Tuning Anyone tuned a .177 DAR gen 2 to 12fpe successfully?

I adjusted the HST, but that only makes it act like it doesn't have a regulator.

Starting at 3000psi tube pressure (max fill) the first 3 or 4 shots are ~656fps then it gradually rises to ~820fps over several shots (with small plateaus occasionally) and then seems to stay about there. Even though it does seem to reach a sweet spot, that spot is a lot higher fps than I want and the pellets I am using don't like it.

I am thinking that even lowering the regulator pressure may not be enough because the hammer spring may be too strong for that regulator pressure level.

That is why I am asking for advice from someone who has already successfully tuned a DAR Gen2 .177 to 12fpe.

All I have for pellets right now are CPUM 10.5 and Piranhas. At 750fps and below they are pretty accurate in this gun, but over 750fps they scatter.

I have no experience taking apart a pressure tube to adjust an internal regulator, so ALL help in that area is greatly appreciated!

Thanks for the reply!

P.S.

Any advice on changing or modifying the existing hammer spring is also welcomed.


 
Does "Gertrude" from GTA have a presence on AGN? This person is/was involved in cleaning up the DAR GEN1 for the GEN2 version and mentioned working on adjusting a DAR Gen2 to 12 fpe. The thread is about 54 pages and I am still searching it for answers. I can't actually use the search function on GTA because I was banned (rightfully so at the time) from GTA.



Here is a link showing the internals of the Gen1 DAR .25 https://www.gatewaytoairguns.org/GTA/index.php?topic=146178.msg1490613#msg1490613

Are they the same in the Gen2? And how do I go about getting into the pressure tube?

And here is the link where "Gertrude" mentions tuning a .177 DAR Gen2 for 12fpe https://www.gatewaytoairguns.org/GTA/index.php?topic=179804.msg156041581#msg156041581

Any help is deeply appreciated!!!

Thanks,

Kerry - BackStop

BTW, I have called DAR about this problem, but I had to leave a message. I am hoping "Joe" is still working there and will be able to assist me. I like the gun, but if I can't get it to shoot consistently at 12fpe or less, it is useless to me for my pesting purposes on my property. Pass through, ricochet, etc, etc, etc are a concern for me and anything above ~12fpe is just not going to work. Not to mention that the pellets I have (CPUM 10.5) are only accurate at 750fps or less! Yeah, it would be nice if I could try JSB and H&N pellets, but they just aren't available in 10.34 as far as I can tell. I thought this gun was easy to adjust, but I guess I simply did not do my homework in much detail other than reading that it was easily adjustable, regulator and HST. My bad... heavy sigh... Live and learn... Maybe I should have taken a chance on another Nova Vista knock off...? The Freedoms DID shoot VERY accurately from 20-60 yards and I really liked the ability to basically flip a switch/knob and go from ~20fpe to ~12fpe using the same CPUM 10.5 pellets and the accuracy was GREAT at both velocities.

Oh well...

If you have read this far... many thanks! (smile)
 
I am in the process of de-tuning my .177 DAR Gen 2.



So far I have replaced the hammer spring with a lighter one that I got from my local hardware store, that I had to trim down. 



I really didn't want to crack into the air tube and void my warranty, but to get the best performance it will need to be done, because the reg is set way too high.



Mine falls off the reg at around 2000psi (14mpa).

With the lighter and shorter spring I was able to get the power down to the 14.5-15 ftlbs with 8.5 and 10.5gr pellets. And get around 70 shots on the reg before velocity starts climbing and then drops again. Hence the too high reg pressure. 



Once I get the reg set to where I want it, thus gun should get around 150 shots per fill on the reg.



I will continue to update as I go.



Hope this helps.



This is the new hammer spring that I installed.

I cut it to 1.5"



20211109_115533.1637509000.jpg



 
I am in the process of de-tuning my .177 DAR Gen 2.



So far I have replaced the hammer spring with a lighter one that I got from my local hardware store, that I had to trim down. 



I really didn't want to crack into the air tube and void my warranty, but to get the best performance it will need to be done, because the reg is set way too high.



Mine falls off the reg at around 2000psi (14mpa).

With the lighter and shorter spring I was able to get the power down to the 14.5-15 ftlbs with 8.5 and 10.5gr pellets. And get around 70 shots on the reg before velocity starts climbing and then drops again. Hence the too high reg pressure. 



Once I get the reg set to where I want it, thus gun should get around 150 shots per fill on the reg.



I will continue to update as I go.



Hope this helps.



This is the new hammer spring that I installed.

I cut it to 1.5"



20211109_115533.1637509000.jpg
//www.w3.org/2000/svg%22%20viewBox=%220%200%20210%20140%22%3E%3C/svg%3E


Thanks for the information! I still haven't voided my warranty by adjusting the reg, but as you noted, it is a necessity. I am not going to replace the hammer spring until after I adjust the reg.

Thanks again for the reply!