B12 Home Tune resultsMay 15 2012 at 9:13 PM
|Mike B (Login mjb108)|
Just tuned one of two .177 B12s I got from Mike Melick a few weeks back. I gave it a full deburr and lube, added a washer to the piston and two to the spring guide, and sized the seal a bit. It's shooting 520fps with CPLs. Seems a wee bit slow but shoots fine. A little buzzy, but the rear guide wasn't very tight to begin with.
I plan to put some shrink tube on the rear guide.
About the seal - it would leak a tiny bit of air as I compressed it by hand. do you think I'd be doing better to replace it with a Maccari seal?
Accurate as hell at 25 feet.
the question is, am I likely to pick up velocity with the new seal?
|May 16 2012, 6:50 PM |
Also, I compared the innards to a 1980/81 HW30 with the Rekord trigger, and it's surprising how similar they are (and different, too, I guess). I'll have to figure out how to post pictures and show you.
Most interesting is that the piston is much heavier in the B12, the springs are almost identical, but the B12 has over 1" of spacing available, compared to less than half that in the HW30. Seems to answer my previous question... heavier piston, less energy stored in the spring.... maybe my velocity is just about right.
Anyone lighten the piston on one of these? You could shorten the piston rod by 3/4" of an inch, which would increase preload, lighten the piston (to what the HW30 piston weighs, nearly) and lengthen the stroke all in one fell swoop! Not sure the cocking arm and slot in the fore arm would allow you to cock it, however...
Thinking out loud.
Where is everyone?
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