Just about all the posts here will tell you that most Minis are not particularly accurate. Mini bashing is a popular sport. Some of the folks who bash the Mini have actually owned or shot one.
Newer ones are reported to be better, and the target version with barrel tuner is reported to shoot quite well.
It is not a military rifle, although it has been widely used by police and paramilitary organizations.
It is possible to rework a Mini so that it is quite accurate. Can be quite expensive. There are rebuilders who guarantee real accuracy.