ATI Libert/Freedom Custom valve

[darkcharisma]

I am getting close to having fully tested these valves. this is the result of a DCTR with light valve spring to compare to the DC10A. just waiting on a bigger plenum from Billy.

DCTR specs: 2mm oem stem length, light valve spring, Billy's 15.2cc plenum.
0.255 throat, .255x.240 trench exhaust. 80gr hammer weight.

28.6grains 3.8psi fill
Fps: 880,888,998<---(3.7ksi)

26.1grains
Fps: 1034,1034,1029, 1025, 1023,1009

ending 3ksi. about 6 usable shots at 3700psi fill. the lower initial numbers are due to reg spike...its bad.


8.1cc oem plenum(-0.1 cc due to 1/8npt gauge), 3.8ksi fill, same specs.
fps: 859,908,924,962,962,962,959,956,946,938

ending 3ksi


the DCTR max at 962fps VS DC10A max at 976fps.

Hey, given all the radiuses and angles, its not much of an increase or is the DCTR falling too short behind. however, if you have Billy's 15cc plenum, you can hit 1034fps for 26.1gr AVS Slugs with the DCTR and a little more with the DC10A, i didnt test DC10A with bigger plenum because i was low on time and it does't apply to everyone.

whats next? going to push it harder combining other mods. and my metric dies are here so time to rethink about bottling one of these with bigger plenum in the breech...

[rsterne]

Those results, showing a slight edge for the valve with the proper size ports and radiused for smooth flow... compared to the valve with the trench.... are about what I would expect....

Bob

[darkcharisma]

Very minimal gains right Bob?

oh, my barrel port is angled ever so slightly towards the muzzle end. and i just added another 6fps by modding the pellet probe, so now its 968 fps with the DCTR valve.

3800psi to 3200psi, hammer weight, oem plenum, 26.1 avs slugs fps: 952,967,968,962,953

look what i just made. 416 hardened power wheels. love the color. good learning curve from making these valves. just one last test when Billys plenum gets here. gotta mod my receiver for 1/2-20 to accept it.

[cosmic]

Beautiful work Duy !! Just make time to relax !!!

[wll2506]

Very minimal gains right Bob?

oh, my barrel port is angled ever so slightly towards the muzzle end. and i just added another 6fps by modding the pellet probe, so now its 968 fps with the DCTR valve.

3800psi to 3200psi, hammer weight, oem plenum, 26.1 avs slugs fps: 952,967,968,962,953

look what i just made. 416 hardened power wheels. love the color. good learning curve from making these valves. just one last test when Billys plenum gets here. gotta mod my receiver for 1/2-20 to accept it.

Do you make the power wheels as a extra item to buy ...  would really like a few for my Liberties and my Freedom .... what size is the hole ? .. All my guns are 22 cal.

wll

[darkcharisma]

Thanks brother Ray. i shut the lathe down at 12 yesterday but i turn the mill up until 4am. 

okay, no more work past midnight.

Will, i do make those items separately. those items are time consuming to make and when i run out of 416 material i will no longer make them.
the reasons are because they require more lathe time, tap, groove for orings, mirror polish, mill for indexing slot, fit into receiver, true the receiver and end mill, mill in two steps from 3/16 to .217 final hole size, clean receiver and heat treat the wheel.
 the only part i like about it is heat treating to a patina blue...hey! sounds simple but it ain't! its hard to read the flame temp to get it exactly that color and if i didnt polish it mirror like, no colors. these wheels i made have been turning blue, brown and purple. its pretty but i want strictly ocean blue...i cant remember but i think i have to do it in two steps by polishing away the first layer of color then flame it again.

anyway, pm me i'll give ya a price. the wheel job comes with TP porting of that receiver to 3/16 or .217 so i recommend sending your receiver in.

I recommend .217

[Hawkeye51]

Hey Duy

I know you have moved on from seeking power gains on the Liberty, but I have a different question. Did you (or anyone else) come up with a mod or fix for the regulator? (eliminating spikes, jumps, creep)   Especially interested in extending consistancy at mid power levels.

Although I don't have a guage on my plenum, I do see much lower fps at a 3900psi fill than I do at 2900psi.  Regulator seems to be most consistent from 2900psi to 2200psi. at my current setting.

I would love to extend my consistancy and shot count while staying in the moderate power range.(14.6gr @ about 920-940). Does swapping the Bellevue washers help? Does polishing everything inside the regulator make a difference?  Has anyone tried different configurations on the washers?

[Madd Hatter]

I tried the McMaster Carr washers and the reg didn't like it at all. I Polished the bore of the reg but with how dang ding dong hot it's been I haven't done a shot string to see if it's helping or not yet but when I put it back together the plunger (?) that reacts to the pressure in the plenum area did seem to move easier. I also drilled out the reg vent hold 2 or 3 thousands. Not sure if the did anything but make sure it wasn't plugged from the silicone oil I lubed the washers with. It's kind of a pita that we can't fill the air tube up to it's max pressure and get consistent vel.

[USAFANG6799]

It's kind of a pita that we can't fill the air tube up to it's max pressure and get consistent vel.

Would that be because of the overal design of the regulator is not correct?
Or is it a matter of finding the right spring that goes on the poppet valve?

[Hawkeye51]

There has been so much progress with these guns in every other area, it's a shame the regulator won't function any where near the full range of the reservoir.

I don't thing the spring on the poppet valve is related, it's just the washers.

[wll2506]

Hey Duy

I know you have moved on from seeking power gains on the Liberty, but I have a different question. Did you (or anyone else) come up with a mod or fix for the regulator? (eliminating spikes, jumps, creep)   Especially interested in extending consistancy at mid power levels.

Although I don't have a gauge on my plenum, I do see much lower fps at a 3900psi fill than I do at 2900psi.  Regulator seems to be most consistent from 2900psi to 2200psi. at my current setting.

I would love to extend my consistancy and shot count while staying in the moderate power range.(14.6gr @ about 920-940). Does swapping the Bellevue washers help? Does polishing everything inside the regulator make a difference?  Has anyone tried different configurations on the washers?

Hawkeye51,

Mine is about the same, I set her on the high end at about 3200ish and go down to about 2300 at the low end .. but those are just my comfort levels, they may variety a bit in reality. I have not done any shot counts but I have not run out of air while hunting ... I'm guessing it is around 20+ ish shots maybe a bit more ?

wll

[USAFANG6799]

There has been so much progress with these guns in every other area, it's a shame the regulator won't function any where near the full range of the reservoir.

I don't thing the spring on the poppet valve is related, it's just the washers.

Robert said he tried the washers through no avail.

[Madd Hatter]

There has been so much progress with these guns in every other area, it's a shame the regulator won't function any where near the full range of the reservoir.

I don't thing the spring on the poppet valve is related, it's just the washers.

The poppet valve spring does rest against the reg plunger but doubt it affects it much if at all in comparison to 2000 to 4300 psi. Anybody happen to know what the surface area is on the end of the plunger?

[Madd Hatter]

There has been so much progress with these guns in every other area, it's a shame the regulator won't function any where near the full range of the reservoir.

I don't thing the spring on the poppet valve is related, it's just the washers.

Robert said he tried the washers through no avail.

I'm not the only one who has less than stellar results with the Mc Carr washers. Duy had problems and Wayne did also and I'm sure there's been others.

[USAFANG6799]

I'm not the only one who has less than stellar results with the Mc Carr washers. Duy had problems and Wayne did also and I'm sure there's been others.

I bought some but by the time I got them the feedback before I got to install mine were not worth the effort to install them.
Thank you Trail Blazers.

[Hawkeye51]

Maybe a different configuration with the stock washers to gain more resistancce without backing the wheel out so far?  Or maybe Bellevue washers in general aren't that precise. What do they use in a Huma reg?

[RDB]

Hey Duy

I know you have moved on from seeking power gains on the Liberty, but I have a different question. Did you (or anyone else) come up with a mod or fix for the regulator? (eliminating spikes, jumps, creep)   Especially interested in extending consistancy at mid power levels.

Although I don't have a guage on my plenum, I do see much lower fps at a 3900psi fill than I do at 2900psi.  Regulator seems to be most consistent from 2900psi to 2200psi. at my current setting.

I would love to extend my consistancy and shot count while staying in the moderate power range.(14.6gr @ about 920-940). Does swapping the Bellevue washers help? Does polishing everything inside the regulator make a difference?  Has anyone tried different configurations on the washers?

Mike, just ran some numbers for you. Don't know why Robert had problems with the bellvilles i originally posted, maybe reg pressure differences. First run with 14 crosmans 3600 psi. 881, 887,884. Bled air to 2600 psi 878, 875, 877. About 10 fps difference. Bumped reg filled to 3700 with 18 grain jsb 883, 886, 882. Bled to 2300 psi 891, 889, 897. Again, not much of a spread. Could have been coming off the reg on the last 3 shots. The McMaster car bellvilles height is taller effectively making a longer spring. But they have been working for me on tunes up to 35 fpe. Haven't went any higher.

[Hawkeye51]

Rod thanks for the response. If I could run from 3800 psi to 2200 psi with less than 20 fps difference I would be happy. Do you happen to have the Mc Masrer car # for the washers? I hate to pull the gun apart just to measure one stock washer.

If not, maybe I can look it up in one of the previous threads ( lots of reading there 😁)

Thanks

[USAFANG6799]

Mike if Rod doesn't readily have them I do.

[RDB]

Just dug em up. Pretty sure these are it.Part #96445k215.

They'll take a few hundred shots to settle in. And once you get close to your target fps, you'll have to balance your hammer strike to your reg setting to deal with some creep. But once adjusted properly my first shot is no more than 10 fps different from the rest.