Are 177 caliber pellets available in different head sizes, I think most 177's are undersized ( from what I've read). Is there anyway or anyone who knows of 177's that fit tighter in the the breech, for instance .176, .177, .178 etc. head diameter? I've been experimenting in 5.53, 5.54 and soon 5.55 in 22 caliber, and so far it looks very promising
