Check Weight Question

Wolf172

Hello again,
I was loading a pressure series tonight for my 30.06 using IMR 4895 and Nosler Partition 150gr bullets. After zeroing my scale (RCBS 505) I set it to weigh 47 grains. I put check weights in the pan to check the scale (2 twentys a 5 and a 2) and was reading about 1 tenth heavy with the weights . Rechecked my zero and it was dead on so I figured one tenth was no problem. I loaded 5 rounds there and then 5 at 48 grains. Then set the scale to weight 49 grains and with check weights (2 twentys a 5 and two 2's) was 2 tenths heavy. Rechecked the zero and was dead on again so went ahead and loaded there figuring if anything I would be 2 tenths light by not setting it with the check weights. Loaded 5 there and then 5 at 50 grains. Set the scale to 51 grains and checked with the weights (2 twentys, one 10 and a 1) and it was reading dead on at 51. After loading I checked all my weights and everything read right on except the two 2 grain weights. Both weigh 1 tenth heavy. Weighed aggregates and every thing is exact until I put in the 2 grain weights. With both together the weight is 2 tenths off. Was wondering if anyone else has run into this? I am pretty sure the scale is accurate since it weighs all others right on and a combination of all others right on...except with the 2 grain weights. Should I take a smooth needle file and carefully shave a tenth grain off of both of them or not worry about it. It is just kind of frustrating to use the weights and not get an exact reading. I dont know of anyone else that has another scale to check them against or I would do that. Any opinions?

cnsay

If you know they are a tenth heavy, mark them and use them. Never heard of anyone check weighing each time the scale is adjusted. May be a bit overkill unless you are doing serious bench rest target shooting.

dcs shooters

My Lyman 2gr check weights check right on with my Lyman-Ohous scale.
in fact all the ones in the kit check right on.

RCrosby

If it were me, I would 't worry about it. There are too many other variable (temperature, bore condition, bullet differences, etc.) to even think about playing with loads where 1/10 grain difference could get you in trouble.

Tailgunner1954

Like everything else, check weights have a tolerance.
Short of sending your check weights into a NIST (National Institute of Standards Testing) certified lab, you don't really know what they weigh exactly.

1/70,000 of a pound of dirt, paint, extra metal, corrosion, etc on a weight will give you your extra .1gr, just like "polishing" them could take away a tenth grain (or more) of metal from the weight

The primary thing you want when reloading is consistency in your measurements. IE Does 49.0gr today weigh the same as 49.0 did last month, and will it weigh the same thing next month also.

Rocky Raab

Tailgunner wins the seegar.

Unless the scale is off by a grain or more, all you really need to know is how to duplicate good loads and avoid bad ones. So (for example) 49.0 grains on THIS scale, with THESE components and in THIS gun are a good load. You can duplicate that at any time, even if the scale isn't perfectly accurate.

I've come to the conclusion - after a half-century of tests - that a load that varies by ? 1% of the desired charge can NOT normally be detected by the average shooter, whether by velocity or accuracy. The change caused by charge variation is masked by all the other variables involved. Really.

Wolf172

Thanks for the input. I didn't really think that 2 tenth was any big deal at the volume of powder I am loading but the check weights are a new item I recently purchased and was pretty much just checking things out. As small as the weight is it looks like a lot on the pointer when you are trying to get everything you can as consistent as possible when working up a new load...even if it is just a hunting load. I also purchased a Chrony Beta Master and have never used a chronograph before. Took it out on the patio the other day and shot paper wads through it just to get familiar with the buttons and functions. I am sure I will have lots more questions in the future so if you guys get tired of me asking them just let me know. But I figure it is a good thing to be able to ask people who have "been there and done that" for years and get all the advice I can. May save me some time and money in the future and lots of times little tips or obvious things are pointed out that I never even considered or overlook. Thanks again for the input it is greatly appreciated!

idahoducker

quote:Originally posted by Wolf172
I am sure I will have lots more questions in the future so if you guys get tired of me asking them just let me know.

If nobody asked questions here this forum wouldn't exist. We're all here to learn stuff. I'm sure the most advanced reloaders among us have learned something from a new guys "stupid" question so don't hesitate to ask anything.

Rocky Raab

You know what? It works both ways. More than once, somebody new has asked a question I couldn't answer without doing some tests - and I learned something new. I've even gotten an article or two out of it!

jonk

I don't usually even hand weigh charges once I settle on a good one. Variance by +/- .2 gr in any medium to large rifle case doesn't even impact standard deviation much on velocity. Case capacity and bullet weight are going to be off by at least that much anyhow, so hand weighing each powder charge is a waste, unless you sort brass and bullets by weight too.

Now if you do that and are into benchrest shooting, or shooting at extreme range, then yes it matters.

Rather my scale is there to get my powder measure dialed in, then I just dump the charges, check one every 10-20 rounds to verify I'm still good, and go from there.