Power Adjuster, SSG or Both?

[Lostcoast]

I just bought a used Discovery and want to proceed with some mods for it. I was going to purchase a Power Adjuster from DiscosRUs and then heard of the SSG debouncer thing. Does a power adjuster do the same thing? Do I need both? If both, where can I find an SSG?

Thanks,
Kevin

[Lmgunner13]

.22 or 177 discovery? I have a .22. What are you trying to accomplish with the mods? Do you have a chrony?

[Lostcoast]

It is a .22 Discovery. I will be trying to maximize power, accuracy and shot-to-shot consistency. Shot count is important but not as important as the other performance markers. I will be filling from a carbon fiber 4500 psi tank and since I have heard it is safe I plan to fill the Discovery to 2500psi or so. More, if that seems better for performance.

I do have a chrony.

[Lmgunner13]

I would run an initial chrony from 2000psi down to 1000. If you plan on fill pressures higher than recommended I would go ahead and get the high-strength screws for the valve from Magnum airpower. I bought the disco's R Us power adjuster and a couple of stock disco Springs. I also got the brass trigger and two screw modification from Baker airguns. At this point in my mods I got 24 shots at 23 fpe and 845 fps average.

It is a .22 Discovery. I will be trying to maximize power, accuracy and shot-to-shot consistency. Shot count is important but not as important as the other performance markers. I will be filling from a carbon fiber 4500 psi tank and since I have heard it is safe I plan to fill the Discovery to 2500psi or so. More, if that seems better for performance.

I do have a chrony.

[Lmgunner13]

You will need to clip a couple coils off the stock spring for the power adjuster to be effective. I also bought a stainless steel fluted hammer and stainless steel hammer pin. Then converted my disco to multi shot with a BNM multi shot breech and shroud and am waiting on delivery today of a Boyd's Gunstock to make a better fit. I can pm you my phone number if you want to talk in detail about mods.

[Lostcoast]

Thanks very much, Phil. Talking about your mods would be great. I'll be available tomorrow and thereafter. Let me know days and hours that are good to call you.

[moorepower]

Make sure you upgrade the valve screws if you plan on going over 2000 psi

[Lostcoast]

Make sure you upgrade the valve screws if you plan on going over 2000 psi

Can I get the replacement valve screws at a hardware store or is this a specialty item that I need to get from a vendor?

[KnifeMaker]

Make sure you upgrade the valve screws if you plan on going over 2000 psi

Can I get the replacement valve screws at a hardware store or is this a specialty item that I need to get from a vendor?

No Sir!  Google Magnum Air. He has is all worked out for you thru extensive test to failure. They are very high tensile strength,  And the price is very reasonable!

Knife

[Old Corps]

Do not exceed 2000psi until you get these screws. http://onlinestore.magnumairpower.com/products/discovery-valve-screw-kit

Yer welcome!

Ed

[Lmgunner13]

Definitely do the mod before attempting to fill more than 2000psi. It's worth the 10 bucks for the peace of mind and a real simple install. Just degas your disco remove the action from the stock, remove the trigger group, remove the 3 original screws and replace with the Magnum airpower screws. You don't need to over tighten them as the screws fasten to the valve. I used a little blue loctite and snugged them up. I haven't had to fill my disco past 2300 psi as that is the starting point of my flattest string. I have it tuned now to get 25 good shots from 2300 down to 1300 psi. But I think the Transfer port that comes with the BNM breech is slightly larger so that helped me get to the velocity and foot pounds of energy I wanted.

Phil

[Lostcoast]

Thanks, gentlemen - I will order the screws from Magnum Air Power today.

[Gerard]

Regarding your original question about an SSG and/or power adjuster - an SSG is like a power adjuster setup with a built-in anti-bounce device as a bonus. So yes, in part they do the same thing, but the SSG takes it further, being adjustable while also deadening the return bounce of the hammer and thus preventing re-strikes of the valve stem. If properly adjusted of course. A well designed SSG should allow adjusting the gap between its end and the hammer and the preload on the striker spring. A power adjuster only allows adjustment of spring preload.

[Lostcoast]

Is the SSG a part or assembly that I can buy somewhere, or is it easy to for me to make?

Re: Power Adjuster - is this also something I can make with hex screws and the stock spring or should I purchase an aftermarket product?

[Gerard]

Sort of one of those things where if you have to ask... you probably aren't ready to make one. Why not take a look through the SSG thread and see if it makes sense to you? It's 45 pages, but worth skimming anyway if you're interested in the device:
http://www.gatewaytoairguns.org/GTA/index.php?topic=102095.0
I don't have your particular rifle so can't comment on how easy/difficult it is to fit either an adjuster or an SSG. But loads of guys do have them, and have done either device on theirs, many mentioning results and approaches in that thread.

[Lostcoast]

Toss me into the 45 page thread instead of providing a helpful answer.. okay...

[Dead Springer]

They are not hard to make.  See photo below.  Also someone on another forum named SteveNC sells them already done.  I like the one I made better though.  The silver part is a velocity adjuster, the screw is 8-32 with knurled nuts and I used heat shrink tubing for the spring guide.  A lot of the 45 pages in the SSG thread is good reading though.  HTH

[Artie]

I too search the 45 pages for the Disco SSG. Not easy to do. Any idea what page (s) yours is discussed David? Where does the modified hose barb fit in the scheme of things, sleeved in the adjuster cap?

[c_m_shooter]

You haven't been specific enough with your goals.  The SSG will cause you to have less power, how much less depends on your setup, but will increase shot count if set up right.  Filling to higher pressure will cause you to lose power and go into valve lock unless you go deep into mods like enlarging the transfer port, porting the valve and getting a heavier hammer spring.  This will also cause you less shots per fill.  Do you have any specific energy or shot count numbers you need to hit?  You may end up ruining a rifle that is fine for what it is chasing a number that doesn't matter.

[Dead Springer]

The modified hose barb is only to adjust the internal spring retention screw.  This is how I adjust preload on the spring.  I just filed a groove into the top of the retention screw and then formed the hose barb as shown because, well that's what I had on hand and it fit.  The middle photo shows how everything is oriented inside the tube.  My process was to use the preload adjustment screw to get the velocity a little higher than my goal, then place the knurled nut on the back to fine tune into my targeted velocity and watching the shot string extend and extend.  The last post above isn't exactly right, you can adjust to have the same power as stock, but, it will extend your shot count by eliminating 'hammer bounce.'  I do believe that people using a SSG typically like the extended shot count more than the power, so they (and I) adjust to extend the shot count and not to increase power.