Sizing down when seating

[mattd]

My lee 175g TC cast at .401-.4015, perfect for my purposes. After seating w my lee dies, and pulling the bullet, it measures .3975-3985. Thats after backing out to remove the majority of the crimp. I can remove all the crimp and not down size. But it dosent take much to pop it out w kinetic puller. Is this just what i gotta do? Maybe mess w it for another hour and find a sweet spot?

[williamwaco]

My lee 175g TC cast at .401-.4015, perfect for my purposes. After seating w my lee dies, and pulling the bullet, it measures .3975-3985. Thats after backing out to remove the majority of the crimp. I can remove all the crimp and not down size. But it dosent take much to pop it out w kinetic puller. Is this just what i gotta do? Maybe mess w it for another hour and find a sweet spot?



I am thinking you have too much crimp!
The mouth of the case should appear straight, with at most a tiny taper.
If you can see the crimp pressing into the bullet, it is too much.

[High Lord Gomer]

I had problems loading .38s with Lee dies that seat and crimp in the same die. My problem was different in that it seemed to crimp before it was finished seating and result in the top of the case bulging out enough to not chamber easily. I then bought another crimp die so I could seat in station 3 on the 550 and crimp on 4 the way all of my Dillon dies do.

[Nickle]

Crimping and seating can frequently be done with the same die, BUT, they're best done as separate operations.

I seat first, with the crimp portion backed off, then back off the seater stem, and run the die down to crimp. Sure, it's an extra step. But, one worth doing. Seeing that I usually do pistol ammo in a progressive press anyways, it's seat with a die set to seat @ station 3, and crimp only on station 4.

I get few to no problems.

[mattd]

So while your trying to figure out the right amount of crimp is the process - seat, crimp, pull, measure, repeat till u get something that dosent size down?

[Airman Basic]

So while your trying to figure out the right amount of crimp is the process - seat, crimp, pull, measure, repeat till u get something that dosent size down?

Might want to check this thread:
http://castboolits.gunloads.com/showthread.php?106715

[Nickle]

Lee Factory Crimp Die. They're OK for rifles, but the pistol version is a useless piece of junk, if you ask me.

[blackthorn]

Lee Factory Crimp Die. They're OK for rifles, but the pistol version is a useless piece of junk, if you ask me.

These dies, as are most (if not all) factory dies, are designed to load jacketed bullets. They work wonderfully well for thier intended purpose! With cast---not so much!

[Nickle]

Doesn't matter to me, as I don't, and won't, use them.

[captaint]

mattd - I used to play with those dies in 45ACP - till I got tired of the ritual you're describing. Finally, I got myself a set of Lyman M dies with the separate crimp die. Happiness ensued. Mike

[Rattlesnake Charlie]

The Lee Factory Crimp Die (FCD) for handgun cartridges swages down the case of the loaded round to like minimum dimensions to ensure the round will reliably load in all handguns. Unfortunately, in that process it squeezes down the bullet too. Ditch the FCD if that is what you have. I use the Lee Taper Crimp dies with great success. If you are not using the Lee FCD, it may be you need a larger expander. When using soft bullets, I have had the case reduce the size of my bullet a few thousands. I made custom expanding dies.

[Gohon]

Didn't say exactly what crimp die you are using but if it is the Lee FCD, just knock out the carbide ring in the bottom of the die and you'll have the best of both worlds.

[mattd]

Didn't say exactly what crimp die you are using but if it is the Lee FCD

Not using the FCD, jus the normal seating/crimping die.

Here's another question. Now I'm loading 120g TC 9mm's. the rear driving band gets sized down .003, but the front band stays .357. Is this to be expected with the 9mm tapered case? Am I good with the front staying the right size?

[mdi]

I would go backwards from what you describe; back off the crimp die until the die is not touching the case. Then use the barrel of your gun and move the crimp die down a few thousandths of an inch at a time, until the cartridge chambers easily, and no more. Do not try to crimp semi-auto ammo, just remove the flare from the case mouth, with a crimp die, for reliable chambering. Neck tension should keep the bullet in place...

[williamwaco]

How to seat and crimp in one operation.

It can be done effectively IF you have a bullet with a crimp groove.

You can see an example here:

Note that the example is for a revolver case but the procedure is exactly the same for an auto.

http://reloadingtips.com/how_to/crimping_revolvers.htm

All that said.
It is still better to do it in two operations.


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