Working up 9 mm load for CZ 85. A few Questions.

[Wobbly]

Novice Lesson Number 634

Whenever you use a digital scale, you must also use check weights. Not just any check weights, but check weights in the weight zone for which you'll be using it. So if your load is somewhere around 4.2gr, then you should be using a check weight certified to be 5.00gr.

The problem for reloaders is that a lot of the scales for sale are simply kitchen scales with a new cover. The check weight supplied is 20 grams. That's 308.6 grains, and no where close to your pistol load. You simply cannot trust that scale. Too much can happen between 5gr and 308gr. The cartoon below demonstrates this...



The scale in this graphic reports a perfect "zero" at 20 grams. Yet it is actually reading 2gr higher at 15gr and 15gr lower at 200gr.

However, you are correct !! A reloader should own 2 scales. And one of them should be a precision beam scale. You'd use the digital for weighing bullets and quick checks. And use the beam for weighing things that REALLY matter.

[Wobbly]

Here is another example that is stuck in my craw. I just recently used the Hornady LnL Auto powder dispenser. After following the instructions implicitly, I am finding that the weighed drop is 0.1 grs. different from the Frankfurt Arsenal digital.

Novice Lesson Number 789

? Were these separate drops ? If so, a powder measure always has some variation in its 'drops'.

You can minimize the powder drop variation by: using the small bore rotor, correct hand technique, installing a powder baffle, not using the first 10 drops, using averaging during setup, etc, etc. However, there will always be some small variation based on the powder measure itself and the powder being dispensed.

You yourself know that very small variations show up on the chrono as very small 4-9fps differences. This is not enough to make you change your shooting style shot-to-shot. In fact you'll encounter greater differences in shooting accuracy by using mixed brass or not controlling your OAL. So 0.1gr change in powder at that point is not the factor making you loose to your buddy. Still we do try to control every step in the process to minimize variations within our control.

? Was this 1 powder drop poured back and forth ? That's a bad idea in itself. Small flakes can get stuck in the containers due to static or simply blown away. Much better to use a small metal washer or BB. By doing that the weight is either there or it isn't.

 

[frgood]

? Was this 1 powder drop poured back and forth ? That's a bad idea in itself. Small flakes can get stuck in the containers due to static or simply blown away. Much better to use a small metal washer or BB. By doing that the weight is either there or it isn't.

 

Yes that is what I was doing. After the dispenser dispensed(?), I poured the drop onto the frankford scale and then into the cartridge. Mind you the dispenser was brand new and I had no faith in it. I did this randomly for the first couple of hundred drops.

The 30-30 loads and the 30-06 loads I was not as picky. But now that you guys mention it, It seemed a lot more stable at the larger drops. It is these teeny-tiny amounts in 9mm. Even my .40 loads have a high level of confidence and consistency sufficient for competition all last year. It seems the smaller the caliber, the more attention is required.

Sadly doing steel challenge and USPSA Production means it will be the highest volume.

I still need time to practice and earn a living. lol

[tdogg]

? Was this 1 powder drop poured back and forth ? That's a bad idea in itself. Small flakes can get stuck in the containers due to static or simply blown away. Much better to use a small metal washer or BB. By doing that the weight is either there or it isn't.

 

Yes that is what I was doing. After the dispenser dispensed(?), I poured the drop onto the frankford scale and then into the cartridge. Mind you the dispenser was brand new and I had no faith in it. I did this randomly for the first couple of hundred drops.

The 30-30 loads and the 30-06 loads I was not as picky. But now that you guys mention it, It seemed a lot more stable at the larger drops. It is these teeny-tiny amounts in 9mm. Even my .40 loads have a high level of confidence and consistency sufficient for competition all last year. It seems the smaller the caliber, the more attention is required.

Sadly doing steel challenge and USPSA Production means it will be the highest volume.

I still need time to practice and earn a living. lol

frgood,

For pistol, I wouldn't use the autocharge for dispensing the powder.  I would purchase a Lee Pro Auto Drum drop and mount it on your Lee expander die.  It has proven rather consistent for me on my turret (with a homemade powder baffle).  Just make sure you wipe it out with a used dryer sheet and run a bit of powder through it to get it powder fouled (lubed with powder dust).  The powder drop is capable of less than +/-.1 gr (I think I could say +/- ~.05 gr) variability.  Consistency is key to getting good drops, how you pull the handle, how fast you are pulling, doing the same thing over and over, etc...

When you load for Powerfactor for USPSA or the like, you need to give yourself a little extra velocity to ensure any variation as part of your reloading process doesn't allow you to fall below the minimum 125 required.  I like to load for a powerfactor of at least 130 for minor and 170 for major (45 ACP is what I use).  This will ensure if you have a slightly light charge on a case during loading and they happen to chrono that cartridge you will still be above the floor.

Adding the drum powder measure to your process will speed up your reloading time (500 rds per week would take me 3-4 hours on the turret but I still do more quality control than most).

Cheers,
Toby

[IDescribe]

As was just mentioned, load for PF 130 or higher for minor.

Also, with the two auto dispensers I have used, the tube from which the powder pours is threaded on the interior to encourage powder to move in one direction as it spins.  This is good for ensuring the powder moves in one direction, but at the lip, the threads grip the powder a bit and it falls in small clumps.  If you take a short piece of a drinking straw and insert it into the tube and tape it in place, the powder will now spill from the straw, which is smooth, and it will spill out in finer clumps, offering a little more precision at the end of the pour.   

[frgood]

Good points to consider. The feedback is very helpful.

Tonights ladder was incredibly accurate. The Hornady dispenser seems to be settling down with each use. Plus, Bullet seating was exactly 1.1480 for every round. Shame heavy rains are predicted.  heh heh

[Wobbly]

Without doing anything else you can run those back though to achieve 1.140". You really don't want to collect data at an OAL you don't intend to use.