New to re-loading, couple of questions...

K

Kaponeoh

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Hey guys I started reloading recently and after many tedious hours setting up my Lee Loadmaster I have made some good 9mm pistol rounds but had a few different results when test firing. I am using cci small pistol primers, 5.2 grains of cfe pistol for a campro 124gr RN and a factory crimp. The first 20 or so rounds fired beautifully and left the cases relatively clean but the second run of about 40 cartridges had a few failure to feed and the cases were very dirty on one side, there doesnt appear to be and damage to cases and all the powder is being burnt, maybe my final crimp has loosened up? Not to sure what to do, I am going to try to turn the final crimp down half a turn and try again. Any input is welcome. Oh and I checked length and weighed every single round and fired everything through a glock.

Thanks for any help or suggestions!
 
Soot on the outside of the case is usually an indication of low pressure, because the brass does not properly seal the chamber upon ignition. Your crimp may be insufficient.
 
How did you determine your OAL?

Blackening of the case usually means it isn't creating a full seal, which can happen sometimes on less than hot loads. I wouldn't worry about it too much unless you're not getting consistent powder drops. A sufficient crimp in 9mm is no crimp at all, just iron out the flare. You should be somewhere around .377-.379 at the case mouth.

FYI...

- OAL's listed in manuals/data is completely useless. Always find your own OAL and make sure the rounds plunk and spin.

- How to determine OAL: https://czfirearms.us/index.php?topic=34225.msg189131#msg189131 (If your bullet doesn't easily collapse just use the seating die to shorten the OAL incrementally until it plunks)

Plunk test:

[youtube]AyS9U90IcUc[/youtube]
 
Last edited:
zippy_the_wonder_chimp said:
I've found if I have brass in all 5 stations
of my Loadmaster and am too light on the
ram pressure, bullets may not seat as deep
and/or crimps may not be as consistant.
Click to expand...
This is true. Running 5 shells into 4 or 5 dies creates a fair bit of resistance so if your reloading stroke is not firm the cases incrementally will not go into the dies as far as they would if there was only 1 case and one die. Also, although the Loadmaster turrets are machined to pretty close tolerance they have a very slight amount of upward movement as the cases enter the dies. Varying downstroke pressures will result in inconsistent turret movement which will give you varying sizing and primer and bullet seating depths. As with any press (and even more so with progressives) the goal should be consistent repeatability on the downstroke.

As 4n2t0 said, make sure your OAL is correct for that particular barrel by using the 'plunk' test. Glocks are not too bad but some CZs have relatively short chambers and rounds that are loaded to book specs will frequently not chamber in CZs. And don't overcrimp, especially with plated bullets as too tight a crimp will actually cut through the plating into the lead core which can lead to separation of the plating in the barrel which is bad. BTW a little bit of blackening is nothing to get concerned about as long as your crimp is solid and there is no bullet movement in loaded rounds. It is always a good idea to check OAL periodically with Lee dies. While the o-ring friction system makes for fast seating depth changes it is quite easy to accidentally turn the seating stem in or out.
 
Thanks a lot for the replies, I was checking my OAL against factory specs from a manual so I will do the plunk test and figure out my own. Thanks guys, as always this forum never ceases to amaze me.
Kap
 
Just wanted to add an update and a thank you! Spin testing the new rounds made after successfully seating to desired OAL using the plunk test and the results are perfect, I was way too long, might get to sneak out later to test fire but if not will try again tomorrow. Thanks for everyone's input! There is always so much more to learn that you cant always find in the books!

Kap
 
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