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vsaks

How do you measure the spirits quantity ?

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I was wondering how most of the folks measure the quantity of spirits during the process for reporting to TTB ? We were planning on using level sight gauges in the tanks, but were told that it is better to have the tanks on industrial scales. Would welcome your thoughts on what has worked for you.

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By far the most accurate way to measure is with certified trade scales.

You also need to know the ABV (or proof) then look up density tables to calculate the volume at "standard temperature"

This is very easy when you have containers small enough to lift onto a scale, a bit more complicated for larger vessels.

I am Aussie so not sure if TTB would allow sight gauges. They are very hard to get a sensitive enough reading, and how do you allow for the temperature variation in the tank?

For larger volumes we are allowed to use certified flow meters.

Trade scales are also very useful when diluting and blending.

ps. get yourself a copy of Alcodens , it makes ALL your ethanol calculations so easy

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Which scales are you using ? Are your tanks bolted down for seismic reasons ?

50 minutes ago, Micah Nutt said:

We weigh everything.  

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Fred at Prime Scale will get you hooked up with a nice affordable floor scale, and there are some tanks on wheels for sale here on the forum or hit up St Pats for ones with air gasket lids(variable capacity), certified thermometer and hydrometer, and problem solved. I believe it's the standard, atleast for us little guys. 

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In addition to using barrels on wheels (they can be pretty pricey), I also move my smaller barrels (30 gallons SS - no wheels) around and onto the scale using simple movers dollys that you can get pretty reasonably priced at hardware stores.

Also, another thumbs up for Fred at Prime Scale - would absolutely recommend talking to him first!

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Thanks for the replies, it seems like scales are the way to go. I'll definitely reach out to Fred at Prime Scale.

It seems everyone is moving the tanks around. I was wondering how people with tanks bolted to the ground are using scales ?

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I'll not make a long comment here.  TTB allows sight gauges, but not for any gauge that involves tax determination of bulk spirits.  They want a scale tank in those cases.  Even if you are not tax determining spirits in bulk (most of you will never do that, but I have one client who does), the cut to bottling proof is crucial and I would want to do it with the same equipment TTB wants you to use when tax determining bulk spirits.  Here, for your listening pleasure, are the applicable regs:

Sec. 19.183  Scale tanks.

 

    (a) Except as otherwise provided in paragraph (b) of this section, if the proprietor uses a tank to determine the distilled spirits tax imposed by 26 U.S.C. 5001, the tank must be mounted on scales and the contents of the tank must be determined by weight. The scale tank also must be equipped with a suitable device so that the volume of the contents can be quickly and accurately determined. 

    (b) The requirement to mount tanks on scales does not apply to tanks having a capacity of 55 gallons or less. Such tanks may be moved onto an accurately calibrated scale when a tax determination gauge needs to be made.

Sec. 19.184  Scale tank minimum graduations.

 

    (a) The beams or dials on scale tanks used for tax determination must have minimum graduations not greater than the following:

 

------------------------------------------------------------------------

           Quantity to be weighed                 Minimum graduation

------------------------------------------------------------------------

Not exceeding 2,000 pounds.................  \1/2\ pound

Between 2,000 and 6,000 pounds.............  1 pound

Between 6,000 and 20,000 pounds............  2 pounds

Between 20,000 and 50,000 pounds...........  5 pounds

Over 50,000 pounds.........................  10 pounds

------------------------------------------------------------------------

    (b) For scales having a capacity greater than 2,000 pounds, the minimum quantity which may be entered onto the weighing tank scale for gauging for tax determination will be the greater of:

    (1) 1,000 times the minimum graduation of the scale, or

    (2) 5 percent of the total capacity of the weighing tank scale.

    (c) The weighing of lesser quantities for determination of tax may be authorized by the appropriate TTB officer where the beam of the scale is calibrated in \1/2\ pound or 1 pound graduations and it is found by actual test that the scales are accurate at each graduation.

    (d) Lots of spirits weighing 1,000 pounds or less shall be weighed on scales having \1/2\ pound graduations.

 

Don't ask me to repeat any of that tomorrow morning.  I just know where I have to look.  Take or send the info to a scale company and ask them what they can do for you.  When TTB (then ATF) made gauges of spirits in bulk for tax determinations, we did so in large tanks permanently mounted on a scale, which had to be certified every six months, if i recall correctly.  If you are going to use large tanks, remember that you must have a way to agitate the tank because the alcohol will layer.

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I think your name should be changed to Amazing Dave. Very deep and informative. The part is liked the best is
"I'll not make a long comment here" ;)

So the takeaway is : When withdrawing from bond (for tax purposes) like bottling, you must have an accurate scale per TTB guidelines

For other tanks, you can get away with sight glasses
- low wine receiver : filled from wash still, feeds the spirits still
- feints receiver : filled from spirits still, feeds the next batch of spirits still
- intermediate spirits receiver : filled from spirits still, feeds the spirits receiver
- spirits receiver : filled from intermediate spirits receiver, fills the barrels

25 minutes ago, dhdunbar said:

I'll not make a long comment here.  TTB allows sight gauges, but not for any gauge that involves tax determination of bulk spirits.  They want a scale tank in those cases.  Even if you are not tax determining spirits in bulk (most of you will never do that, but I have one client who does), the cut to bottling proof is crucial and I would want to do it with the same equipment TTB wants you to use when tax determining bulk spirits.  Here, for your listening pleasure, are the applicable regs:

Sec. 19.183  Scale tanks.

 

 

 

    (a) Except as otherwise provided in paragraph (b) of this section, if the proprietor uses a tank to determine the distilled spirits tax imposed by 26 U.S.C. 5001, the tank must be mounted on scales and the contents of the tank must be determined by weight. The scale tank also must be equipped with a suitable device so that the volume of the contents can be quickly and accurately determined. 

 

 

    (b) The requirement to mount tanks on scales does not apply to tanks having a capacity of 55 gallons or less. Such tanks may be moved onto an accurately calibrated scale when a tax determination gauge needs to be made.

 

 

Sec. 19.184  Scale tank minimum graduations.

 

 

 

    (a) The beams or dials on scale tanks used for tax determination must have minimum graduations not greater than the following:

 

 

 

 

------------------------------------------------------------------------

 

           Quantity to be weighed                 Minimum graduation

 

------------------------------------------------------------------------

 

Not exceeding 2,000 pounds.................  \1/2\ pound

 

Between 2,000 and 6,000 pounds.............  1 pound

 

Between 6,000 and 20,000 pounds............  2 pounds

 

Between 20,000 and 50,000 pounds...........  5 pounds

 

Over 50,000 pounds.........................  10 pounds

 

------------------------------------------------------------------------

 

    (b) For scales having a capacity greater than 2,000 pounds, the minimum quantity which may be entered onto the weighing tank scale for gauging for tax determination will be the greater of:

 

 

 

    (1) 1,000 times the minimum graduation of the scale, or

 

    (2) 5 percent of the total capacity of the weighing tank scale.

 

    (c) The weighing of lesser quantities for determination of tax may be authorized by the appropriate TTB officer where the beam of the scale is calibrated in \1/2\ pound or 1 pound graduations and it is found by actual test that the scales are accurate at each graduation.

 

 

    (d) Lots of spirits weighing 1,000 pounds or less shall be weighed on scales having \1/2\ pound graduations.

 

 

 

 

Don't ask me to repeat any of that tomorrow morning.  I just know where I have to look.  Take or send the info to a scale company and ask them what they can do for you.  When TTB (then ATF) made gauges of spirits in bulk for tax determinations, we did so in large tanks permanently mounted on a scale, which had to be certified every six months, if i recall correctly.  If you are going to use large tanks, remember that you must have a way to agitate the tank because the alcohol will layer.

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1 hour ago, dhdunbar said:

 

 

Below are Dave's numbers from TTB and my comments in   bold underlined

           Quantity to be weighed                 Minimum graduation

--------------------------------------------------------------------

Not exceeding 2,000 pounds.................  \1/2\ pound.........sensitivity   1:4,000

Between 2,000 and 6,000 pounds.............  1 pound.........sensitivity    1:2,000    to  1:6,000

Between 6,000 and 20,000 pounds............  2 pounds........sensitivity  1:3,000    to 1:10,000

Between 20,000 and 50,000 pounds...........  5 pounds.........sensitivity 1:4,000    to 1:10,000

Over 50,000 pounds.........................  10 pounds...............sensitivity     1:5,000

    (b) For scales having a capacity greater than 2,000 pounds, the minimum quantity which may be entered onto the weighing tank scale for gauging for tax determination will be the greater of:

    (1) 1,000 times the minimum graduation of the scale, ..........sensitivity  1:1,000

    (d) Lots of spirits weighing 1,000 pounds or less shall be weighed on scales having \1/2\ pound graduations

............... examples for (d) could be 50 pounds  .......sensitivity of 1/2 pound graduation is only 1:100 or at 1,000 pounds 1:2,000

Interesting that TTB allows variation in accuracy between 1:10,000 and 1:100

I think your hydrometers need to be accurate to 0.2 proof or 1:1,000

 

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4 hours ago, vsaks said:

Thanks for the replies, it seems like scales are the way to go. I'll definitely reach out to Fred at Prime Scale.

It seems everyone is moving the tanks around. I was wondering how people with tanks bolted to the ground are using scales ?

Tank bolted to load beam, load beam bolted to floor

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I'll not make a long comment here.  TTB allows sight gauges, but not for any gauge that involves tax determination of bulk spirits.  They want a scale tank in those cases.  Even if you are not tax determining spirits in bulk (most of you will never do that, but I have one client who does), the cut to bottling proof is crucial and I would want to do it with the same equipment TTB wants you to use when tax determining bulk spirits.  Here, for your listening pleasure, are the applicable regs:

Sec. 19.183  Scale tanks.

 

    (a) Except as otherwise provided in paragraph (b) of this section, if the proprietor uses a tank to determine the distilled spirits tax imposed by 26 U.S.C. 5001, the tank must be mounted on scales and the contents of the tank must be determined by weight. The scale tank also must be equipped with a suitable device so that the volume of the contents can be quickly and accurately determined. 

    (b) The requirement to mount tanks on scales does not apply to tanks having a capacity of 55 gallons or less. Such tanks may be moved onto an accurately calibrated scale when a tax determination gauge needs to be made.

Sec. 19.184  Scale tank minimum graduations.

 

    (a) The beams or dials on scale tanks used for tax determination must have minimum graduations not greater than the following:

 

------------------------------------------------------------------------

           Quantity to be weighed                 Minimum graduation

------------------------------------------------------------------------

Not exceeding 2,000 pounds.................  \1/2\ pound

Between 2,000 and 6,000 pounds.............  1 pound

Between 6,000 and 20,000 pounds............  2 pounds

Between 20,000 and 50,000 pounds...........  5 pounds

Over 50,000 pounds.........................  10 pounds

------------------------------------------------------------------------

    (b) For scales having a capacity greater than 2,000 pounds, the minimum quantity which may be entered onto the weighing tank scale for gauging for tax determination will be the greater of:

    (1) 1,000 times the minimum graduation of the scale, or

    (2) 5 percent of the total capacity of the weighing tank scale.

    (c) The weighing of lesser quantities for determination of tax may be authorized by the appropriate TTB officer where the beam of the scale is calibrated in \1/2\ pound or 1 pound graduations and it is found by actual test that the scales are accurate at each graduation.

    (d) Lots of spirits weighing 1,000 pounds or less shall be weighed on scales having \1/2\ pound graduations.

 

Don't ask me to repeat any of that tomorrow morning.  I just know where I have to look.  Take or send the info to a scale company and ask them what they can do for you.  When TTB (then ATF) made gauges of spirits in bulk for tax determinations, we did so in large tanks permanently mounted on a scale, which had to be certified every six months, if i recall correctly.  If you are going to use large tanks, remember that you must have a way to agitate the tank because the alcohol will layer.

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There is quite an easy way to accurately measure the volume of spirit in a container even if it is bolted to the floor.

For example if you have a partially filled tank of say exactly 132.5 proof and you are eventually going to dilute it to say 80 proof.

Firstly estimate the volume it holds (sight glass or dip) say roughly 350 gallons.

Do a calculation to bring this 350 gallons from 132.5 to say 100 proof to make sure you don't overshoot the 80 proof

988.71 pounds of water would be needed if the 350 gallons was exact.

For convenience add 950 pounds (measured on a certified scale) of water, stir very well and allow to settle and cool.

Measure very accurately the proof (best done next day) and it should be around 100.

Say you found it to be 104.6 proof.

Do these calculations.   How much 132.5 do you need to add to 950 pounds of water to bring the water up to 104.6 proof?

The answer is 408.94 gallons at 60 F   is what the container held

That is 427.75 proof gallons

I don't know if TTB would approve, but it is a very accurate measurement.

(I am reasonably confident I have done the calculations correctly but someone might like to check.)

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Let's try to close the loop on the subject of tank issues in general.

When you qualify your plant, you have to list the major equipment, which includes tanks.  You must list “the serial number and capacity of each tank in the plant.”  The regulation goes on, “The list does not need to include any bulk containers having a capacity of less than 101 wine gallons on the plant premises if those containers do not meet the criteria of a tank under Sec. 19.182 (perks, small totes, etc.).”

 Thus, as this is written, a container of over 101 wg capacity should be listed, as should a container of less than 101 wine gallons that meets the criteria of a tank under 19.182.  But 19.182 does not describe what a tank is; it says that if you have a tank, whatever a tank may be, that tank must comply with the general requirements stated in that section.

 

Here is what 19.182 says:

    The proprietor of a distilled spirits plant must ensure that all tanks on the premises used to hold spirits, denatured spirits, or wines are:

    (a) Used for the purpose listed on the application and plant registration;

    (b) Equipped with accurate means for measuring their contents. If the means for measurement is not a permanent fixture on the tank, the proprietor must equip the tank with a fixed device for measuring the contents. However, tanks having a capacity of less than 101 gallons are not required to have permanent gauge devices;

    (c) Accurately calibrated if used for any of the gauges described in this part. Further, if tanks or their gauging devices are moved in any manner subsequent to original calibration, the tanks shall not be used until recalibrated;

    (d) Accessible through walkways, landings, and stairs that permit access to all parts of the tank;

    (e) Equipped or situated so that they may be locked or secured; and

    (f) Constructed to prevent access to the spirits or wines through vents, flame arresters or other safety devices.

This leaves us staring at that wall of large plastic totes in front of us, which is a sight that has become ubiquitous in today’s small DSPs.  Surely, they are containers of more than 101 capacities, and just as surely, they do not conform to the requirements of 19.182.  So … ???

It is a question that has no answer.  When an agency writes regulations that it no longer enforces, someone like me who gives advice is left slowly twisting in the wind.  Therefore, I will leave it to those who have had a visit from TTB to describe whether the TTB employee stared at that stack of totes with the same bewilderment as we do when we visit them through regulation. 

My best answer - I think the horses already have fled that barn through the door TTB has left open.  I Also think it is probably too late for them to try to round them up.  Those walls of totes are here to stay and no one is going to argue with them.  But that is opinion and it should be a humble one at that.

Going on as if TTB were enforcing the requirements, note that the tanks the regulations envision must be “equipped with accurate means for measuring their contents and that, if the means of measurement is not attached to the tank, then you have to go to the trouble of attaching a fixed device.  Are you too staring at those totes again?  

A client points out that in Scotland, where he worked at a distillery, they used a stick to measure tanks and a scale to measure barrels.  It’s been a long time since I engaged in gauging – no, I will not say how long it has been – but back then, TTB, which was then ATF, used to use a stick on occasion tanks as well.   For example, TTB used them to gauge the contents of a railroad tank car – and occasionally on barrels if I recall correctly – and the old gaugers would caution young bucks that you had to make sure that, if the stick was made of wood, you didn’t allow the alcohol to seep up the wood so that the measurement was not accurate. 

Now, stick measurement presupposes that the tank you are gauging has an accurate calibration chart that comes with it from the manufacture, or is furnished by the railroad or trucking line in the case of transportation.  Tank companies post calibration charts for their tanks on line, so they are accessible for some tanks, at least.  Sight glasses make the same presumption, as do float gauges, both of which would qualify as “fixed devises” if TTB were suddenly to give a hoot about the fine points.

Where you locate the tank can affect the accuracy of the gauge (floors can slope), so TTB requires that you get a tank recalibrated when you move it.  When I started consulting, I was conscientious and went out and tried to find someone who said they could do that.  I'll just say, good luck.  You can calibrate it by filling it incrementally and marking the gallons per inch, but is anyone doing that?  If you are concerned about calibration, and given how TTB is enforcing things these days, I think there is no reason, aside from your own purposes, to be concerned, then talk to a large winery and ask them what they do to have their tanks calibrated.

Finally, the regulations say that you must ensure that the tank is used only for the purposes listed on the registration.  Those of you who file applications, as I do, know that the drop down menu you must use to list the equipment, does not allow you to state that you will use a tank for more than one of the three types of operations you can conduct – production, storage, and processing.  The people who create the permits on line application should get their act together.  If a TTB agent challenges your use of a tank for an operation not listed on your registration, and I doubt they would, point out that in the final rule adopting the major changes made to part 19 in 2011, TTB stated:

Recordkeeping accounts. All operations at a DSP are accounted for within four recordkeeping accounts— production, storage, denaturation, and processing. Since the facilities (tanks and rooms) of a DSP may be used for multiple purposes, the accountability for spirits must be maintained of necessity by appropriate records within the four accounts instead of by physical separation.  See:  https://www.gpo.gov/fdsys/pkg/FR-2011-02-16/pdf/2011-1956.pdf

I hope this is an exhaustive treatment of the tank issues that may arise, but I’ve probably missed something.  I do know that I’m tired of talking about tanks at this point and suppose that anyone who has made it this far, is probably tired of reading about them.  It is a beautiful fall day here in the Kittitas Valley and I must have something better to do.

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On 10/8/2016 at 8:21 PM, vsaks said:

Which scales are you using ? Are your tanks bolted down for seismic reasons ?

We use a US Scale FS 4848-5 Platform with a Rice Lake IQ+355-2A Digital Weight Indicator.

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Has anyone has had a visit from the TTB recently and could comment on their treatment of storage tanks and measuring devices?

On 10/12/2016 at 12:00 AM, dhdunbar said:

It is a question that has no answer.  When an agency writes regulations that it no longer enforces, someone like me who gives advice is left slowly twisting in the wind.  Therefore, I will leave it to those who have had a visit from TTB to describe whether the TTB employee stared at that stack of totes with the same bewilderment as we do when we visit them through regulation. 

 

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On 12/14/2017 at 8:44 AM, Dehner Distillery said:

WEIGHT!

Do you need to adjust for temperature when weighing?

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On 10/10/2016 at 6:32 AM, Scrounge said:

Fred at Prime Scale will get you hooked up with a nice affordable floor scale, and there are some tanks on wheels for sale here on the forum or hit up St Pats for ones with air gasket lids(variable capacity), certified thermometer and hydrometer, and problem solved. I believe it's the standard, atleast for us little guys. 

I can second Prime Scales  - I've got a few of them.  Use a calculator - whiskey systems, alcoden, and I assume distillery solutions has them.  No you don't need to check the temperature for the weight, but you will have to temperature adjust (water bath or calculator or the CFR) for an accurate proof content.   Scales need regular calibration and you can be certified yourself.  Apparently it's only a few hundred, which is about what it cost for me to pay someone else to calibrate it. 

Read through the regulations posted.  It's pretty specific.  Also remember to look for explosion proof or intrinsically safe equipment. 

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49 minutes ago, Still_Holler said:

Do you need to adjust for temperature when weighing?

The weight stays the same regardless of the temperature.  Just to be very clear, when gauging with a hydrometer, you always need to adjust for temperature.  But the weight of the distillate being gauged, that's static.

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1 hour ago, Silk City Distillers said:

The weight stays the same regardless of the temperature.  Just to be very clear, when gauging with a hydrometer, you always need to adjust for temperature.  But the weight of the distillate being gauged, that's static.

It seems from a scientific standpoint one wold want to use TTB table 7 and correct the density for temperature when making determinations by weight.

"This table is also prescribed for use in ascertaining the true capacity of containers where the wine gallon contents at 60 degrees Fahrenheit have been determined by weight in accordance with Tables 2, 3, 4, or 5. This is accomplished by dividing the wine gallons at 60 degrees Fahrenheit by the factor shown in the table at the percent of proof and temperature of the spirits. The quotient will be the true capacity of the container.

Example. It is desired to ascertain the volume at 60 degrees Fahrenheit of 1,000 wine gallons of 190 proof spirits at 76 degrees Fahrenheit:

1,000×0.991 equals 991 wine gallons, the corrected gallonage at 60 degrees Fahrenheit."

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Silk City and the others are correct.  The density matters not unless you have high solids (600 milligrams per 100 milliliters.  I'll quote the regulations, which you find in part 30.  I've parsed  into bullet items it to keep the issues separated.  The emphasis is mine.:

§30.41   Bulk spirits.

  • When spirits (including denatured spirits) are to be gauged by weight in bulk quantities, the weight shall be determined by means of weighing tanks, mounted on accurate scales.
  • Before each use, the scales shall be balanced at zero load; thereupon the spirits shall be run into the weighing tank and proofed as prescribed in §30.31.
  • However, if the spirits are to be reduced in proof, the spirits shall be so reduced before final determination of the proof.
  • The scales shall then be brought to a balanced condition and the weight of the spirits determined by reading the beam to the nearest graduation mark.
  • From the weight and the proof thus ascertained, the quantity of the spirits in proof gallons shall be determined by reference to Table 4.
  • However, in the case of spirits which contain solids in excess of 600 milligrams per 100 milliliters, the quantity in proof gallons shall be determined by first ascertaining the wine gallons per pound of the spirits and multiplying the wine gallons per pound by the weight, in pounds, of the spirits being gauged and by the true proof (determined as prescribed in §30.31) and dividing the result by 100. The wine gallons per pound of spirits containing solids in excess of 600 milligrams per 100 milliliters shall be ascertained by [one of two methods I will not quote here].

The instructions for the use of Table 4 are straightforward.

§30.64   Table 4, showing the fractional part of a gallon per pound at each percent and each tenth percent of proof of spirituous liquor.

This table provides a method for use in ascertaining the wine gallon (at 60 degrees Fahrenheit) and/or proof gallon contents of containers of spirits by multiplying the net weight of the spirits by the fractional part of a gallon per pound shown in the table for spirits of the same proof. Fractional gallons beyond the first decimal will be dropped if less than 0.05 or will be added as 0.1 if 0.05 or more.

Example. It is desired to ascertain the wine gallons and proof gallons of a tank of 190 proof spirits weighing 81,000 pounds.

81,000 × 0.14718 = 11,921.58 = 11,921.6 wine gallons.

81,000 × 0.27964 = 22,650.84 = 22,650.8 proof gallons.

The science of the issue is also straight forward.  Heat changes volume, but it does not create mass. Heat does not change the weight, since weight is a measure of gravitational mass.  Gravitational mass is equivalent to inertial mass.  Thus,  you can ignore temperature.  I'll add I'm not a physicist.  I'm just regurgitating what I've read.

 

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@Still_Holler I am a bit confused about what exactly you are asking because in an earlier post you asked whether temperature corrections need to be applied if the quantity of spirit is measured by weight, but then in your example the quantity is given in volume. Let's look at both alternatives, as applied to your example.

If you measure 1000 gallons at 76°F then you would have to use Table 7 to correct the volume to 60°F. As you showed before, the factor is 0.991 and there would be 991 wine gallons at 60°F. For reporting purposes you need the proof gallons and this is simply 991 x 190 / 100 = 1882.9 proof gallons.

If you had weighed the same tank you would have got a weight of 6733 lbs. From Table 4 we get that 190 proof spirit has 0.27964 PG/lb so we can calculate the total proof gallons as 6733 x 0.27964 = 1882.8 PG.

So in summary, if you have the weight and the proof you can go directly to the proof gallons using Table 4.  If you have the volume and the proof then you also need the temperature at which the volume was measured so that you can obtain the volume at 60°F, and then obtain the proof gallons by correcting this volume by the ratio of the actual proof to 100 proof (190/100 in the example).

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TTB requires accuracy of about 1:1000

I deduce that from the requirement that hydrometer need to be accurate to 0.2 proof. 

Meerkat's example of 1,000 gallons; if it is in a cubic container it is approximately a 5 foot cube.  To measure to 1:1000 that is 1 gallon in the container.   Each gallon is 0.06 inches deep. You cannot measure any where near that accuratly with a stick or sight glass. 

A good electronic scale can measure to this accuracy

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