I've never had any problems fully loading my factory Browning mags, MecGar 20 rd (actually 21
) or Ramline 15 rd mags.
It does take a take stout pull to load the chamber, however. Neither my mom nor dad could do it.
Mauser Werke, Schmidt-Rubin, Colt, Walther, HK, Weatherby, Browning, Ruger, Beretta, Savage, Bushmaster, Marlin, Mossberg, Remington, PTR, Saiga, S&W, Sig Sauer....a few friends of mine