Why and when to use Grain as a unit of weight measurement

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POLAND_SPUD
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Tue Apr 13, 2010 1:10 am

uhmmm let me post what I was about to post in your previous thread before it got locked....
However, was there ever a bullet that was manufactured that weighed 12 grams
oh damn... I hope it's a joke, not your real argument ? well in case you are not aware of this... your 12gr bullet weight is more like:
12.05gr, 12.0002498gr or 12.03723952gr (which is closer to 0.78g :D )

....but for simplicity sake it is rounded to 12gr because it was measured and written down in a country that uses imperial units...

damn you really have lame arguments...

Indeed, if you are making air guns, it is nice to compare your results with the "real" world
well in case you haven't noticed... your 'real' world uses an archaic measurement system...
so yeah if you want to you can even post here using hieroglyphs or Indus script :wink:
The grain is used to measure the mass of bullets, gunpowder, and smokeless powder; it is the measure used by the balances used in handloading; bullets are measured in increments of one grain, gunpowder in increments of 0.1 grains.[3] Moreover, the grain is used to weigh fencing equipment, including the foil. In archery, the grain is used to weigh arrows and arrow parts
check some sources outside of the USA and UK. No one uses grains any more.

In fact I guess that most of gun manufacturers, engineers, basically anyone who has to calculate stuff, etc. would like to switch to grams and metric units becasue they are more convenient... but they can't do so becasue there are lots of hillbilies (metaphorically speaking) who don't know how to use them... not becasue grains are better
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Tue Apr 13, 2010 1:33 am

only time to use grains on a spud gun forum is when you want to act smarter than someone else.

EDIT: "Watch me impress you with my knowledge of rare and exotic measurement systems"
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Ragnarok
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Tue Apr 13, 2010 7:49 am

boyntonstu wrote:Another nice thing is that when I add a little hot glue to a dart, I can see that I added 4 grains.

It is easy to remember. Much easier than a gain of 0.259 grams.
I'd say "That's a quarter gram, dammit" - or if I had to be more accurate, 0.26 grams. But I doubt that that 0.01 grams would matter. The difference that will cause is utterly insignificant compared to other factors affecting muzzle velocity.

Grains are a stuffy Imperial unit that no longer needs to exist, and which a huge majority of people are not automatically familiar with.
If I say 463 grains... most people on this forum can't visualise what 463 grains means. Even I have to mentally convert it to know what it means. But if I say 30 grams or "a bit more than an ounce", then the job of visualising it is suddenly much easier.
In fact, the grain is the only unit of mass measure common to the traditional three English mass and weight systems (avoirdupois, Apothecaries', troy).
Whoopdedoo.
Every single metric unit is free of ambiguity. The fact that grains are free of it is not something to be proud of - lack of ambiguity should be inherent in any measurement system!
When you list the weight in ounces, or grams, will you also include grains?
No. Just like I'm not going to include long tons, slugs or solar masses.

I provide conversions when a significant proportion of the forum's members will need that conversion in order to visualise what the number actually means.

Not only do very few people on this forum actually use grains, but very few of those people are not also familiar enough with either grams or ounces for those measurements to be of use to them.
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boyntonstu
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Tue Apr 13, 2010 8:20 am

If I say 463 grains... most people on this forum can't visualise what 463 grains means.

7 NATO bullets is what I visualize.

When thinking about guns and projectiles, I like to compare where I am in comparison to a .22 bullet which weighs about 30 grains.

Therefore 463 grains is about 15 .22's

I can relate my projectile weights to bullet weights.

I find it a reasonable comparison.

Getting back to air rifles, imagine using grams or ounces for .177 or .22 bb's or pellets.


For example:

A Gammo X10 .177 target pellet weighs 7.7 grains.

A Gammo X10 .177 hunting pellet weighs 7.6 grains.

or

A Gammo X10 .177 target pellet weighs 0.498 951 grams.

A Gammo X10 .177 hunting pellet weighs 0.492 471 grams.


Using ounces makes it worse.

That is exactly the reason why grains are used for bb's and pellets.

(Find us anyone who sells bb's or pellets using grams or ounces)
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POLAND_SPUD
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Tue Apr 13, 2010 9:08 am

A Gammo X10 .177 target pellet weighs 7.7 grains.

A Gammo X10 .177 hunting pellet weighs 7.6 grains.

or

A Gammo X10 .177 target pellet weighs 0.498 951 grams.

A Gammo X10 .177 hunting pellet weighs 0.492 471 grams.

That is exactly the reason why grains are used for bb's and pellets.

(Find us anyone who sells bb's or pellets using grams or ounces)
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no offence but... What I don't know is whether you a troll or an idiot?

I PMed you once then I posted here... then rag has explained this too... how is it possible that you don't get it ??

(Find us anyone who sells bb's or pellets using grams or ounces)
Duuhh....
in case you don't know it - pellets and ammo in Europe (not UK) is measured in grams..
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boyntonstu
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Tue Apr 13, 2010 9:28 am

in case you don't know it - pellets and ammo in Europe (no UK) is measured in grams..

This is an American Forum, last time I checked.

We drive on the right.

We buy all our pellets, bb's, bullets, arrows, etc. in grains.


Although I prefer the Metric system, we buy our machine screws using the English measurement, gasoline by the gallon, weight in pounds, clothe by the yard, and concrete in cubic yards.

Curiously, tires use mixed measurements.

A 225/60 16 tire has a tread width of 225 mm a sidewall height of 60% of 225 and the tire fits a 16" rims.

Try buying ammunition using grams in the U.S. and you will not be successful.

Let's agree to share knowledge. PERIOD!!!


We can all learn from each other.
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Ragnarok
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Tue Apr 13, 2010 9:31 am

boyntonstu wrote:Therefore 463 grains is about 15 .22's
<sarcasm>Well, that's easier than saying 30 grams.</sarcasm>
Getting back to air rifles, imagine using grams or ounces for .177 or .22 bb's or pellets.
I don't need to. I do weigh and group my air rifle pellets in grams.

And as I've weighed literally hundreds of the things, I know how much their weights can vary. And they are NOT precise to tenths of a grain. Even the "premium" varieties can vary by half a grain.

I've got nominally 7.9 grain pellets (0.51 grams). Seen them at everything from 0.05g (0.8 grains) either way. But, the mean weight is actually 0.52 grams (8.0 grains).

Your 7.7 and 7.6 grain pellets, if you just call them 0.50g and 0.49g, then that's far more precise than the pellets themselves are.

Now... time for me to talk maths.

What you're doing is very very poor mathematical form. You're taking numbers which have been rounded, then put mathematical precision on them.

It's like the joke about the museum guard:
Visitor: "Excuse me Mr Guard, how old is this dinosaur?"
Guard: "80 million years and 4 weeks."
Visitor: "How do you know that?"
Guard: "Well, when I got the job 4 weeks ago, they told me it was 80 million years old."


After any calculation, you should NOT give your answers precise to more significant figures than your initial inputs. Your answers should have been 0.50g and 0.49g (both to two significant figures, like the grain weights) in the first place.

If those pellets had been sold as 7.70g pellets or 7.60g pellets, then 0.499g and 0.492g would have been acceptable answers, as they all have 3 significant figures.

To convert 7.7 grains (2 significant figures) as 0.498951 grams (6 significant figures) is a WRONG answer. Try that on any maths exam that actually meant something (i.e. counting towards any meaningful qualification), and you'd get it marked as wrong (and if you didn't, it should have been). The right answer is 0.50g, given to 2 significant figures.

You are not allowed to use "grams have more significant figure" as your argument, because IT IS MATHEMATICALLY WRONG TO CONVERT THEM WITH MORE SIGNIFICANT FIGURES.

It's a basic mathematical rule. Learn it.
Find us anyone who sells bb's or pellets using grams or ounces.
Well, if you're going to deliberately load the question by limiting it to a country which uses a backwards measurement system, then of course it's going to be hard.

But here's one for you. Find me one properly qualified high school maths teacher who would tell you that you're using significant figures properly.
Last edited by Ragnarok on Tue Apr 13, 2010 9:41 am, edited 1 time in total.
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boyntonstu
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Tue Apr 13, 2010 9:40 am

But here's one for you. Find me one properly qualified high school maths teacher who would tell you that you're using significant figures properly.

Find me one properly qualified high school English teacher who would grade your sentence an A.
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Tue Apr 13, 2010 9:50 am

in case you don't know it the only reason why you haven't switched to metics yet is becasue it takes time... not becasue it's the best measurement system that exist... by insisting on using grains, which most people from your country can't use anyway, you make it harder for your country to develop


yeah I guess we can all learn a lot.... you can learn from us how to use kilos and we can teach you how to use metres :D

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Tue Apr 13, 2010 10:48 am

Rag, you talking about avoiding nonsensical precision reminds me very much of dimensioning a drawing. I have seen people add a dimension to a drawing where the main value is in 2 decimal places, but they then add a 3 place tolerance to it, and a very specific tolerance sometimes. Its strange, because if the main value is so damn important to add a precise, specific tolerance to it then the main value should be 3 decimal places as well. Anyway, I have to deal with making judgements about precision and what is appropriate a lot and reading your post was like reading the mind of a designer...oh wait, you are a designer. lol.
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Ragnarok
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Tue Apr 13, 2010 12:20 pm

boyntonstu wrote:Find me one properly qualified high school English teacher who would grade your sentence an A.
Easy. My mother is fully qualified to teach English to A-Level standard*, and indeed has. (Although she currently teaches ICT.)
*An A-Level being the UK equivalent to US high school education.

She says there are no errors in the sentence: "Find me one properly qualified high school maths teacher who would tell you that you're using significant figures properly."
While it is not the most elegant prose, it is a perfectly acceptable use of the Queen's English, with no grammatical or spelling errors. Yes, it's not American English, but I'm British.

My British English is fully understandable, with even my deliberate "errors" equating to far less than some of the laziness that pervades the writing of some of the forum's members.

I have no intention of using American English. Yes, I will occasionally use terms which don't occur within British (such as "high school") to save confusion, but that's as far as I'll take it.
Given that I am primarily expected to write in British English, I do not want to risk getting into the habit of using American English quirks.

~~~~~

Also, one last point - even if you think my spelling of "Maths" is wrong or whatever problem(s) it is you have, it is irrelevant to the debate.

You cannot disprove a mathematical point by complaining about perceived linguistic errors in the argument!
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boyntonstu
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Tue Apr 13, 2010 2:57 pm

Ragnarok wrote:
boyntonstu wrote:Find me one properly qualified high school English teacher who would grade your sentence an A.
Easy. My mother is fully qualified to teach English to A-Level standard*, and indeed has. (Although she currently teaches ICT.)
*An A-Level being the UK equivalent to US high school education.

She says there are no errors in the sentence: "Find me one properly qualified high school maths teacher who would tell you that you're using significant figures properly." /quote]

Thanks, I learned something new.

I have never heard the word "maths" before.

Main Entry: maths
Pronunciation: \ˈmaths\
Function: noun plural
Date: 1911

chiefly British : mathematics

There are many problems in communicating between British and Americans because of the differences in meanings of the same word.

For example: A Billion is not the same for both countries.

They are 1,000 times apart.

I also completely agree with you in pointing out accuracy, precision, and significant numbers. You were 100% correct.

The topic is " Why and when to use Grain as a unit of weight measurement."

The topic is not why I say that you or anyone else should use grains.

I prefer it.

In my country all shooters who hand load use grains.

In your country, you drive on the 'wrong' side of the road.

There are many accidents for both drivers and pedestrians who look the 'wrong' way.

As Wiki points out, there are many serious people who use grains.

I say. "Live and let live".
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Tue Apr 13, 2010 3:59 pm

boyntonstu wrote:in case you don't know it - pellets and ammo in Europe (no UK) is measured in grams..

This is an American Forum, last time I checked.

We drive on the right.

We buy all our pellets, bb's, bullets, arrows, etc. in grains.


Although I prefer the Metric system, we buy our machine screws using the English measurement, gasoline by the gallon, weight in pounds, clothe by the yard, and concrete in cubic yards.

Curiously, tires use mixed measurements.

A 225/60 16 tire has a tread width of 225 mm a sidewall height of 60% of 225 and the tire fits a 16" rims.

Try buying ammunition using grams in the U.S. and you will not be successful.

Let's agree to share knowledge. PERIOD!!!


We can all learn from each other.
Our cars are built to metric specifications and every bolt on car a car bult since the late 80s is metric
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Tue Apr 13, 2010 4:06 pm

Moonbogg wrote:Rag, you talking about avoiding nonsensical precision reminds me very much of dimensioning a drawing. I have seen people add a dimension to a drawing where the main value is in 2 decimal places, but they then add a 3 place tolerance to it, and a very specific tolerance sometimes. Its strange, because if the main value is so damn important to add a precise, specific tolerance to it then the main value should be 3 decimal places as well. Anyway, I have to deal with making judgements about precision and what is appropriate a lot and reading your post was like reading the mind of a designer...oh wait, you are a designer. lol.
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Tue Apr 13, 2010 4:21 pm

boyntonstu wrote: We buy all our pellets, bb's, bullets, arrows, etc. in grains.
Umm I don't, I live in America, and bb's are measured in grams (.12 or .2 for airsoft) and until I joined these conversations, I never used grains as a measurement of weight in my entire life, so I can't agree with you on this one.
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