Here's a link to the Calico owner's manual showing magazine loading procedure.
http://stevespages.com/pdf/calico_m100.pdf
I had the later wood stock model with the plastic pistol grip.
It was a ball to shoot, but today's prices on .22 ammo would be hard to handle the Calico fires so fast.
The red dot sight on the Calico scope mount works very well but there is a major problem.......
With the mount on the rifle you can't disassemble for cleaning without removing the mount, and that looses the zero.
Also, in order to remove the barrel on the wood stock model, the "muzzle brake" and front sight assembly has to be removed by driving out the pins, then sliding the wood forearm off before the barrel nut can be unscrewed.
Other then that the only complaint I had with the Calico was because your trigger finger is very close to the ejection port some .22 ammo would drop hot bullet lubricant right on my trigger finger and give me distracting minor burns.
One "watch-out" is the quality and type of ammo used.
My Calico would lead the barrel horribly with standard velocity ammo.
The first time I shot it, after most of a 100 round drum I noticed something striking the dirt in the berm to the side of the target.
I checked the barrel and found it almost totally blocked.
How even fragments of the bullets were exiting the barrel was a mystery.
Removal of the lead blockage was a major job and ruined a new Dewey stainless steel cleaning rod when it bent as I tried to push the leading blockage out.
Strangely, with the Remington standard velocity ammo the bore would begin to lead with the first few shots, but by firing a few rounds of Remington Golden bullet the leading would be cleaned out.
This was disappointing because I'd just gotten a deal on a 5,000 round case of standard velocity.
To show how things have changed, I was an FFL Dealer at the time, and I got a sale from a distributor for cases of Remington ammo at around $100 a case.
The Remington standard velocity didn't lead up in any other of the number of .22 firearms I owned, from revolvers and autos, to Marlin 39-A rifles and a Remington 40-X Target rifle.
I assumed the problem was something to do with the Calico barrel.