My friend Tom has one of these loaders for his .22LR AR. It works so well and it is made in the USA. Even better for me, they are made locally here in Pennsylvania.
The Lightning Grip loader is not terribly expensive. It sells for $22.50 and you need to buy a $6.00 adapter for what ever magazine you want to load.
Here is their website.
I got mine with a M&P 15-22 adapter. I have a MFT magazine coupler holding two M&P mags together. It makes it difficult to load a full 25 rounds into the magazine. However, with the Lightning Grip, I can now load them full and faster. Take a look at the video below.