In my opinion is quite simple: at the end of the day, you'd have used much more coffee. With one kilogram of coffee beans, you should be able to make about 140 shots if you'd use 7 grams, only 100 if you use 10 grams, and in this case the cost per shot you'll pay would be almost 50% more!
http://www.slitti.com.au/blog/24_7_grams_of_coffee_or_why_you_should_be_careful_comparing_the_cost_of_coffee_beans.php
Because several coffee wholesaler in the New World are pushing baristas and cafe café owners to use, 8 9 or even 10 grams of coffee per. Shot some of them'don t even let baristas use a dosed, grinder they just reccommend to fill the group until is, full and the add some! more
http://www.slitti.com.au/blog/24_7_grams_of_coffee_or_why_you_should_be_careful_comparing_the_cost_of_coffee_beans.php
It will fit 25 or 26 grams to the maximum. I find that anything between 22-25 grams grams produces an alarmingly strong double shot (assume 60ml max extraction) in 30 seconds. Great if you need to stay awake all night!! 8^) So I only use it when my friends want a tripple ristretto.
http://coffeesnobs.com.au/general-coffee-related/34313-how-many-grams-double-shot.html
How many oz of ground coffee in a shot of espresso?   Traditionally a barista will use 7-9 grams (about 1/4 oz.) to make a single shot of espresso (approx. 1.25-1.75 oz of liquid coffee, depending on taste). To prepare a … double espresso, one usually uses 15-18 grams of ground coffee to produce 3.0-3.5 oz of liquid espresso. 7 people found this useful.
http://www.answers.com/Q/How_many_grams_of_coffee_in_1_shot_of_espresso
Let us consider a case of a short black-a double expresso or double ristretto. At home I have a luxury of accurate weight measures for my double espresso/ristretto. I have digital scales with 0.1 grams accuracy (~$90 in many electoris stores). This helps to ensure 100% repeatable results.
http://coffeesnobs.com.au/general-coffee-related/34313-how-many-grams-double-shot.html
However, where espresso is brewed at a pace delivering roughly 1.5 ounces over 25 seconds (or 3 ounces for a double in 25 seconds), cafe cafè cr me is brewed at a faster pace as much as 5 ounces or more in 25 to 30. Seconds this is achieved by altering the grind of the coffee to allow for more flow through into the. cup
http://www.coffeegeek.com/opinions/markprince/07-20-2004
How many ounces of coffee grounds to 1 oz of espresso?   7 to 10 grams (¼ to ⅓ ounce) of ground coffee for a single shot or 12 to 18 grams (⅜ to ⅝ ounces) for a double shot.
http://www.answers.com/Q/How_many_grams_of_coffee_in_1_shot_of_espresso
Why? Because 7 grams is the exact dose of coffee required to brew a shot of espresso, even if-depending on the coffee, the machine, the grinder, the weather... - you should probably find the perfect dose for you in the range 6.6 to 7.2 grams.
http://www.slitti.com.au/blog/24_7_grams_of_coffee_or_why_you_should_be_careful_comparing_the_cost_of_coffee_beans.php
I have a Synesso ridge-less double basket, rated at, I think, 21 grams. This is what I use 90% of the time to make my double espresso. I have used it with as little as 16-17 grams and at most 21 grams, this is the limit. It does not fit any more than 21 grams in my experience. I also have a standard Rancilio Silvia double-basket which can only fit 18 grams maximum.
http://coffeesnobs.com.au/general-coffee-related/34313-how-many-grams-double-shot.html
When it comes to espresso blends arabica coffee beans are recommended and mostly used. Some professional barista's even consider adding a little bit of high quality robusta beans to enhance the crema, usually 10-15%. Proper Dose for 1 shot should be between 7-9 grams, and 14-18 grams for a double shot. 1 oz of Water: A 1 oz shot is considered the median, and is often recommended; however, this varies from person to person since in the end it's all about the taste. Some prefer their shots Ristretto, which is about 3/4 of an ounce. Also, on the other hand, others prefer anywhere from 1 ¼ - 1 ½ ounce shots.
http://www.e-importz.com/perfect-espresso-shot.php
how many grams in a shot of espresso
A shot of Espresso contains 7 to 9 grams. There are 7 to 9 grams in a shot of espresso.