Additionally, I think that if you remove the four protrusions from the black follower it could be exchanged without disassembly of the magazine housing, although I can see no reason to install the low capacity follower.
Welcome. The orange and black parts you are referring to are called followers. I'm not at all positive but my guess would be that the orange follwer will allow 15 rounds to be loaded and the black follower would restrict the magazine to a 10 round capacity for possible competetion or other restrictions. I think the magazine needs to be disassembled to install the black follower to prevent quick installation of the high capacity orange follower where and when restricted. Time will tell about the mag well wobble.
The absolute hands down best target only .22lr rifle on a budget I've ever owned is the Russian CM-2. It's a single shot, which enhances accuracy, and competes with rifles costing three times it's price. Adjustable trigger, adjustable butt stock, hammer forged barrel. It's not what I'd call pretty but man, can that sucker shoot.
I scored 300 rounds of CCI Mini Mag at Wally World this weekend. Three boxes at $7.27 each. I'd have bought it all but they've imposed a three box limit.
I've tried snake shot in several .22lr semi-autos and it has failed to cycle everytime. I used to hunt dove with a Marlin mod 60 loaded with snake shot and had to manually cycle the rifle everytime.