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Aluminum Flat Top Valve & Piston Kit
For Crosman 1322 1377 2289 P1322
P1377 |
MAY
2021 UPDATE: The piston now features two o-rings for better
compression. Looks a lot more professional, too.
MAY 2021 UPDATE x2: A solid brass
piston is now available. It's fancier. It's heavier. It's bling that only
you know is inside...?
- The Flat Top upgrades are immensely
popular with Crosman pumper enthusiasts. The idea is that by giving the
gun a larger air reservoir, you can do more work per pump, resulting in
the same shot velocity with FEWER pumps. Or, increase velocity with the
same number of pumps over OEM.
- You can buy just the Flat Top Valve,
just the Piston or the Complete Kit.
- Note that you should not install just
a Flat Piston with an OEM valve. The gun won't cock completely and will
be useless.
- You can, however, install just the
Valve.
- But the smart move is to install the
complete kit.
- Want even more mods? Consider the
Flat Man's Pack, which is the
Flat Top Kit + Power Spring + Max Flow
Bushing.
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- The Flat Top Valve is an OEM Crosman
valve that has been heavily modified.
- First, we put it on the mill and angle
the exhaust so the escaping air doesn't have to make a hard bend.
- After that, we straighten up the
exhaust hole with a nice six-fluted bit.
- Then, we flatten the face to allow
more air to be pressurized per pump.
- Finally, we remove as many machining
marks as we can to make a perfectly smooth exterior.
- And, of course, the valve is cleaned
and polished prior to reassembly with BRAND NEW o-rings.
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- This is the Flat Top Piston. It is
7075 aluminum milled from scratch.

This is the older single o-ring style. All
shipments will feature double o-ring pistons as shown below. |
- And here is the complete kit.



Older single o-ring style. |
- Here is the kit with the brass piston.
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Flat Top BRASS
Piston Kit
$79.99
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Flat Top Valve Only
$34.99
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You can buy just the FT
Valve or Piston for specific use purposes, but understand
you're on your own with that purchase. They're not designed to be used
separately. |
Flat Top Aluminum Piston Only
$39.99
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Flat Top BRASS Piston Only
$49.99
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