So if you want a semi-auto that is semi-accurate and reliable. All can be put in stocks that resemble your military style ones you are humping on. Here is what I own or have shot
1. The starter: Ruger 10/22 .22lr , or its more expensive tactical varieties. I just bought the basic, put it in a tapco stock, added bolt buffer, power custom hammer, red dot and auto bolt release. $500-700 and its a beauty. Accuracy is limited to your scope, and range realistically drops off around 150 yards. Bull barrelled and tricked out they can reach out farther with decent accuracy. Red dot is only good to around 50-100 yards. You can tune these things to do whatever you need, and they are really great in my opinion.
2. The Mini-14. .223 Can be accurate, can be put in a tactical stock. Very reliable, solid and well built. Around $700 Some dislike, others really praise these. Rounds are more expensive then the .22LR and 7.62x39mm above and below.
3. CZ-858. 7.62x39 Accuracy is questionable, I use iron sights and its okay out to 100 yards. Super reliable, and well built. Around $700. And yes they make cool stocks for these as well. I have one and love it, I dont even need a black stock either!
4. SKS 7.62x39mm Can be fairly accurate, though I don't think on par with AR types because of fitting tolerances and the simplicity of its design. Super reliable though. You can trick it out with a few hundred bucks, and its cost is anywhere from $75 on sale to over $300 at retail. These are neat cold war relics.
Thats all the personal experience I can give on soem semis.