Kernel of powder accuracy

H

hounddawg

New member
I was looking for a cost effective way to measure powder down to a kernal of Varget and found these videos. I thought maybe others here might be interested if they are into long range shooting on a retirees budget

https://www.youtube.com/watch?v=HMX4lq90Fy4

https://www.youtube.com/watch?v=slqE3kodO8Y&ytbChannel=null

While a Autotrickler and a high end lab scale would be great https://www.autotrickler.com/auto-trickler.html
$1000 to $1500 is more than I want to spend

you can achieve kernel of Varget accuracy if you have a beam scale and a smartphone for a lot less

Targetmaster also sells a auto trickler for beam scales for about $150 USD plus shipping. At the moment I am using my RCBS Loadmaster to throw .1 low and trickling to weight using my modded 502, not fast but yes I can see the needle move by just adding a single kernel of varget or 4350.

Targetmaster has videos for accurizing most popular beam scales on his Youtube page as well as other shooting related videos

https://www.youtube.com/user/thetargetmaster/videos
 
Seems like a lot of work for hard-to-discern benefits. In general, barrel heating and fouling will alter performance more than an individual grain of powder does, so you've got to let the barrel cool and possibly clean it after every shot to see it. Once you've measured stick powder that closely you also have to be sure every case is charged and then every round handled exactly identically afterward. This is for consistent packing. Stick powders change ignition rates with packing density to some degree. As an example, the late Dan Hackett once wrote that he had worked up a load that worked perfectly when he loaded it at home, but that gave him high-pressure signs like sticky bolt lift when he put the same load together at the bench. He finally traced it to the powder packing due to the vehicular vibration of traveling from his home to the range. This slowed ignition and kept pressure right. The packing issue is why some shooters with some powders have found volumetric metering gets them smaller groups than weighing, at least at some ranges.

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honestly it is not all that much more time consuming than just throwing charges to weight on the Loadmaster. I was really surprised at how inaccurate the Loadmaster was. I just throw .1 low then trickle to exact weight while the Loadmaster is throwing the next charge. Some of the loadmaster charges straight from the pan were very close to 26.7 or even a bit over while others did not move the beam scale's pointer off the low stop

We fine tune ladder tests to see if .1 grains will give us a smaller group but since playing with this new setup I have found that the charges I have been using for these ladder tests may be .1 under or over so really why bother doing ladder tests when that 44.1 grain charge might be 44.0 or 44.2.

140 grain bullet drop with .529 BC at 800 yards

2725 FPS - 191.8 inches
2700 FPS - 196 inches
2675 FPS - 200.3 inches


that's 1 MOA if you have 50 FPS extreme spread of velocity. The X ring on a 800 or 1000 yard F class target is 5 inches, the 10 ring is 10 inches so I try and get my velocity as close as possible. It can make a difference between a 9 or a 10 or a 10 or a X when scoring

That being said for most shooters a 50 FPS difference will most likely not have any effect whatsoever if they are shooting 100 yards or 200 yards.

Anyway this is essentially a freebie for those who own a beam scale and a smart phone and who want to get the most accurate charge possible. Just thought I would share

Oh and I started using a 6 inch drop tube and make sure my ammo stays upright when transported now because you had posted the bit about powder compression a while back. It does make a difference in consistency just as the primer seating tip does. For me every little bit helps
 
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Unclenick said:
Seems like a lot of work for hard-to-discern benefits. In general, barrel heating and fouling will alter performance more than an individual grain of powder does, so you've got to let the barrel cool and possibly clean it after every shot to see it. Once you've measured stick powder that closely you also have to be sure every case is charged and then every round handled exactly identically afterward. This is for consistent packing. Stick powders change ignition rates with packing density to some degree. As an example, the late Dan Hackett once wrote that he had worked up a load that worked perfectly when he loaded it at home, but that gave him high-pressure signs like sticky bolt lift when he put the same load together at the bench. He finally traced it to the powder packing due to the vehicular vibration of traveling from his home to the range. This slowed ignition and kept pressure right. The packing issue is why some shooters with some powders have found volumetric metering gets them smaller groups than weighing, at least at some ranges.

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I've never used a drop tube. Wasn't able to figure out how the drop tube would keep it alright but dropping right into the case wouldn't. Noticed drop tube length makes a difference too. How do you set up a 3' drop tube?

For years my method with coarse powder was to hold the case in the funnel and tap the side of the case with a pencil. It also works every time.
 
Been using a standard RCBS(I think) trickler for eons. A brand spankin' new one's MSRP is $25US. And the $13.99 at Cabela's Hornady trickler will do the same thing.
"...down to a kernel..." Has more to do with how steady your hands are.
"...my ammo stays upright when transported..." Won't make a lick of difference. It's being shaken anyway.
 
I have a Lyman Gen 5 thrower and it is OK. I suggest a different path. Get the A&D FX120i for $500 from Cambridge Environmental. Use your setup to throw light and then trickle up on the FX120i. At a later date you can add the Autotrickler and Autothrow separately. Each of those upgrades will cost $200-$230. You will still be able to trickle with the finest scale I have ever used. The star of the show is the scale. A force restoration scale is a completely different animal from all of the strain gauge scales.

Bill

P.S. During a recent ladder I loaded 10 rounds at 23.5, 23.6, and 23.7 grains average velocity was 2796,2802, and 2806. I don't think a little bit of variation in charge weights seems to have little affect on velocities especially in a node. But OCD is OCD.
 
The 65 guys suggest an electric toothbrush will accomplish the same thing as a drop tube.
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I have been mulling over getting one of these https://www.amazon.com/uxcell-3100RPM-Vibrating-Vibration-Massage/dp/B00AKWRWRW to mount on a board to do a entire box of ammo at a time ever since Unclenick first posted about powder "packing"

For those who do not think .2 grains don't matter that is fine. As long as you are happy with your ammo's accuracy then there is no reason to try and improve it's consistency any farther. You can save yourself a lot of time and money and just use a powder throw like the 100 yard benchrest crowd does. Even a 25 dollar Lee can throw that accurate.

As far as a lab grade scale why would I want to spend 500 dollars when what I have can detect down to the point where it reacts to a single grain of powder? I can use that money toward a new .224 Valkyrie build later this year

edit - BTW a Gempro 250 has .02 grain accuracy for less than 150 dollars if you want electronics. .02 grains is about 1 kernel of varget
 
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Just a quick reply to the Gempro comment. You need to research the difference between magnetic force restoration and strain gauge. My Gempro couldn't hold a zero for 5 or ten minutes. The FX120i held it for 2 days. It held calibration weight for 6 hours with no drift. Trickling 1 kernal of Varget gives an immediate response. The Gempro uses software to minimize drift that negatively affects trickling ability. There is a reason the FX costs 3+ times the cost of the Gempro.

But I am glad your scale lets you see 1 kernal of Varget. You must realize it is only as accurate as your eye and hand when setting it up and weighing.

Bill
 
It does not really matter that much so long as you dont have a terrible powder measure that throws totally eratic. Most bench rest shooters load by volume and dont weigh their charges once their powder measure is set up. I can throw charges straight from the measure and I can weigh charges on the digital down to the powder piece and on paper the groups from the 6PPC are identical.
 
Ok, so 50 fps give a theoretical 1 MOA difference at 800 yards.

How much powder do you need to add to increase 50 fps?

I can tell you it's more that 3 kernels of powder.

You'll likely get that from the cartridge sitting in the hot chamber while aiming.
 
The only reason I made this thread was to let others know there is a viable and cost effective alternative to going out and spending several hundred or a thousand dollars on a lab grade scale if they want more accuracy in their powder charges. For those who have the money to spend on a lab grade electronics I say go for it. I would rather spend that money on practice rounds and replacement barrels as long as I am getting the same accuracy from my old 502 beam scale. Once past the learning curve it I can trickle to final weight almost as fast as the Loadmaster can throw the initial charge on .223. I will load some .260's this afternoon and will wager I can keep up with the Loadmaster with the larger charges
 
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One of my favorite cartoons from Precision Shooting magazine, was of a guy on his garage roof with an 8# can of powder, long drop tube, pouring it into a cartridge case on the ground.

A quick and easy way to settle powder charges, is to fire up your vibratory tumbler, then hold the tray of rounds down on it for a few seconds.:)
 
Don Fischer,

I used the drop tube because it was an easy quantitative comparison of effect. The only way to do that with tapping or a vibrator of some kind is to attach an accelerometer and see what the vibration level is, then time how long I keep it vibrating, based on the expectation the longer I vibrate the more the powder will settle. I figured nobody on the board could conveniently replicate that, so the traditional drop tube won out.

The way I set up the long drop tube was with a piece of hard plastic tubing I could chamfer for contact with the case mouth. Mine was an old piece of Barex tubing I'd had left over from work years ago, but you can go to any plastics retailer and get polycarbonate or PVC tubing. Just buy it with the bore is a little smaller than the case mouth so the powder drops straight through without hitting speed bumps.

I have an old ring stand like chemists use. I used a flask clamp (the kind with closing fingers) to hold the tube, and I adjusted it with a post level until it was straight up and down. That, btw, may not be necessary, as a number of folks have reported good packing from powder coming down a tube at an angle so the powder swirls into the case. But I was out for maximum velocity of fall.

I taped a small powder funnel to the top of the tube, held the cases up against the bottom of it and poured from a weighing pan into the funnel. Voila!

Now, how does that compare to what you can get out of a vibrator? I don't know. A vibrator packs by tossing the powder around enough that its grains get opportunities to reorganize to a lower potential energy (lower average height) position. But if it vibrates too violently, it can make the ones at the surface hop around and never settle and can give opportunities to randomly stack up to higher potential energy positions and knock them down again. In other words, you can inject too much energy to achieve minimum energy states. So, I suspect you need to find an optimum degree of vibration and an optimum length of exposure to it, and then gradually turn the vibration down to get maximum settling. I'll have to try that. But there's no guarantee transportation couldn't loosen it back up again some.

It seems to me someone talked about driving his charged cases around in his truck for a couple of weeks and then checking the settling. maybe that's the way to go.
 
You can get +/- a kernel of powder accuracy for a lot less than $1000 (like less than $50 if you already have a beam scale).

A beam scale, trickler, gear motor, photo switch and a relay.

https://www.youtube.com/watch?v=nA0_KDjbBGQ

Not very complicated to put together.

https://www.youtube.com/watch?v=UxPenA7c0hE
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Targetmaster in the UK will sell you a powered trickler and optic cut off all put together for about 160 + shipping. Fits pretty much any common beam scale. There is info on his website

Honestly though with the phone camera hack and throwing the initial charge on the Loadmaster I am quite content to top off manually. The camera + the extended pointer hack made beam scale loading tolerable again. Not as fast as just using the Loadmaster however. A range trip or two and some chrony data recorded will determine if it is worth the bother to continue
 
I was looking for a cost effective way to measure powder down to a kernal of Varget
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This level of powder accuracy will make virtually zero measurable difference in your quality of ammunition. Rod
 
This level of powder accuracy will make virtually zero measurable difference in your quality of ammunition. Rod
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edit - from what I have learned in the past few days is that my trusty RCBS Chargenaster 1500 has a extreme spread on charges of over two grains. One kernal might not make a difference but two grains most certainly will at mid and long range.

I have shot appx 1000 rounds across a chrono in the last six months at 600 and 800 and one thing I know for sure, vertical dispersion is directly linked to velocity variation. The lower the ES and SD the fewer "flyers" that end up in the 8 ring and 9 rings above or below the 10 ring. That is just common sense and can be verified by any ballistics calculator. Will 1 kernal make much difference? Maybe maybe not but then I sort cases by volume, turn and ream necks, anneal after every firing so why not bother spending another 15 seconds per round to get my charge as close as possible. The mods I made on a scale that was just gathering dust on the cost me nothing but time, why not use it?

in F class 1 less nine and one more ten or 1 more X can make the difference between winning and second place. Now if learning how to read wind and the mirage were so easy as precision reloading we would all be high masters
 
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