I wanted to try the 150's because I just got a second RUM and my sendero shoots a 180 gr combind techinology bullet, great bullet, but I don't want 2 guns that shoot the same, I wanted one to be a little lighter and faster, So with the feed back I am going to try the barnes X Tripple shock 150's in the new RUM. But so far with the 180's the new one shoots as good as the sendero. I am very pleased. MUZZ you need one of these!!!!! bad to the bone. But I will tell you one thing the lighter gun packs a punch a little hard on the shoulder, But I can handle it.:<)