some Chinese cash coins, new field to me

Ive had these in the back of my desk for some time. Ive just decided to look to this subject, would be glad of any pointers.

1- 4.2g,22mm; 2- 3.6g,23.3mm; 3- 4.0g, 22.6mm

4- 2.7g,21.5mm; 5- 1.18g,16.75mm; 6- 2.86g, 24mm

7-2.9g, 24.6mm

1,2 and 3 all appear to be N#1133

is there really that much variability, or are some fakes?

6 and 7 both appear to be N#6817

mintage over a billion…

5 is this N#35119 

Coin of the last Qing dynasy emperor.

Hello

you are right in your identification

1-22.207 

2-22.203

3-22.204 ( a little doubt for  this one they are known to be poor coin but never seen one with that kind of bad made hole)

4-22.225

Lots of varieties for the Qian long tong bao

And the other one are ok too

Welcome to Chinese cash coins :))

thank you Gros, for your help. 

what is the meaning of the different reverse characters, Boo-guwang, Boo-chiowan, etc…?

They are the mint name

But sometime with th same mint name they wer made at different place 

With some difference in the caracters 

So fun😁

gros

They are the mint name

Understand thanks . will learn them carefully🧐