Hmm so it seems no more 4.53's. Mine was really enjoying them however I found that they required allot of prep to perform at their best. Try Jsb express/mozzies as my Pt 3 loves 4.53's and mozzies. I gave the barrel a clean and after about 30 shots leading in got some nice groups this morning. 8mm at 45 yards and a nice 10mm 5 shot group at 55. That'll do me. Predictable in the wind too if your barrel likes them.