@Hotshot: I definitely second Tenx on the modifications part.
The Gsmith replacements will improve over the rifle's performance, but will also make it harder to cock and rougher to shoot.
Get used to the gun first. Once you get comfortable and the rifle is broken in, you will have an idea of the performance - Both your's and the weapon's. If then, you feel there is room for improvement, practice more
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If there is still more room for improvement, get the Gsmith parts.
Always remember one thing, a pellet travelling at 400fps and hitting the target is any day better than one whooshing along at 1000fps no where near the target!
Gsmith pellets are heavier than the regular lot you get. They are of considerably better quality too and also more consistent in shape. Get a pack, see if you like it. I suggest the Domed ones. Being heavier, the range will be reduced. But if you stick with the learning curve Rusty suggested, distance wont matter to you.
I'm a big sucker for mods too
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But give it some time and you'll have fun. Dont think of all this for now, it spoils the fun. Enjoy your gun, plink more. Kill the spring with all the use and then change it. GSmith aint going nowhere. Even if they do, we'll find you springs and washers and what not!
Mo.