Well as a new air gunner I think I can now say I am officially a tinkerer. A few months back I dug out an old Crosman 1377 that I purchased over 20 years ago and barely shot. In fact I forgot that I even had it until I recently got into air rifles. I saw so many videos of the various mods that folks do and decided to give it a go. Figured I might end up with something fun to shoot and would learn a bit in the process. The first thing I did was to take it apart. I managed not to lose the little spring and ball from the safety. I cleaned out the plunger tube and polished the interior until it was like glass. I also started ordering parts which I spread out over a few months. Right after Christmas I had acquired everything I wanted and had a pile of very intimidating baggies filled with "things". Somehow the task of putting it together seemed daunting. Yesterday I finally decided to do it. I rewatched a few videos, sat down at my kitchen counter and about 5 hours later I had a working carbine. Wow! So here is what I did. I replaced the sear spring with an adjustable one. I did not change out the trigger, but the adjustable sear spring made a big difference. I installed a steel breech with an aluminium bolt with an elongated probe for better air flow. I also installed a larger flow port. I installed a heavier hammer spring with a power adjust knob. I also installed an aluminium flat top valve and piston and a 24" barrel, a carbine stock with a black fore end grip and a new cap with a screw pin instead of a roll pin. Topped it all off with a UTG Bugbuster 3-9X scope. I did not have time to really shoot it and sight it in. I did fire a half dozen shots over my chrony. A 7.9 gr pellet with 10 pumps is doing 650+ fps. I have not played around with the power adjust yet. I have no real rationale for why I took on this project other then just plain enjoyment. It certainly did not save money in any way. Also, I sure as heck understand how a 1377 works 
