This type of rifle is known as a Break Barrel Cocking rifle. It's not a BB gun it's a Pellet Rifle that fires .177 caliber pellets. It was made between 1971 - 1974. It was made in Scotland by the Milbro Brothers and sold under the Daisy Brand name.
To "load and cock" the rifle. With your right hand hold the rifle by the grip right behind the trigger. (KEEP you finger OFF the trigger) With your left hand grab the very end of the barrel and yank down on it. It will break open the barrel at the breech. Pull it all the way down (Like you are folding it in half,) until you feel it cock with a click. Load the Pellet into the open breech (rear of the open barrel) then pull the barrel back up into the firing position.
you are now ready to shoot. If you have a safety, put in on Fire.
The Daisy model 225 was made by Milbro of Scotland for Daisy between 1971-1974
Consult the user's manual
Are you asking about a gun or a rifle. Which model are you asking about. Daisy had made over a 100 different BB guns and rifles
The model 288 is a 24 shot BB gun that is loaded from the right side. There is a slide cover directly above the trigger that you slide forward to load the BB's
The model 102 rifle is loaded by removing the cap on the end of the barrel.
It's a BB Gun.
Which model, what is the condition of the BB gun or is it a BB rifle..
It sounds like a Daisy BB gun.
Your best bet is to ask Daisy directly. Daisy offers a free service to tell you about your old Daisy. See the link below.
Get a manual from Daisy. Daisy Outdoor Products P.O. Box 220 Rogers, Arkansas 72757-0220 (800) 643-3458
Daisy started in 1895.
All Daisy model 25's load the same. You unscrew he end of the barrel and pull out the loading tube. It's pretty self evident when you see it.