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Old November 1, 2012, 08:58 AM   #1
LAH
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Scale

I need to sort by weight several bullets. Could someone suggest a scale with which I could do this quickly? The only scale I own is an old Ohaus 505.
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Old November 1, 2012, 09:08 AM   #2
Mike Irwin
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Well, you've got an excellent tool for the job, but you're not going to do it quickly.

Now might be the time to invest in an electronic powder scale. Decent ones with good resolution aren't that expensive anymore.

If you need to go to a hundredth or thousandth of a grain, instead of a tenth, though, you're probably not going to find a powder scale with that resolution.
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Old November 1, 2012, 09:19 AM   #3
LAH
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Mike a 1/10 grain would work for me.
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Old November 1, 2012, 10:15 AM   #4
Mike Irwin
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Check the Midway site.

They have a Hornady electronic scale for something like $30. That should be more than enough to do what you want to do.
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Old November 1, 2012, 10:32 AM   #5
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You can probably pick one up at Harbor Freight (or some similar store) if there's one near you. I've seen them as low as $20 and they probably go cheaper. It's not a scale I'd count on for working up max loads but it should work fine for sorting bullets.
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Old November 1, 2012, 10:47 AM   #6
m&p45acp10+1
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I agree with the cheapo for weighing bullets. I have one I use for weighing bullets to check drop weight from my cast bullets. I also use it for checking case weight, and water volume. The cheap ones work just fine for that.
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Old November 1, 2012, 11:07 AM   #7
LAH
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Thanks guys. I have some [3000] 30 cal. jacketed stuff I need to run through.
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Old November 1, 2012, 11:52 AM   #8
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I got a Franfurth scale.

Something like $26, comes with a calibration weight and you can zero it.

Hornady was on sale and looks nicer, but its controls interfered with the the way I trickle powder in.

Electronic is the only way to go if you want to sort fast or do quick comparison to see (if you left powder out of a case!)

No dogs to fight for, I think they are all fine, just a matter of backlight and how they layout for what you want to do (controls, how they open up etc)
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Old November 1, 2012, 12:01 PM   #9
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The Gemini 20 is perfect. VERY small (something like 4"x4"x1") and it is fast and accurate enough for powder and bullets (accurate to 0.02gr). no, thats not a typo. I use mine for spot checking my volumetric measure and for the occasional rifle loading I do.

http://www.amazon.com/American-Weigh.../dp/B0012TDNAM
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Old November 1, 2012, 12:26 PM   #10
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tkglazie, does the Gemini scale have an option to read in grains or is it only in grams that must be converted to grains?
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Old November 1, 2012, 12:28 PM   #11
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The Gemini 20 is perfect. VERY small (something like 4"x4"x1") and it is fast and accurate enough for powder and bullets (accurate to 0.02gr). no, thats not a typo. I use mine for spot checking my volumetric measure and for the occasional rifle loading I do

Big Ditto on that one. Only scale i use.
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Old November 1, 2012, 12:42 PM   #12
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Quote:
does the Gemini scale have an option to read in grains or is it only in grams that must be converted to grains?
it switches between the various units with a "mode" button.
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Old November 1, 2012, 01:19 PM   #13
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OK, thanks!
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Old November 1, 2012, 01:34 PM   #14
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There have been some heated debates on this forum and others about the Gemini 20 as an every day powder scale, and I can understand why some would be hesitant to use it for that purpose, but as a bullet/case scale and for backup use it is certainly hard to beat.
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Old November 1, 2012, 05:49 PM   #15
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Just keep in mind that scale is limited to 20 grams capacity (about 308 grains) so you won't be able to weigh heavier .458 bullets, nor finished cartridges in .308 Winchester and up. But if you don't want to do those things, if it is stable and repeatable, it should be just fine.

There are other factors to consider if you want the scale for weighing powder as well as for bullet sorting. Even among electronic scales some reach a stable reading faster than others. Some also have mechanical protection against overload, which is worthwhile where accuracy is wanted, IMHO. Brian Enos says the least expensive scale he sells meets these requirements, but its still a $75 scale, so it's not as inexpensive as some you've had recommended.

But for bullet weight sorting alone, you don't need to spend much. Bullet weight isn't as sensitive an accuracy factor as charge weight. That's because, for a given shape, the ballistic coefficient changes in proportion to weight, going up as the bullet gets heavier. At the same time, that greater weight, for a given powder charge, produces lower muzzle velocity, so there is a degree of self-compensation involved. Additionally, match grade bullets seldom have enough weight variation to matter a whit.

Example, in US Army Standard Meteorological conditions:

175 grain Sierra MatchKing
43.5 grains IMR 4064 in case with 56.4 grains water overflow capacity in a 24" barrel with SAAMI minimum chamber.
Average G7 ballistic coefficient: 0.243 (Litz' measured averge; equal to a G1 BC 0.487).
MV: 2650 fps
Total bullet drop at 1000 yards: 445.6 inches
Adding 5 grains weight without changing outside dimensions (Sierra claims to hold these to 0.3 grains tolerance, but I've never measured a given box of them varying more than about 0.1 grains), that change in weight, using the same powder charge results in:
Average G7 ballistic coefficient: 0.250 (G1 BC 0.501).
MV: 2632 fps
Total bullet drop at 1000 yards: 445.6 inches
(I used QuickLOAD and QuickTarget Unlimited to determine velocities and drops here.)

So, provided the outside bullet shape remains identical and the barrel is perfectly rigid, you're looking at a drop difference at 1000 yards of 0.229 moa for a 5 grain shift in weight. Since the world record 1000 yard 10 shot group is almost twice that (4.2" set in 2006 with a 6.5-284), it doesn't seem to me to indicate that weight alone is a hugely significant factor. Good bullet symmetry that rotates without wobble and flies straight will matter a lot more. It would be far more useful for bullet sorting to have a bullet spinner or some other device that detects eccentricity or asymmetry in the bullets than knowing what their exact weight is.

Note that as you get to less aerodynamic shapes with lower ballistic coefficients, the difference in drop due to weight difference will increase. But less aerodynamic bullets usually are not used at 1000 yards. So the effect at ranges they are realistically used at still isn't likely to matter a lot among commercially produced bullets.

Cast bullets are different. With cast bullets a difference in weight usually indicates a void or an inclusion of dross or other contaminant. These are seldom on the exact axis of the bullet, so they tend to indicate bullets that will wobble in flight and not fly straight. I think the old rule of keeping cast bullets within ±1% of one another (a 1 grain span for every 50 grain of bullet weight) is probably good to stick to for cast bullets.

As to your choice of a scale, I think it's safe to say that for .30 caliber bullet sorting, you probably don't need even 0.1 grains resolution. For that reason, having a cheap scale that maybe doesn't even keep zero better than half a grain repeatability may be just fine. It's only if you weigh powder that you need more precision in the scale.
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