for Kingman Spyders
by Billy Goodman
What it is
The Shocktech Twist Bolt
is designed to offer the ability to remove the bolt from the gun with just
a turn of the rear cocking handle. Removing the bolt without having to
disassemble the gun allows easy cleaning on the field, giving access to
the complete breech/bore area of the gun. The rear-cocking style of bolt
also means no more having to keep up with the side cocking screw for users
of older Spyders. Newer Spyders not only have rear cocking, but also have
quick strip pins allowing the easy removal of the internal parts. However
even these guns can see a benefit from the Shocktech Twist Bolt because
it keeps the user from having to remove the hammer, spring and other internal
parts for an on-field cleaning.
Physical Stuff
The bolt itself has an aluminum
rear section and delrin front section. The front of the delrin section
is a three-hole "venturi" type design. Unlike most bolts, the Shocktech
unit has no o-rings. Turning the rear cocking handle retracts the steel
link pin attached to the bolt, allowing the unit to be pulled from the
rear of the gun.
Installation
Installation
should be fairly straightforward, but unfortunately it hasn't been with
any of the three Shocktech bolts we purchased on any of the six Spyders
on which we have tried them. While simply swapping the Shocktech unit for
the stock bolt is easy, making the bolt work as intended is a different
story. On every gun the retracted link pin could not get smoothly past
the lower end cap (the cap which holds the velocity adjustment screw).
While on one gun it was a close scrape, on all of the others it was a complete
impasse. On one of the guns, a Spyder TL+ with a field strip pin, the field
strip pin itself blocked the retracted link pin and the removal of the
Shocktech bolt.
Our
solution
to fix the problem was to flatten out the top of the end caps enough to
let the link pin pass smoothly, and in the case of the field strip pin
on the TL+, to cut a notch allowing the link pin to pass. The modifications
were done with a Dremel tool or a bench grinder.
A side note: as with any
rear-cocking bolt installed on a gun which was previous side-cocking, the
end cap on the upper tube has to be removed. On some Spyders the upper
end cap is also where the mounting screw for the sight rail is located,
so switching to any rear-cocking design may mean the elimination of the
stock sight rail.
Performance
The use of the bolt does
affect the performance of the gun itself, necessitating a "re-tuning" of
the gun. While on one gun the bolt caused a noticeable drop in velocity,
on another it caused a refusal to re-cock (Switching back to the stock
bolt immediately addressed the problems, indicating the Shocktech bolt
was indeed the culprit). A simple spring change fixed the problems there.
As far as an effect on the
performance of the ball out of the barrel, there is no noticeable difference.
However, that's not what this bolt is about. The main point of the bolt
is quick field stripping. Once the modifications above are handled, the
system works well. A simple twist and the bolt slides right out of the
back of the gun, allowing the user to run a cleaning tool all of the way
through. For "in-game" ball breaks, this allows a very fast and thorough
cleaning process.
A few operational notes:
1)
We have found it's easiest to remove the bolt when the bolt/hammer combo
are in a "cocked" (farthest to the rear) position.
2) If the internal action
of the bolt (which controls the retractable link pin) starts to stiffen
up a bit, a couple of drops of oil will smooth up the process. The process
also binds if the hex screw which holds it in place is overtightened.
Another side note: as the
owner of the only vertical feed gun in the bunch, it's my observation that
the using the Shocktech bolt does cause more blow-back of gas up the ball
feed tube, which can adversely effect the feeding of balls. The problem
isn't really noticeable on powerfeed guns.
Opinion
The idea behind the Shocktech
Twist bolt is appealing, but the implementation is somewhat less than ideal.
In all honesty, some of that could be because of the inconsistencies in
Spyder design. There may be particular types of Spyders (afterall, there
are so many) the unit will drop right into and work perfectly, however,
it's marketed as "for Spyders", not for a specific model. Considering the
modifications we had to make, the bolt is not something I'd call a "drop-in"
piece and I couldn't recommend it to most people without pointing out the
fact that some grinding work will likely be needed to get things working
properly, not to mention spring changes. Once you do those things, it's
a really convenient feature to have. But if you're expecting to simply
pull your old Spyder bolt out, stick this one in, and immediately have
a cool field stripping system, you're likely to be disappointed.