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pinne65
03-10-2008, 07:03 AM
Up until now I've reloaded and fired a set of 45 Colt cases 3 times. The case length for these vary 3/1000 " at the most. This is Remington brass.

I also have a set of 454 casull cases that I've fired once and never reloaded. These vary 7-9/1000 ". Stupid as I was I didn't meassure them until after I resized. And since I have carbide dies I didn't use any lube, (which I did with my 45 cases). The Casull cartridges were of a brand called HSM. I don't know what kind of brass it is. But they were considerable cheaper than all other manufacturer's.

Would not using lube cause larger variations in case length. Or is it a result of the higher preassure in the casull cartridge. Or lower quality brass. Or something else.

What's your 5C?

Thanks again for any answers!

versifier
03-10-2008, 04:42 PM
You don't need to use any lube with carbide handgun sizer dies. Cases should be measured after sizing, not before (unless you are curious to see how they respond to it). Small length variations in any lot of brass are the reason many loaders trim their brass before they first load it, to square up and equalize everything and to assure a more uniform crimp, especially if using a taper or roll crimp.

I do not know who makes HSM brass, but that is a lot more variation than one normally sees. What you saw in your Rem brass is more the norm.

Using lube did not cause the length variation, it was a result of poor quality control at the factory.

Higher pressures do cause brass to flow more, but this is something we usually observe in rifle cases operating at MUCH higher pressures. Handgun cases don't usually need any more trimming than the initial one to uniform them. (I have several batches of .357mag cases that have been loaded more than 20X and are still less than max length). That doesn't mean you shouldn't check them occasionally, especially if they are fired in a rifle with hotter than normal revolver loads. Occasionally, a cheaply made revolver with oversized chambers (like a wartime Webley or some of the prewar .38S&W top-breaks) will work the brass enough in the sizing operation to require regular trimming, but that isn't something I have ever run into with a modern revolver. I should qualify that by saying that I don't shoot big bore revolvers now, (just Contenders) and I never loaded for one bigger than a .45Colt or a .44mag. It is certainly within the realm of possibility that brass for rounds like the Casull and the other really big thumpers may need periodic trimming, but if so, it is not a problem that I have heard any mention of. There are members here who do shoot them and I'm sure they will let you know.

runfiverun
03-10-2008, 11:48 PM
if your casull die has an inside ball expander it will/can cause
cases to lengthen by squeezing the brass between it and the carbide ring
especially if you are using a colt die for these as 454 brass is thicker than colt brass
i use carbide dies and lube about every 5-6 cases. just me though.

pinne65
03-14-2008, 01:16 AM
I don't think the casull die has a ball expander. They look the same as the 45 dies. Unless of course they both have it. Can't see no ball in there though... Don't know why I didn't use lube on the casull brass. I had read you didn't have to with carbide dies. But the instructions suggested to lube every 5th. There was a clear difference in sizing resistance between lube and no lube though.

runfiverun
03-14-2008, 01:47 AM
ya they say you dont need to i still lube about a third of mine though
they also say to run them dirty through the carbide sizers helps make them
a little slicker ?
your cases probably are stretching on firing a bit then, i've heard guys say their straight wall
cases dont stretch, but i have seen them do it plenty of times
i have seen cases shrink on firing also.

pinne65
03-19-2008, 05:14 AM
Woow,

Cases shrink? What kind of cases were they?

versifier
03-19-2008, 06:56 PM
While it does seem weird, it is not unusual for new straightwall cases, especially .45-70's, to lose a little length on firing as they expand to conform to the chamber. Then, if the resizing die doesn't quite return the brass to factory diameter, they will not be as long as before they were loaded. They don't keep shrinking, though, they stabilize and begin to grow normally after that. If you only shoot mild loads in straightwall cases, especially smaller bore sizes, they may not lengthen at all. I have some lots of .357mag revolver brass that are close to twenty firings and still have not reached max length, and I have others that I load pretty hot for my Contender that I need to keep an eye on. Differences in chambers, brass, and dies also can affect them.