Getting single kernel precision cheap!

[INTJ]

You're on the right track, though the 6 BRA has become the dominant LR BR cartridge. It replaced the 6mm Dasher. There are a couple 6.5x47s out there, a few 6.5-284s, 284s, and 300 WSMs, but the 6mm BR and it's derivatives are king.

Just don't kill yourself trying to get a LR BR gun to shoot with a short range BR gun at short range.

 

[BoydAllen]

Are you referring to an RCBS 304 scale?

I am referring to any of the reloading scales that Ohaus made for RCBS, Lyman, and also sold under their own name. I believe that pretty much all of them feature floating agate bearings under their knife edges.

 

[hoz53]

When I got my Sartorius Entris 128 (.001 grains resolution) I tested my RCBS 10-10. I had used the 10-10 for 1K BR several years ago and I wanted to know ho accurate it was. So I loaded up five charges on the 10-10 and made sure the pointers were exactly aligned for each charge. Even with that, there was almost .1 grains of variation across those five charges.

Now a tenth of a grain in a 300 WSM BR rifle isn't significant. I doubt it would matter in a .308. However with my 6 BRA BR rifle it does matter. Using the Sartorius one day I loaded and shot several 5-shot groups that were separated by .1 grain in charge weight, and the velocities consistently increased by a few FPS for each load.

So while an manual scale is better than the RCBS Chargemaster, a manual scale is not close to a good precision scale and a low end electronic scale is worse. I am sure Scott Parker can get a manual scale to be much closer to a precision scale, but it still won't be as fast or as accurate as the AutoThrow/AutoTrickler on a Sartorius.

Then again, outside of LR BR with small capacity cases in good conditions, it likely won't matter.

this is great advice ^^^

 

[BoydAllen]

this is great advice ^^^

I think that we need to make a distinction here. Is this reference to an untuned scale?

 

[hoz53]

I have been on a quest to improve the accuracy of my powder charges. Not quite ready to drop the $$ for the high end system. My steps include:

- I have 2 RCBS Chargemaster 1500 to work with. I would set the throw 0.1 gr light, transfer into my beam scale pan and trickle until the beam balanced. I could see the movement from a single granule of powder. HOWEVER, after the scale balanced, I would lightly touch the pan (up a small amount, then down a small amount) and the scale would not return to the -0 position. For the movement up, it would return short of coming to -0 after it was under the -0 mark. And the reverse for the other movement. I attributed it to the friction of the knife edges. Tried it on two different beam scales, similar result.

Then I watched the Eric Cortina video where he had an alternate method to try to attain improved accuracy from his Chargemaster. He had a scale that would provide accurate measurement to assess his improvement.
https://bulletin.accurateshooter.com/2015/05/cortinas-corner-chargemaster-tips-the-trickle-test/

My trickler "sucked" anyway, so I got the Dandy trickler he was using. Wow what an improvement. No more removing powder granules with tweezers. And since I had two Chargemasters, I throw 0.2 gr. light on the first one and transfer to the second one. First thing I learned is how bad the dispensed charge accuracy is from a Chargemaster. Now is my first scale reading correct, or the second? I am looking for consistency, not absolute. So by slowly adding granules and waiting for the second to read, I feel I have achieved improvement. My ES and SD are less. And I can fill cases at the same speed as I did before using just one scale.

Once your scale balances, I would be interested in you making the beam move the small amount I did, and see if yours balances on -0 again. I would have it move up (or down) enough so the pointer went about 2 graduations above (or below) the -0, but would not come up to the -0 from below. Not 3 swings, just 2.

ive always had a redding power measure but i never could see why i should buy a chargemaster. If im going to trickle up anyway why not just use the power measure i have? Ive never tryed a chargemaster so i dont know and im just asking.

 

[jepp2]

ive always had a redding power measure

I also have a Redding. But I only tend to use it for excellent flowing powders that I'm fine with slight variations in throws. I use the Chargemasters for the bulk of my loading. Normally the +/- 0.15 gr is fine. Why 2? When I'm loading for my annual PD hunt 7K rounds of stick powder.

 

[hoz53]

I think that we need to make a distinction here. Is this reference to an untuned scale?

I also have a Redding. But I only tend to use it for excellent flowing powders that I'm fine with slight variations in throws. I use the Chargemasters for the bulk of my loading. Normally the +/- 0.15 gr is fine. Why 2? When I'm loading for my annual PD hunt 7K rounds of stick powder.

so you think the chargemasters throw more consistent than a redding? especially with stick powders? if im trickling up anyway im not sure it matters but there are times i want to dispense right out of the measure and then it would. Thanks

 

[INTJ]

I think that we need to make a distinction here. Is this reference to an untuned scale?

I did mention that Scott Parker could make a manual scale a lot closer to a Sartorius than an untuned scale. That said, trickling into even a tuned scale would still be slower than AutoThrow/AutoTrickler on a Sartorius or an A&D. If Evan wants to get into LR BR, he is going to have to load a lot of rounds for competition and a speedy powder charge to the kernel helps the whole process.

 

[Hohn]

This is my magnifying glass on my Lyman scale.View attachment 1169503

That is brilliant.

 

[Hohn]

With respect to Cal and his more rigorous statistical approach to answering questions (which i appreciate), I'm talking about going from 0.3MOA down to 0.1MOA for benchrest shooting which is a much different goal than achieving competitive PRS accuracy - the focus of all of his articles.

I am getting maybe 2 in 10 groups that measure 0.3" (at 300 yards, my current development distance where I can resolve bullet holes in all conditions) and the rest are between 0.6" up to 1". I have no data suggesting powder metering is the problem (I don't use a chronograph, and have yet to be convinced that ES or SD have much of any effect on actual accuracy), but charge weights are something that can be measured and eliminated from the variables present. After this, I'll have to dive into the anal retentive art of weighing primers and sorting bullets, because those are the three remaining rocks I've left unturned to date.

Totally valid, I better understand your goal. Best of luck.

 

[bozo699]

I am looking to turn the 0.6" groups at 300yards with my 22BR more consistently into the 0.3" groups I get on occasion.

I don’t think at 300 you will see a difference wi


Part of my routine is I drop a kernel (or pull one out) and ever so lightly bump the pan tray up with my tweezers, enough to swing the scale an 1/8" or so and let it come back to equilibrium. Doing this, it appears to more repeatably return to equilibrium. If you just drop kernels in and nothing else, you might get a couple kernels in the pan before the needle moves on its own.

That is brilliant.

Boyd Allen told me about this trick about ten years ago and it makes a huge difference for sorry eyes for sure.
Wayne

 

[group therapy]

if you have it down to a single kernel, just count the kernels and make them all the same. Something to do during this lockdown.

 

[Steve Ladino]

Yeah, I tried. Can't find the right size straw. So I ordered a set of plastic inserts that are supposed to "fix" The problem.. And yesterday if I swung the plastic cover over it or moved it back the final charge weight changes.. I just don't trust this thing. I now have 50 rounds to tear down. Mine is sitting on a marble slab. Warm it up for at least two hours..

The cm is a very sensitive scale, sensitive to a host of environmental forces such as temperature, kernels of powder and debis that may have fallen into the insides of the area under the pan, slightest breeze's just to mention a few.