Quote Originally Posted by bellavite1 View Post
As I suspect many of us, I am intrigued at the idea of shooting a 30 cal bullet out of an AR.
I do have a few questions, however, that somebody hopefully can answer:

I do realize that a 300 BLK is not a 308, but what is the feasability of using it as a medium range cartridge (say 500yds)?

What kind of accuracy can be expected in this application?
I can tipically hold 1/3 MOA a 100 yds with my 308, sometimes out to 300 yds.

Using a medium weight bullet, say around 150gr, what kind of velocity can be expected from a 20" barrel?

Does a 20" barrel in this caliber even exist?

Yes, I know it is a round supposed to be for CQB, but it would be nice to be able to convert my 20" .556 and have a lightweight med range precision weapon...

Any imput?
1. Max effective range according to US Gov is 440 yds...can shoot further, but bullet trajectory is a BITCH.
2. Very accurate round...but accuracy will suffer some due to shorter barrel lengths
3. Longest barrel I have seen/heard of is 16"...custom could go longer, but generally not recommended.
4. You can push 125 gr bullet to around 2300 fps...130 gr to around 2200 fps..150 gr to near 2100 fps from a 16 inch barrel...due to powders used for this round a longer barrel isn't going to give much more velocity.
5. Converting a 20" can be done, but you probably will need to swap in a carbine buffer, spring, and spacer (if you have a standard rifle tube on you lower)