Well whats a fellow to do when he loves shooting airguns and he finds a "deal"? Naturallly buy it! So having had several QB78's in the past all sold only due to the way C02 acts up with temp changes I thought a QB79 w/Ninja tank might be fun, and yes it was even if it was in .22. Nothing wrong with .22 but I do already have a true sub-MOA .22 and I also have a love for shooting FT so this one need to become a .177 so I started looking around for parts and talking to a good friend who is a bit of an airgun wizzard/craftsman. It did seem a good idea to add a second barrel set screw and float the barrel, QB barrels being somewhat hit or miss (and I need to "apply directly to target" all my pellets) a cut and crown also seemed a good idea. Also whilst a shooter will adapt to whatever stock they have a slightly better stock design lends itself well to FT, so I was sold on that idea too. While I cant see too much danger in the Ninja reg letting loose without blowing the 1800psi burst disc, sthuff does happen and mainly the factory QB79 attachment screws leave a little to be desired and the 79 tube offer little in the way of head room (er expansion chamber if running Co2) and it seems the answer there is to use a cut QB78 tube with several beefy counter sunk bolts for attachment and if you are going to drill tap and counter sink a few bolts why not add some to the valve as well "just in case" a peerson might want to play with upping the reg output (I dont really plan on that but heck you never know).
As we say in the South, "well, last weekend it all came together", modded valve for flow, light hammer/spring, attachment screws added every where, cut and crowned barrel, factory stock modded to an FT stock, and a Leapers 3-9x40 mil-dot scope. And just in time for the FT match this comong weekend at the GOB club in Pulaski TN, ya buddy!
Decided not to use a brass screw to re-crown the barrel:

cut 78 tube w/79 block:

nice to have a couple hundred shots between fills:

and an FT rifle need to sit flat:

well and after you apply divers grease to something you wanted to paint (opps) sometimes you need to just go with it and hope for the best:

Now all I need to do is adjust David Slades scope everytime he turns around and I just might put on a pretty good showing in International class FT this weekend.
May you all enjoy your QB's as much as we do.
John