Military Sci-Fi books
Here are 48 books with a lot of military sci-fi, starting with Old Man's War, Dauntless and First and Only.
Old Man's WarJohn Scalzi
DauntlessJack Campbell
First and OnlyDan Abnett
ArmorJohn Steakley
CourageousJack Campbell
Galaxy in FlamesBen Counter
Valor's ChoiceTanya Huff
HelsreachAaron Dembski-Bowden
Starship TroopersRobert A. Heinlein
HALO: Hunters in the DarkPeter David
In Enemy HandsDavid Weber
Ender's GameOrson Scott Card
SkywardBrandon Sanderson
Halo: Contact HarvestJoseph Staten
SpecOpsCraig Alanson
Terms of EnlistmentMarko Kloos
Lines of DepartureMarko Kloos
On Basilisk StationDavid Weber
Horus RisingDan Abnett
True ColorsKaren Traviss
The Heart of ValorTanya Huff
The Better Part of ValorTanya Huff
Halo: GlasslandsKaren Traviss
ConstitutionNick Webb
Shadow of FreedomDavid Weber
Dust WorldB.V. Larson
Storm from the ShadowsDavid Weber
Fields of FireMarko Kloos
Valor's TrialTanya Huff
Tarnished KnightJack Campbell
LeviathanJack Campbell
Center of GravityIan Douglas
FreeholdMichael Z. Williamson
Tech WorldB.V. Larson
501stKaren Traviss
BoloKeith Laumer
Prospero BurnsDan Abnett
DeserterMike Shepherd
The FoundingDan Abnett
Rich Man's WarElliott Kay
MutineerMike Shepherd
Aspho FieldsKaren Traviss
GhostmakerDan Abnett
ParadiseCraig Alanson
NecropolisDan Abnett
SingularityIan Douglas
Valkyrie RisingEvan Currie
AnnihilationB.V. Larson