Chrono Results for 2240 Valve Extension and 1377 Valve Stem Exhuast Valve

Chrono Results for 2240 Valve Extension and 1377 Valve Stem Exhuast Valve

Joined: January 28th, 2004, 8:28 pm

June 22nd, 2012, 2:58 am #1

Here is my latest chrono results. The first string is a stock valve with a slightly ground down stock poppet head and the piercing pin removed, stock hammer spring, and stock valve spring. No other mods done to this valve at this point other than the Protop and the Valve Extension installed.

The breech is Cothran Machine with hollow bolt. Gun has a 12 inch barrel. Velocity Adjuster was unscrewed all the way, so no extra tension on the spring. Also used one of Anthony's Protops to test the gun with 12 gram cartridges.


Here is my original string when I started modifying this valve with 12 grams.......

Temp 68 degrees using co2 12 gram
14.66 grain Beeman FTS domed
CED Millennium Chronograph

535
529
530
540
533
533
529
530
523
525
525
525
523
520
515
506



Then I rebuilt the valve a little. It was modified with a 1377 valve stem installed and the main exhaust port reamed out to .243. It now has a 1377 valve stem, stock weight valve spring, and stock weight hammer spring. Exhaust valve is drilled out a little but there is no other mods, porting or polishing.

Temp 60 (too cold!!!) degrees using co2 12 gram
14.66 grain Beeman FTS domed
CED Millennium Chronograph

542
543
541
535
533
539
526
528
532

I got tired of waiting for the weather to warm up, so I installed my 2240 Powermax HiPac on the gun (being as the valve extension is 1 5/8 longer, the difference between a 2240 and 2250 tube), and these are the numbers that I got off of 1250 PSI:

No tension on Vel Adjuster Half Tension Full Tension
630 649 646
654 635 615
642 607 586
629 582 550
617 560 500
596 517 449
574 477 398
553 423 empty
532 386 empty
485 331 empty

I also filled it to 1300 and got my first shot at 660. Mind you this is a stock hammer, hammer spring, and valve spring. I had a half a turn on the velocity adjuster for that shot.


Last edited by sonargodz on June 22nd, 2012, 7:01 pm, edited 1 time in total.
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Joined: January 28th, 2004, 8:28 pm

June 22nd, 2012, 7:03 pm #2

Photo of the 2240 valve extension prototype with one of Antony's Protops installed. The finished product will be made out of silicon bronze or steel.



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Joined: January 28th, 2004, 8:28 pm

June 22nd, 2012, 7:07 pm #3

Here is my latest chrono results. The first string is a stock valve with a slightly ground down stock poppet head and the piercing pin removed, stock hammer spring, and stock valve spring. No other mods done to this valve at this point other than the Protop and the Valve Extension installed.

The breech is Cothran Machine with hollow bolt. Gun has a 12 inch barrel. Velocity Adjuster was unscrewed all the way, so no extra tension on the spring. Also used one of Anthony's Protops to test the gun with 12 gram cartridges.


Here is my original string when I started modifying this valve with 12 grams.......

Temp 68 degrees using co2 12 gram
14.66 grain Beeman FTS domed
CED Millennium Chronograph

535
529
530
540
533
533
529
530
523
525
525
525
523
520
515
506



Then I rebuilt the valve a little. It was modified with a 1377 valve stem installed and the main exhaust port reamed out to .243. It now has a 1377 valve stem, stock weight valve spring, and stock weight hammer spring. Exhaust valve is drilled out a little but there is no other mods, porting or polishing.

Temp 60 (too cold!!!) degrees using co2 12 gram
14.66 grain Beeman FTS domed
CED Millennium Chronograph

542
543
541
535
533
539
526
528
532

I got tired of waiting for the weather to warm up, so I installed my 2240 Powermax HiPac on the gun (being as the valve extension is 1 5/8 longer, the difference between a 2240 and 2250 tube), and these are the numbers that I got off of 1250 PSI:

No tension on Vel Adjuster Half Tension Full Tension
630 649 646
654 635 615
642 607 586
629 582 550
617 560 500
596 517 449
574 477 398
553 423 empty
532 386 empty
485 331 empty

I also filled it to 1300 and got my first shot at 660. Mind you this is a stock hammer, hammer spring, and valve spring. I had a half a turn on the velocity adjuster for that shot.

Here you go in case you are interested. They flow alot more at higher pressures because of the reduced diameter of the stem and the poppet.


Here are a couple of photos of the valve with the 1377 stem installed:





If you are interested in the 1377 stemmed 2240 exhaust valve, it comes with a stem and the front half of the valve, shipped US Mail for $25. Antony's Pro-Top is not included........

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Joined: December 14th, 2010, 5:08 am

June 23rd, 2012, 6:37 pm #4

...
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Joined: January 28th, 2004, 8:28 pm

June 24th, 2012, 7:25 am #5

I sell them for $35 shipped us mail if you want. Email me and I will respond ASAP.
My test gun is having issues with a bad pump cup. I wish I had some good numbers for you, but the valve does definitely wake up with the smaller poppet and stem. I also bore it out on the main exhaust port too.

I will post pictures soon. Photobucket and my iPhone hate each other. Email me at sonargodz @ hotmail.com if you want pics or more details after you remove the spaces from my address.
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