Powder weight , how accurate does it need to be for rifle

[hounddawg]

I did a seating depth test today on those 80 gn flat base Bergers. Just for grins all charges were thrown on my old RCBS Chargemaster 1500 with no second check or trickling up on the A&D.

shot at 300 yards off a rest and rear bag, cloudy mid 80's very light winds

group 1 - .060 from lands .643 MOA 2.018 height
group 2 - .040 from lands .322 MOA 0.507 height
group 3 - .030 from lands .579 MOA 1.601 height
group 4 - .020 from lands .439 MOA 0.964 height
group 5 - .000 from lands .600 MOA 0.882 height

looks like the RCBS claim of plus or minus .1 grains provides sufficient accuracy for a good load.

 

[mikejonestkd]

Nice shooting!
plus or minus .1 grain is not a major variable for most of us casual shooters.
It reminds me of a story: my majorly OCD brother and I were reloading for his 300 win mag. He was getting frustrated that he could not get the electronic scale to measure any better than .1 grain. I then reminded him that .1 grain out of 76 grains was a trivial amount, and had to do the math for him before he settled down and relaxed a bit.

 

[hounddawg]

Thanks. All the discussion of beam scales and such got me to wondering is I have been overly anal about my powder weight. Last summer I loaded pretty much exclusively on beams and got good groups. I still find them a lot slower to use however. I bought a RCBS 1500 chargemaster about ten years ago and used it for a long time. Somehow it fell out of use and I had not really used it much in the last few years. Seemed to work well enough today

Next test is 15 more using that RCBS and 15 loaded to the kernel by throwing and trickling on the A&D, all at .040 off and shot at 200 or 300

This is just going to be a 100/200/300 load. I have a nice 105 gn recipe for farther out