How to port a Airforce Airgun’s valve stem
I know most of you guys have done all this stuff long ago im only making the videos to try and help out new people comming to TAG this idea was from a member here called LURKER #1 and it is just a way to get a little extra fps from the valve you already have this is in no way a replacment to the custom valves some of you guys are making hope this video helps someone.
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Yeah my Tophat is as far out as it can go and still close the breach
oh, I forgot to thank you for the excellent documentation.
The documentation is priceless ❗
I didn’t really expect that much detail.
One other thing you might try is to turn the tophat out a little and avoid having the mid to high power wheel settings. The mid to high power wheel settings messed with trigger pull and safety operation on my first Condor.
Even with the top hat turned out more to compensate for the o-ring, the psi useage per shot should have improved.
Lol as long as it helps someone you know
Hey PANDEMIC you really got their attention ❗
SILENCE IS GOLDEN.
Some that already ported their valves are probably back at the bench adding some new touches.
And those that hadn’t ported before are all out shopping for a rotary tool and some files.
Great job with your videos ❗
Definitely a gain with the ported valve stem ❗
Much less gain at lower power wheel settings and an increasing gain at higher settings.
Appears to be a good match for your setup PANDEMIC.
so here are my findings
Fill 2500psi 15 shots PW-0 normal valve
1-989.3
2-978.5
3-985.1
4-982.3
5-942.7
6-974.9
7-982.5
8-976.9
9-977.3
10-970.0
11-970.8
12-967.0
13-961.9
14-959.5
15-957.4
Fill 2500psi 15 shots PW-0 Ported Valve
1-989.1
2-990.2
3-990.5
4-991.3
5-992.4
6-993.2
7-995.4
8-997.6
9-994.9
10-997.5
11-994.0
12-991.3
13-992.9
14-976.2
15-970.1
so at this point only 10 fps extra but im shooting a condor with a 12″ .22 barrel so i was just wasting alot or air so i put a o-ring under the tophat to see if it would show what the ported valve can do with out waisting so much air here is the numbers
Fill 2500psi 10 shots PW-6 normal valve with o-ring
1-577.4
2-574.6
3-574.5
4-570.1
5-583.4
6-574.5
7-571.5
8-567.6
9-567.8
10-570.6
Fill 2500psi 10 shots PW-6 ported valve with o-ring
1-712.4
2-706.3
3-703.6
4-705.8
5-708.8
6-710.1
7-708.8
8-703.7
9-704.6
10-711.0
This is about 140fps difference
Fill 2500psi 5 shots PW-12 normal valve with o-ring
1-644.7
2-648.5
3-657.4
4-646.7
5-638.8
Fill 2500psi 5 shots PW-12 ported valve with o-ring
1-791.2
2-793.4
3-787.6
4-786.4
5-785.5
Still looking at like a 130fps difference
All testing was done with 14.3gn CPHP
$ 😆 $
By weight the set screws are at least 10 X the cost of gold ❗
for $15 i thought i would have got the whole set up top hat screws valve stem
Used to be you didn’t get the set screws either when you order it with a top hat.
it would be a good idea to to get a couple extra set screws. They disappear so easily.
by the way when you buy a valve stem from airforce you do not get a top hat with it just to let you know
Nicely done bro. Read about porting alot, but never seen it done. Wish I’d of seen the vid before I did mine. 
:thumb:
nice work dude 😉
allways good to see pics /vids of work on are beloved AF guns. 😎
even if we have seen it before.
it keeps the forum going,,,all the bits add up this is a great gun forum
with great people..
i never ever get bored on here allways lots of great threads. 😎
and i need to go top off my scuba tank down to 2500psi lol i want to start the tests at 2800psi im also testing it in a condor with a 12″ barrel so you might or might not get better results
im going to do lots of testing over the weekend and just to let you know i only have CPHP on hand in large amounts so all my test will be done with them im saving my predator polymag and beeman kokiaks for hunting
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You must have a fat o-ring. But then again I spent a lot of my time tuning down for stealth.
I had a bad year and haven’t been to the range for that long. But now I have my TT .25 AAA Condor and am getting anxious.