- Manufacturer AGD
- Condition New
- Accessories Type AGD
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.
Pros
Worth the time for fps gain. Keep in mind your shot count will drop.
Cons
Bolt needs to be tapered. It may not affect all but it sure did mine.
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.
Pros
More fps, IT'S LIKE A PROFESSIONAL TUNE
Cons
NONE YOU ARE IMPROVING THE GUN