I have been in seach of the right rifle and I have come down to the AR. It seams that you have alot you can do from the base. I want to build my first. I like to be able to shoot 600 - 1000 yds. Is there a difference in the lowers for a .223 then the .308 I want to be able to build my base off of the .308 but want to be able to change a few thing to have a different setup between distant and close combat.  what parts come into play for excepting the different rounds.

Thanks
Matt

There is a huge difference in the construction of a .223 lower and the .308 lower.  They are not compatible.  You have to choose between on or the other or both.

For 600-1000yds, there's no real reason to stick with .223/5.56.  .308 will serve you much better for distances like that.

With that being said is there less parts out there to make what ever  for the .308 or would I be better just to wait my time and make 2 different rifles. Im also guessing then the parts for a .308 will cost more then the .223?

Quoted: With that being said is there less parts out there to make what ever  for the .308 or would I be better just to wait my time and make 2 different rifles. Im also guessing then the parts for a .308 will cost more then the .223?

.308 parts cost more, but not that much more.

You can make AR-10 carbines.  ADCO has one and it is sweet.  He's running it in carbine competitions.  You could very easily build/buy one rifle, then build a dedicated carbine upper for it and be where you want to be.

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