Not familiar with the ATR 100. The M44 is a fine weapon that will soon begin to rise in value now that they are no being found everywhere. The Mossberg 500A is an excellent shotgun that can be used for hunting or HD, stop by the shotgun forum if you ever need any advice. The Ruger 10/22 is considered by some to be the best of of 22's, not me personally, but by most. You are doing fine.
You can now move towards the older rifles such as the Garands and such or newer guns such as the AR's. Decisions, decisions. Reloading is always a possibility too.
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