[DocAitch]

I was just loading some .44 MAG and was reminded about knowing your equipment and checking the process periodically.
I had worked up some loads with a 200gr RNL bullet with 7.4 gr W231 which seemed to perform satisfactorily. I had used a Redding powder measure which I had acquired for use with extruded rifle powders.(this is a fine piece of equipment and a pleasure to use but it has one foible as I will note)
When I had charged 50 primed cases, they looked fine when I looked at the powder column height while they were sitting in the loading block but I decided to check weigh some random charges before seating the bullets. To my shock the first charges did weigh 7.4 gr but the last weighed as much as 8.4 gr!.
I checked the measure and discovered that the locking bolt on the side of the cylinder was loose and the adjustment nob had apparently crept counter clockwise as I dispensed powder. The change was so gradual that the difference in powder column height was not evident on visual inspection, since any two adjacent charges were very close in size.
I learned a couple of valuable lessons:
1)Weigh at least some random charges before seating bullets
2)Know the foibles of your equipment
3) visual inspection of your charges is good for empty cases or doubles, but can mislead you if you think that you are doing more than that.

BTW, these were for a Ruger RedHawk, so it is unlikely that I would have had a problem other than POI scattering due to charge variations.
DocAitch

[ChaZam]

Good lesson safely learned.

[texnmidwest]

Good lesson and reminder for us all! I also learned recently to double check the load data and not go from memory. 2.3gr and 3.2gr.s are much different charges.....Yep, was loading up some DEWC for my 38sp. Transposed the numbers until I shot a couple cylinders and got to wondering about the stout recoil! I was still below max load but the light target load I was looking for turned out to be a much stouter load. Will be pulling the rest of those for sure....

[chesterwin]

I haven't got my gear set back up yet but I used to weigh the first, last and a middle charge from each block when using a dispenser. (Powder drop)

[Purdy]

That's why I favor the RCBS Lil' Dandy for my pistol loading, no chance for load creep

[Huey Rider]

I also periodically check my wieghts while I'm dispensing powder just to be sure nothing comes out of adjustment. Thanx for the reminder Doc.

[cooker300]

i to was not watching carfully enough one night. and chagred about 25 45colt and a few did not look right weighed a few and was way off. now i check every 5

[runfiverun]

my redding did that occasionally but it would go in one time and out the next.
i put a piece of lead shot under the screw.

[longway]

i admit that i may be a little heavy on my personal caution when reloading,which means im slow i guess.i weigh every charge before going into a case when loading pistol cartridges.i do it for accuracy more than anything else.a few grains can be enough to make differences on that.im also glad this time to admit that paranoia of holding a bomb has influenced weighing every charge. glad folks hear how easy it can happen.good -"heads-up".

[tracer]

Good reminder Doc.I have two redding powder measures,one set up for light charges and one set up for 25 grains and up.The diffrence is the rotor and plunger.I found the big rotor won't throw little charges fer crap.Also when tightening the lock screw it changes the charge quite a bit. Like you said know your equipment

[Jeep Thing]

My Hornady is consistent and I watch a powder cop with each pull stationed just before the seating station.
Less than that much of a change would be obvious.
But ya I check with a scale every so often just to be sure the system is doing a good job.