6mm rat info needed

[shooter1970]

Im looking at a 6mm rat ar-15 what's the difference between it and the 6AR? Both use Grendel brass.

 

[NateG]

The RAT is very similar to the 6mmAR-turbo40*.

Both have short, stubby, little necks with 40* shoulder angles. I've got a 6RAT and like it a lot, though I was only running it at about 6AR loads. (28.0 of 8208 with a 105VLD at 2800fps) It shot *very* well, though I think that barrel's not long for this world. The last string I've shot with it was a 200-14X at 600 at Perry, but at 2.5k rounds, I'm not sure how much longer it'll go.