Incredibly difficult to load - SGM Tactical .45 Cal Glock Compatible 26 Round Pistol Magazine

I ordered 2 of these 26 round mags, and I can't get more than 21 rounds into them, even with a speed loader. The spring tension is ridiculous on these, and it's almost a struggle to even get the first round in by hand without a speed loader. I was only able to get 10 in by hand after a great struggle. I'm a mechanic by trade so grip strength is not the problem here.

They're also only labeled up to 24 rounds and not 26, not sure if that's supposed to be that way or not.