Assuming you mean bullet grains, which is how most preloaded ammo is categorized, the answer is going to depend on what you intend to use it for. Generally, the 124 grain JHPs are a good all around choice. The 115 gr bullets are OK for hunting small animals or just plinking.
It depends on your intended use, skill level and pocketbook.
You will have to define what you want to use the weapon for. Loads vary from 90 - 147 grain.
Glock 22
No cause its too short for gun the glock 17bis a bigger size and thr glock 19 is the compact size.
Glock 17
He describes it as a "Glock .40", which would mean the one he carried was the Glock 22.
The most popular gun made by Glock seems to be the 9mm for people who use it recreationally. Police officers, and the like, seem to prefer the 40 caliber.
Glock 21
It was a full auto Glock 18
That's like asking "What is the best shoe?" Handguns must be selected on the basis of use, size, fit and reliability. Do some research on firearms websites and in the library, pick out some to try and then call some gunshops and see if you can rent them and get training at a range.i would say any type of glock The problem with saying "any type of Glock" is, it depends on what the original poster wants to do with the gun. If he is shooting 25 and 50 yard bulls-eye competition, Glock is a horrible choice, and he'll never win a match with one. If he wants a small pocket gun, Glock is a horrible choice. Glock is a good gun, but it not the answer to every question.
Police most often use the 9mm Glock 17 or the .40 S&W Glock 22. The glock 17 magazine holds 17 rounds (+1 in the chamber), while the Glock 22 holds 15(+1).
You would have to define best- what what use.