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Mongchi
03-22-2009, 08:05 PM
Hello,

I am in need of some help. I am just getting into reloading and have been reading as much as I can and asking questions were I can. I have the Hornady Handbook and have watched the videos on RCBS and a lot on U-Tube. Most of them talk about reloading rifle cartridges. But I wanted to start with my saved pistol brass. I have a Rock Chucker and Carbide Die sets. I understand the cleaning, case prep, priming and charging. What I don't really get is how to expand and crimp.

The Hornady book say to use little or no crimp on the 9 Lugar but doesn’t say anything about the 38. I look at my factory loads and the Win 38 Spec has no crimp the 38+P has some and the Rem 357 Mag looks like it has no crimp.

But here is where I am really confused. The Expander Die, I understand you just want a little so you can seat the bullet. My very first round I didn't use a primer or powder and just a little expansion. When I tried to seat the bullet the brass would not go in the die. So I tried a brass that had not been expanded the bullet felt like it seated great. After a couple of tries I had the length just right. So I made a batch of 50 rounds. I repeated the process with the 9 Lugar and the expanded brass worked fine so I made 50 of them. Just to try I seated a 9 Lugar in a brass that I did not expand and it seated just fine. My question is why did I buy a 3 Die set or do I really need the Expander die?

By the way I really like the Hornady Bullet Puller, I have pulled more bullets than I have finished. I would really appreciate any help or recommendation from anyone because I have about 4,000 pistol rounds to do before I start my rifle rounds, but I still have to buy the dies for that.

Oh, one last thing, whats with the crimp in the middle of my factory loaded Winchester 44 Rem Mag? My Remington UMC ammo dosen't have it?

versifier
03-22-2009, 10:03 PM
Welcom to the forum.

First off, one current manual is not enough to properly evaluate loads. Sometimes there are occasional mistakes in data entry, and even the best proofreaders make an occasional slip. Two is minimum, three is insurance.

With handgun brass, the belling (expander) die needs to be set to open the case mouth just wide enough for the bullet to start into the case without shaving any of the jacket off. Sometimes it isn't really necessary, as with rifle cases, the leverage of the press is enough to do the job, especially if the inside of the mouth has been properly chamfered. Usually though, a slight expansion lets the bullet start much easier. I'm not sure what caused the problem you had, I suspect you weren't expanding enough. Yes, you really need an expander die. My question is why aren't more companies selling 4 die sets when I have to buy the extra dies so often?

Crimping is a separate issue, and the process is quite different between pistol and revolver cases. Most dies sets have crimping shoulders built into the seating dies, which is fine for economy, but is not as easy to work in practice as the manufacturers would like you to believe. You have the most control over the crimping operation when it is performed by a separate die.

Pistol cases are taper crimped. This is a narrowing taper in the die that pushes the expanded mouth straight against the bullet. It is designed to hold the bullet in place during the feeding cycle and prevent telescoping. When a round telescopes, the bullet is pushed down into the case and when the primer is ignited, the resulting pressure in the smaller space can spike the pressure, sometimes with disastrous results. It is the preferred method of crimping because the cases headspace on the mouth and must be stopped by the corresponding ridge in the pistol's chamber.

Revolver cases are crimped in either of two ways, roll or collet. They need to be crimped for two reasons. First, a firm crimp insures more uniform ignition (more consistant performance with the bullets exiting the cases at the same pressure levels to jump the gap, pass the forcing cone, and enter the revolver's barrel. Second, recoil from the revolver can cause the bullets to back out of the cases, causing the cylinder to bind up, and, depending on the revolver's design, can be a real problem to get clear. The heavier the recoil, the heavier the needed crimp. Obviously, a .38spc target load with a minimal charge of Bullseye and a wadcutter will not need the same degree of crimp that a .357mag full charge hunting or self defense load would need. Most seating dies (both rifle and revolver) have a roll crimp shoulder built in. The disadvantage of a roll crimp is that all of the cases must be exactly the same length for it to apply consistently. Changing the degree of crimp also changes the round's OAL as to adjust it, the die is screwed in or out. That means the seating stem has to be readjusted, too. Hence the preference of many experienced loaders for crimping as a separate step. Gaining much popularity in recent years is the collet style crimp (Lee's Factory Crimp Die - FC dies for pistols are taper crimps) which relies on the closing of a collet to push the case neck into a cannelure on the bullet, but even the cannelure is not strictly necessary to use it, making it even more versatile. The lengths of individual cases are much less critical to this kind of die. The pistol and revolver versions also have a carbide sizing ring to insure that the round will easily chamber, too. The rifle dies do not, but they are still the very best way on the market today to crimp those rifle rounds that need it.

I have no idea why cetain .38spec, .357mag, .44spec, and .44mag cases have that impression at the base of the bullet. No explanation I have ever heard has made much sense to me. Such cases process and reload normally though, so I just ignore them.

kg42
03-23-2009, 02:14 AM
Hi Mongchi,

Is it possible that you didn't size your brass in the first place, as you don't mention it?
That would explain why the case couldn't enter die nr3?

About a bullet being seated in a non expanded case, it is possible with JHP/FMJ's and a roundish base (specially if you didn't resize first ;)).

Brass resizing allows your ammo to chamber easily, and the bullet to seat tight in it;
expanding allows all bullets (lead, etc) to be seated easily.

The cannelure at the base of the bullet prevents it from being pushed in when it, for example, hits the feeding ramp in a autoloader.

kg

versifier
03-23-2009, 02:44 AM
The cannelure at the base of the bullet prevents it from being pushed in when it, for example, hits the feeding ramp in a autoloader.

kg

That got me thinking and looking as I didn't remember seeing it on pistol cases, but there in my .45 bucket are a bunch of them. Then I thought: What possible reason could they have for doing it to revolver cases? Maybe lever action rifles. That would make sense. But I have seen it on factory .38spec wadcutter loads, too, the ones with the bullet seated almost flush to the case mouth. I've never heard of anyone loading them in a lever action - I doubt that the bullet would make it out the end of the barrel with some of the lighter target loadings.

kg42
03-23-2009, 05:44 AM
They are many possible reasons...tubular mags, feeding ramps...knocking bad guys down... Someone wrote that when the 45 Colt and others went smokeless, the bullets could no longer seat on the powder and needed the cannelure... As you wrote in an other thread, we don't want bullets to go seat on most powder loads.

About the 38 WC, they had to mean it to make it so deep (not the puny dented one, the deep one).
Some reloading experts recommended that the cases be expanded enough so that the WC bullets could be seated with little effort... almost by hand.... I wondered how tight the factory ones were...

And ammo just looks better with the cannelure, doesn't it....:mrgreen:?

runfiverun
03-23-2009, 07:28 PM
quite often that canellure on the body is where the base of the bullet resides.
also on some of the full wadcutter type factory match rounds the cases are different.
especially the 38. these had a thinner straighter case wall for seating the bullet straighter in line to the bore.

with the lighter 38 specials they aren't going to move under that light recoil ,so the neck tension is sufficent for safety and powder burn.
this is also done to keep damage to cast bullets to a minimum helping insure accuracy.
sometimes your cases will look like there is no crimp but instead of a deep roll there is a slight depression there in the cannellure.
some of my cast loads are done this way as the bullet doesn't have a deep groove but i need a crimp to insure smooth feeding in my lever actions.
your 9mm uses a different type of crimp it is a tapered crimp more like a squeeze [not a roll]
it is used because the case mouth is what stops the case when you are chambering it.
unlike the 38 which uses the rim.[the reason you van fire 38's in a 357]
be carefull when loading the 9mm please... it is easy to overpressure this round.
start low and work up slowly.

Mongchi
03-24-2009, 11:52 PM
Thanks for all the input. As for Kg's question about resizing, the brass was resized before and I had to resize it again before I could use that brass.

On my belling issue, I didn't see any signs of the case shaving any of the jacket off when I didn't use the expander die.

On my 9mm load I am keeping light. I'm using 6 grain of Power Pistol with 115 FMJ.

By the way, if any of you were curious "Mongchi" was a nickname I got in Korea in the Army. It means Hammer.

Thanks,
Steve