Cal .177
Any air gun or rifle that uses a .177 Caliber pellet can use the Gamo .177 Red Fire Pellet. No matter who makes the air gun. The Caliber .177 is universal to all .177 caliber pellet guns or rifles.
The 620 is a 4.5mm or .177 caliber pellet rifle and is rated around 450 FPS.
I assume you are asking about air guns, if so then it would be helpful if you stated the model. Most air guns can accept all weights of pellet grains as long as the pellet is the correct caliber. In other words you can not use a .22 pellet in a .177 caliber pellet gun but you can use different weight pellets as long as they are .177 for that gun.
Pellet guns tend to come in two standard caliber sizes. The first smaller caliber is the most common for pellets guns and is .177 caliber. The second is .22 caliber that can be found on some higher powered pellet gun models.
Simple: With the Safety On. Slide a cleaning rod down the barrel to dislodge the pellet from the loading port. Yes there are cleaning rods for pellet guns. They are 177 caliber.
No. Bad Idea! BB's a .177 in size not .22
It depends on the model and the caliber of the Pellet gun.
If you are talking about a PCP (PreCharged Pneumatic) rifle. With a .45 caliber pellet, then "Yes" It can. I don't believe there is a 40 Caliber pellet gun.
It would be worth around $65 in Excellent shape.
Lets get something straight. There are BB guns / Rifles and there are Pellet guns / Rifles and there are a few BB & pellet rifle combinations. Most BB guns are .177 Caliber, there are a very few that are .22 caliber. Pellet gun & Rifles come in .177, .20, .22, .25, 9 mm, 40 Caliber, and 50 Caliber. The last 3 calibers are usually high powered air rifles in the PCP class of rifles (PreCharged Pneumatic) they require a special pump or SCUBA tank to charge them. So Yes there are calibers much larger than .177
I've see a lot of thing about pellet guns. So far the answer is "NO". However one of the smallest pellet guns currently is the Walther PPK/S.