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A grain of truth

Posted: Tue Apr 20, 2010 9:14 am
by boyntonstu
http://findarticles.com/p/articles/mi_m ... _70650314/

Let's compare the two systems of measurement. In the metric system, the base unit of weight is the gram; in the avoirdupois (English) system, it's the pound. The great beauty of the metric system is that it is based on tenths. Want something heavier than a gram? Add some zeros to the right or use the prefix "kilo," and it becomes 1,000 grams or one kilogram. Want something lighter? Just put the zeros on the left with a decimal point, and it gets lighter. The milligram then is 0.001 grams.

You can use scientific notation too. One milligram can also be written as [10.sup.-3]. One of the great drawbacks of the avoirdupois system is that it doesn't have convenient units lighter than ounces, with the obscure exception of the dram, which is still used in shotshells.

With this in mind, all at once the grain begins to show some rational value. They're convenient. We rarely use powder charges under one grain -- and not too many over 100. Bullets run from 25 to 500 grains most of the time. One grain is an easy concept, 64.9 milligrams might not be.

It would seem as if we ended up in the best place after all -- at least from the American shooter's perspective, even if almost everyone else uses the metric system.

FROM THE GUNS BUREAU OF WEIGHTS AND MEASURES:
A comparison of units of weight:
U.S.A. Avoirdupois Metric
1 pound 7,000 grs. 454 grams
1 ounce 43.75 grs. 28.35 grams
1 dram 24.3 grs. 1.58 grams
*** 10 grs. 0.0649 grams
*** 1 gr. 0.0649 grams

Posted: Tue Apr 20, 2010 10:18 am
by POLAND_SPUD
[youtube][/youtube]
@boyntonstu
it seems that your former employer doesn't agree with you :D

@rest
have a look at 1:40.... lol WTF ? did she say it just to make the Americans less ashamed of the fact that the majority of the world has already been using metrics for a long time?

Posted: Tue Apr 20, 2010 10:56 am
by rcman50166
lol well as an engineer I would 100% support the transition to the metric system. The most annoying conversion in the english system if going from pounds mass to pounds force. Have fun trying to remember when to convert :roll:

I believe trying to convert over to the metric system was tried once. It didn't go well because everyone was "afraid" of the conversion. Also, converting every sign in the United States would be quite expensive.

Re: A grain of truth

Posted: Tue Apr 20, 2010 11:09 am
by Ragnarok
boyntonstu wrote:In the metric system the base unit of weight is the gram
No. Since the 1960s, the Système International d'Unités (or, SI units) has been the internationally recognised standard for the metric system, and the base unit of weight is the Newton.

And the base unit of mass is the kilogram, not the gram. It's the only unit in the SI system that has a prefix as part of the base unit.
in the avoirdupois (English) system, it's the pound.
The "English system" is very bad wording. What the US call "the English system" is not used in England.
A ton is a different value depending on where you are. In England, it's 2240 lbs, but in the US, it's 2000 lbs.

Seriously, what you guys use is the "US Customary system" - not the "English system".
With this in mind, all at once the grain begins to show some rational value. They're convenient.
Of the units out there, they probably provide the lowest integer values that represent powder and bullet masses reasonably precisely.

That doesn't mean they're automatically convenient figures however.

Let me demonstrate. I've just invented a new unit of mass called the "Micro-Sandra", so called because it happens to be one millionth of the mass of someone called Sandra.
If I talk about a projectile and say "This has a mass of 377 µSn", it means sod all to you, because you can't visualise what a Micro-Sandra is.

Similarly, grains are useless to someone who isn't familiar with the unit. Yes, it may work well for handloaders, but this is not a forum dedicated to powder-burning firearms, and most people here have never had cause to use the unit.

In the world, enough unit systems have been invented that it's not unlikely that you can find a unit that's more "ideal" for a given purpose than a more common unit. That doesn't mean that people should have to become familiar with the units - as a more versatile system can still do the same job and won't need conversion tables. No, the numbers won't be quite as "neat" - but they'll still do the same job.

A unit like the centigram is easily up to the majority of jobs that grains get used for, and it's much easier for someone familiar with the metric system to visualise.

Posted: Tue Apr 20, 2010 11:23 am
by boyntonstu
Let's all go Metric!

Anyone using psi, 3/4" sprinkler valves, fps, or FPE will get their hands slapped! :roll:

Posted: Tue Apr 20, 2010 11:34 am
by POLAND_SPUD
I sense sarcasm....

it doesn't make any sense to use fps and fpe when you already use grams and meters... well especially given that switching to metrics is unavoidable... it might not happen overnight but it will happen

Posted: Tue Apr 20, 2010 11:49 am
by Ragnarok
boyntonstu wrote:Let's all go Metric!
Brilliant idea. That way you'll be using the same unit system as 95%* of the world. Frankly, I'm surprised it's taken you this long to see the light.

*And no, I'm not joking. The official primary unit system for ~94.7% of the world's population is the metric system. There are only three countries have not officially accepted it - the US, Burma and Liberia.

Posted: Tue Apr 20, 2010 12:02 pm
by boyntonstu
Ragnarok wrote:
boyntonstu wrote:Let's all go Metric!
Brilliant idea. That way you'll be using the same unit system as 95%* of the world. Frankly, I'm surprised it's taken you this long to see the light.

*And no, I'm not joking. The official primary unit system for ~94.7% of the world's population is the metric system. There are only three countries have not officially accepted it - the US, Burma and Liberia.
We are halfway there.

225mm/60% 16" tires.

What is a 3/8" ball valve? 9.525 mm

1/2" or 4/8"? 12.7 mm

When you are used to eights of an inch it becomes second nature.

Perhaps there should be 100 hours in a day and each hour should have 100 minutes.

What animal was terrified of going Metric?

The inch worm.

Posted: Tue Apr 20, 2010 12:13 pm
by boyntonstu
The most important use of the grains measurement is history!

In the days of tangible money, or sound money, or even just plain money, as opposed to "credit," the dollar was easy to define: 412.5 grains of standard ( 90% pure ) silver in coin form. The 412.5 grain figure was an average; the coin weighed 416 when minted. When, through wear and tear, its weight fell below 409 grains, it was no longer a dollar,


Think about it. How can 10 dollars occupy the same volume as a single dollar?

Posted: Tue Apr 20, 2010 12:27 pm
by Technician1002
The US is going metric. Only the die hards are behind the times. Having lived in several countries, I quickly learned to not bother converting if at all possible.

Much of the US has converted due to the large number of imported stuff.

Need to mount your flat screen TV to the wall bracket? Use the recommended Metric Bolts. Work on a car engine? Again most likely Metric. Read the food labels? Vitamins, minerals, etc? Metric. Buy bottled water or soda? Metric again for most of them.

Who cares how many 2 liter pop bottles to a gallon. Don't bother to convert. That is where the difficulty is. Just buy the 2 Liter and serve.

Things like the roads and maps are still in the obsolete format due to government laziness. This should have converted in the 1970's.

The Gas shortage in the late 1970's and the stations trying to use customer confusion to sell gas at higher prices led to a big rejection of selling gas by the Liter.

Gas was cheaper by the gallon and consumers soon figured out the scam. The 33 cent gas was more expensive than the 70 cent gas. They never recovered. Metric gas simply was a rip off and the comparisons stopped and those selling it converted back or died.

With the rejection of gas by the Liter, the mixed standard of moles per Liter or Kilometers per Gallon were never accepted. This was a huge setback to the conversion process that started in the 1970's. Ideally the gas would have gone metric, the roads then follow and we would be measuring fuel economy in Kilometers per Liter or Imperial Gallon like the rest of the world. (Imperial Gallon is 4 Liters for the US citizens that have never stepped out of the country) Our neighbor to the North used to use this quite a bit.

Posted: Tue Apr 20, 2010 1:16 pm
by Gippeto
Imperial gallon is ~4.5 liters. :)

There are many systems of measurement that have been used over time. In this day and age of the internet, conversion is only a matter of GETTING OFF YOUR ARSE and googling for the answer.

Use the units you want, and let the lazy flounder. If they somehow manage to broaden their horizons and learn something new...that cannot be a bad thing.

Metric vs US (English to some) is a pointless discussion IMO.

My (aggravated) .02

Posted: Tue Apr 20, 2010 1:21 pm
by jackssmirkingrevenge
Gippeto wrote:My (aggravated) .02
Surely you mean 0.0148786 EUR :D

I'm a fan of the metric system when it comes to building and calculating, but I must admit when it comes to launchers I find it easier to visualise feet per second and ft/lbs ;) and nothing beats a good pint of lager :D

To each his own, why are we having this argument again?
US (English to some)
... and Imperial to the English, oh how times change...

Posted: Tue Apr 20, 2010 1:58 pm
by boyntonstu
jackssmirkingrevenge wrote:
Gippeto wrote:My (aggravated) .02
Surely you mean 0.0148786 EUR :D

I'm a fan of the metric system when it comes to building and calculating, but I must admit when it comes to launchers I find it easier to visualise feet per second and ft/lbs ;) and nothing beats a good pint of lager :D

To each his own, why are we having this argument again?
US (English to some)
... and Imperial to the English, oh how times change...
If we stay to facts and opinions this discussion may be informative.

How many of you knew that a dollar was a unit of weight?

BTW If you don't like a particular thread, please change channels.

Posted: Tue Apr 20, 2010 2:21 pm
by Ragnarok
jamessskittishrecession wrote:...but I must admit when it comes to launchers I find it easier to visualise feet per second and ft/lbs.
Well, I usually have to convert velocity and energy measurements into Imperial. For comparison with real world firearms, it's less work to convert my own figures than change all the other sets of numbers I come across.

I prefer the metric, but sometimes I'm forced into using the Imperial.

Still, I will admit that I quite liked using the line "0 to 600 mph in 10 milliseconds"* the other day, but it's not as if the metric equivalent is lacking in impressiveness.

*Which roughly relates to a projectile I'm expecting to use in 3vo.
and nothing beats a good pint of lager
Sounds like George Orwell to me. Most Americans probably didn't get that.

To explain for those who've never read 1984, there's a bit where an older gentleman is having a moan about the fact they now only sell beer in litres and half-litres. Apparently a litre is too much, and a half litre too little.

It makes marginal sense in the Imperial system, because a pint is ~568 cc - although it's hard to see why the difference between a half litre and a pint is all that significant.
But with the ~473 cc US pint, it wouldn't make sense at all.
boyntonstu wrote:How many of you knew that a dollar was a unit of weight?
I do live in a country where the currency is called the Pound.

Originally, one troy pound of silver was worth £1. That amount of silver now costs around £130, so I suspect there may have been some inflation.

Posted: Tue Apr 20, 2010 3:10 pm
by boyntonstu
I prefer the metric, but sometimes I'm forced into using the Imperial.

Still, I will admit that I quite liked using the line "0 to 600 mph in 10 milliseconds"* the other day, but it's not as if the metric equivalent is lacking in impressiveness.


"0 to 965.60kilometer/hour in 10 milliseconds"

All kidding aside, beyond the unit definitions, there is another easy path to confusion.

A billion in England is 10^12, in the US it is 10^9.

Did you know that Roman prefixes magnify and Greek prefixes reduce?

A kilogram is 1,000 grams. Roman.

A micro gram is 1/1,000,000 gram. Greek