The Air Venturi QB series Tune Kit allows you to increase your .177 cal QB or AR20 air rifle by up to 100 fps (depending on pellet weight & shape). The kit comes with detailed instructions to allow anyone to tune their gun at a much lower price than having it tuned professionally. With the extra 100 fps you can extend the distance you can shoot as well as having the wind effect your shots less.
I have seen a least a 75 fps improvement with this mod. kit and if I add a stronger spring the fps should be closer to a 150 fps over stock.
ProsMore fps, IT'S LIKE A PROFESSIONAL TUNE
ConsNONE YOU ARE IMPROVING THE GUN
Best UsesIf one wants to get more power and a do it your self tune this is the one to do it.
By Robert G.
QB Tune kit for .177
June 24, 2016
The QB78 tune kit was easy to put in and I love the extra power it now has.
Rancho Cucamonga, CA
June 6, 2016
Bought this kit along with my QB78 Deluxe! Didn't regret it at all! If you have issues installing it, just google it or YT it. Upon installing, I will say you will shoot a lot lesser than before BUT it increases your fps of your QB!
Good if your handy.
June 6, 2016
I purchased this as any one else would that wants more power. I researched this enough to believe it does as described with out having away to verify this myself. With out a chrony you don't know for sure the exact benefit you get. I have diy upgraded a crosman 2250. With that one I shot a big candle tweaked the gun and shot it again and so on. It stuck deeper with every change I made. With my qb78 I installed this right out of the box so I cannot praise it's power difference. I can say the stock bolt however more restrictive seems to be thought out better. The tune kit bolt kept binding in my breech. After a few times of assembling & disassembling I realized it wasn't me. 1st I sanded all of the scratched areas of the bolt from working it in the breech. No change so then I took all of the blueing off. No change. Then I noticed that the business end of the bolt was not tapered. The thick part. If you laid the bolts side by side you will notice. I tapered it with a file and now all is well. It was still stiff at first but as eased up since. Still worth buying. If you can install this you can adjust it to suit your breech.
ProsWorth the time for fps gain. Keep in mind your shot count will drop.
ConsBolt needs to be tapered. It may not affect all but it sure did mine.