"Freehold" by Micheal Z. Williamson. Similar style to Heinlein IMHO. he's Madmike on THR. Very pro gun funnily enough, knows his stuff and very polite.
James Clavell - Shogun, King Rat, Noble House, Tai Pan. Proper yarns, big enough to last a day or two each and just plain old fashioned good storytelling.
Frank Herberts Dune series. Buy them all in one go and work your way through them one by one. Epic way of wasting a week or two.
Raymond E. Feist
Some of Wilbur Smiths books.
2Hr. Airport books - jack Higgins, ken Follett, Sven Hassel, M. Z. Williamsons Sniper books.