Gargus, If you want a good reliable semiauto, I think it comes down between the AR15 or AK47 rifles.
You will need to go with a known manufacturer that produces a quality rifle. If I were in your shoes, it would be between:
Colt6920 in 5.56/223 (AR15)
- or -
Arsenal SLR-95 7.62x39 (AK47)
Both are excellent rifles that are around $1k. You will have to choose which caliber you want based on your preference and needs. The 7.62 will have more punch and cheaper ammo, while the 5.56 is more accurate has a longer range. There are also other calibers for each rifle, but its recommended to stick with one that is easy to find and more common.
Good luck in your choice. There are plenty of options but those 2 types will narrow it down for you while keeping it easy to customize if needed.