for 45acp) why do I need a factory crimp die?

No.  Provided they chamber fine, you’re all set.  You should run them through a “chamber checker”.

If you want to spoil your lead bullets by in-case swaging….

bruce martindale wrote:If you want to spoil your lead bullets by in-case swaging….

I have tested this claim and found it to be unfounded.  In my tests the carbide ring of the Lee Factory Crimp Die did not touch the cases of 45 ACP ammo.  When working with ammo that is within specifications it is neither advantageous nor detrimental.

The belief has its origins in the loading of ammo for 45 Colt revolvers that have over-sized chambers and throats.  It was found that by loading larger-than-usual bullets accuracy could be improved.  The Lee FCD does reduce the diameter of these cartridges, ruining the benefit of fitted bullets.

Boxturtle wrote:

bruce martindale wrote:If you want to spoil your lead bullets by in-case swaging….

I have tested this claim and found it to be unfounded.  In my tests the carbide ring of the Lee Factory Crimp Die did not touch the cases of 45 ACP ammo.  When working with ammo that is within specifications it is neither advantageous nor detrimental.

The reason for the controversy is that there is about a .003" manufacturing tolerance in the die as far as diameter of the carbide ring. If you have one that is toward the max diameter it really works well. If yours is toward the minimum size limit, it's going to swage the bullet down in size and cause issues. 

I decided to try an FCD and didn't like it due to swaging. I called Lee and explained the swaging issue I was having. After talking to the rep and explaining it, he agreed to an exchange for a die that was on the max size limit and it's been great. 

YMMV

If your current loading process brings satisfactory results, why try to fix what isn't broken? 

The main benefit to using a separate seating and crimping die (lee or others) is that it simplifies the individual adjustment of seating depth and crimp. This is nice if you have multiple different projectiles to load. For example say 200gr swc and 160gr swc, depending on which variation of each you may want/need a different seating depth. 

As far as the FCD, I have several and they work well in my loading process.

Ever since I started using an RCBS taper crimp die for 45acp I have had no problems with both lead bullets and Jacketed bullets.  I shoot Bayou 185 grain lead bullets over 3.8 grains of Bullseye and a .464-.465 crimp and a crimp of .469 crimp on jacketed bullets and all is well.

troystaten wrote:Ever since I started using an RCBS taper crimp die for 45acp I have had no problems with both lead bullets and Jacketed bullets.  I shoot Bayou 185 grain lead bullets over 3.8 grains of Bullseye and a .464-.465 crimp and a crimp of .469 crimp on jacketed bullets and all is well.

What’s your recoil spring tension at?

I never use a case checker.. I always use the plunk/twist test with my barrel.

Hello Orion my wad gun uses a 9 or 10 pound recoil spring.  I only shoot the light bullseye loads in that pistol  The jacketed bullets I use are in my Springfield armory XD