Budget is around $1000 for the rifle. A custom build is out of the question. I don't want to invest $2-$3k in just the rifle. And I lack the knowledge of doing a custom build anyways. There are WAY too many options out there and it would take me 2 years of research to even come close to making a decision. I'd rather buy something factory made, from a reputable brand and most likely learn to reload with it. I don't shoot competition, this is just for my own enjoyment for my Mondays at the range. If I can shoot under 1 moa fairly consistently out to 300 yards, I'd probably be content with that.
Here is some of my experience with factory 223 rifles-
Ruger American Ranch- Early model, shot terrible even with match ammo. Action is nice, trigger is okay, stock is tupperware garbage. A lot of people don't like the mags. I wouldn't go with an AR mag as it limits you to short bullets. They claim they are 5.56 compatible.
Tikka Sporter- Pricey rifle but it will shoot 1/2 MOA or better out of the box with my reloads. Most Tikka's that I have experience with shoot really well. Mags only allow for 2.260 length ammo. If you want to shoot the long heavy bullets, you need to modify the mags, single load, or upgrade to to chassis that takes AICS mags. I got lucky and found a guy that was getting rid of his 3 that had been modified. Never tried 5.56 loads.
Remington 783- I paid $250 after rebate. The first one shot terrible but the replacement Remington sent wlll hover around 0.6 MOA with my reloads. Action is smooth and I like the trigger, magazine is well made, stock is probably the best of all the budget rifles. They make them with 16 and 22" barrels. It will run 5.56 ammo without any issues. A solid rifle for the price.
Howa Mini Action with 1:8 Heavy barrel- fun little gun. Shoots 3/4 MOA. If you want something for target use, this wouldn't be my first choice. It does not like warm loads so definitely no 5.56.
Remington 700 LTR- I wish this had a better magazine and a 1:8 twist but I love the way it shoots and handles with the 20" barrel. Nice old school rifle.
Mossberg Predator- This gun shot fantastic with 68/69 match bullets, 1/2 MOA or better. Action was sloppy and the plastic trigger guard cracked. Laminated stock was really nice. It didn't fees reliably from the original or any other AR mag I put in it.
Remington 700 16.5" SPS Tactical- I picked this up cheap and was going to build it into something but may just keep it to way it is. I put a 1-6X scope on it and shoot steel out to 600. The internal Remington 700 magazine doesn't work that well with 223. Upgraded DBM and a good magazine would make this a sweet setup.
Remington 700 Remage setup with a 22" 1:7 stainless barrel- I bought the action and had the barrel headspaced using the barrel nut system, then put it in a Magpul hunter stock. The magazine system worked great and there is a lot of aftermarket support for the AICS mags, but I could never get the best accuracy from the stock. There is just too much plastic in my opinion. I ended up bedding it in a Boyd's and it shoots better. It gets fed 75 and 80 ELD.