Another vote for crimping. And another vote for the Lee Factory Crimp Die.
1. In semi-auto pistols, like my .45 acp pistols, you want the bullet to stay put and not get jostled around by flying up the feed ramp. Some bullets are wide enough that the friction fit you get just by seating it is good enough. But other bullets run closer to the shy side of .451" (some jacketed bullets; most cast bullets run closer to .452")
2. Consistent ignition of your powder charge is helped by crimping.
3. My sizing die for .45 acp runs down to within a hair of the shellholder, yet sometimes brass is still slightly larger at the base of brass (nearest the primer pocket, aka the case head) even after the bullet's been seated. The Lee Factory Crimp Die "smoothes" out the whole completed cartridge, right down to the base, so that your cartridges will fit in ANY pistol of that caliber with a SAMMI spec chamber. I learned this by testing finished rounds both in my pistol's barrel (removed from the pistol) and by using a cartridge gauge. By the way, I'm not shooting Glocks and this is not "the Glock bulge" I'm talking about.
Some cast lead bullets for the .45 acp are really almost too fat, in diameter, to be seated in a .45 case, unless you bell the case mouth like crazy. I usually steer clear of these oversized bullets.
Possibly of interest to .45 Colt shooters:
I load for a Ruger Blackhawk also, and the chambers are oversize, like many Rugers. The irony is that the chamber throats, when the gun was new, were UNDER sized, but the chambers are on the large side, although technically within spec. This can cause early case splits, and you won't get nearly the loadings you should get from your cases. Brian Pearce wrote about this recently in Handloader.
For the .45 Colt my remedy for this was to do something suggested by Marshall Stanton at Beartooth Bullets. This guy, like Pearce, is extremely knowledgeable in this area and his website and its Tech Notes are highly recommended.
Anyway, Marshall suggested that rather than buy a seperate neck sizing die, to only size the portion of the case which would snug up against the bullet, why not just back out my sizing die, and just size down about 1/2 an inch on the case ? Well, duh ! That works just great. However ...
If you want that good reliability of the Lee Factory Crimp, then you'll remove the good stuff you did with the neck sizing of the case, unless .... you buy one of Ranch Dog's special order Lee Factory Crimp Dies for the .45 Colt. This special run of these dies crimps like the Lee FCD rifle dies crimp, not like the standard Lee FCD for pistols. Voila !! All problems solved. Now I've got cases that fit snugly in the chambers, so that they don't expand like a bloody bellows when the round is fired, giving me much less working of the brass, and much greater case life. And the crimp is firm, but doesn't touch any other area of the case but the crimp groove, which is all I want.
It took me much longer to type all this than it does to get this setup working. I am a believer, after seeing the results myself. - DixieBoy
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