I am an elderly man with not too much strength in my arms at this time in my life. I haven't shot any guns in several yrears. I would like very much to buy a 45 cal automatic and go to the range periodically to shoot it. Today I went to the gun shop and looked at a Sig 220, HK USP 45 and a Springfield 1911. I found that I had insufficient strength to pull back the slides on the Sig and the Springfield without a lot of difficult effort. However, it was very easy for me to pull back the slide on the HK. Will the Sig and Springfield be just as easy to pull back the slides after they are broken in? Will it be as easy to pull back as the HK or will the HK always be easier??