Dual Power Quick Adjustment for Synrod Max & Target Power

The Benjamin Marauder air rifle can be tuned. You can adjust the trigger and the rifles velocities for different fill pressures.

Dual Power Quick Adjustment for Synrod Max & Target Power

Postby westgl » Mon Jan 08, 2018 12:04 pm

I bought a new synrod .22cal. and am new to PCP guns, while I Like the Marauders Power, like Most people do, I also would Like to get max shot count some times too, when shooting paper or targets, or just NOT wanting MAX penetration.

This is probably already talked to death about, But I cannot find anything specifically on what I am thinking about.

Everything I see needs to have a allen wrench/tool and no quick power adjustment.
In looking at the FX Rifles they have Power setting Adjustment thumb screw, just turn a dial and reduce power for a higher shot count providing a three power levels at the turn of a accessible adjustment screw/knob wheel, and no tools required.

This what I am looking for, a quick toolless adjustment, to take you from Max Power to target power maybe 12fpe or so

Looking at my Synrod, and it's adjustable Transfer port open/close design, this makes me think, remove the outer set screw and get a Longer bolt use the bolt head as the thumb screw adjustment, or maybe a longer set screw, long enough so that It can be used as a adjustment thumb screw, if a set screw then maybe a large diameter (maybe 3/4" dia or 1" dia) serrated nut to the end for thumb adjustment purposes.

Thinking about the Transfer ports double set screw design, one is the adjustment and the other appears to lock the adjustment screw in place. So a few choices here, I have used blue locktite many MANY times on countless fasteners, and I have used Green loctite for many applications too Green seems to allow adjustments better and still hold, I had a Motorcycle that had a ball joint swivel design that was loose and mirror would always fall to the bottom of its adjustment do to vibration, the Green Loctite took care of it one application only I could make adjustments but it would never move out of adjustment unless I moved it.

Where as blue Loctite kind of loses it ability to hold after several++ adjustments, as it is Not made for frequent adjustment holding. (Forget RED Loctite that stuff is NOT suited to anything adjustable Period it is Permanent Only)

Or Teflon tape as a thread lock.

Has anyone played with a adjustable transfer port, to go from Full Power to Max Shot
quickly without any tools?

Or is this just wishful thinking?

I under stand that shot sting and pellet arch of POI is very Important for accuracy the flatter the better.

I don't see why this could Not be accomplished using a Adjustable Transfer Port Thumb Screw.

Maybe a few markings on it or some chrony testing with it to get the right amount of turns to achieve the power wanted.

So if 4-1/2 to 5 turns out is max Open or Power, then a chrony would tell what 2-1/2 3, or 4 turns from close on the Transfer port setting.

So if I used a piece of freezer tubing for the larger transfer port for max power, I should be able to also close the transfer port with a adjustable thumb screw setting.
Synrod .22cal MFR date 06/07/17
Prod .22cal
Hammerli 850 .22cal converted 13ci 1500psi Regulated HPA
Diana 34P 350P 460 all .22cal
Hw77k .22cal
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Re: Dual Power Quick Adjustment for Synrod Max & Target Powe

Postby Denward » Tue Jan 09, 2018 3:52 am

What kind of power are you looking for when referring to max power? Either way, you'll need to adjust hammer spring preload to get max power or efficiency out of a stock rifle so tools will be needed regardless.

As for having a large transfer port tube (ie refrigerator tubing) with the valve port set to low flow, many people who have tried this report erratic velocity inconsistencies. My own testing yielded similar results.

With higher flowing valves like SS balanced valve or WAR valve and hammer debounce options like Twin spring system, you can have both power and efficiency well above what the stock gun is capable of delivering.
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Re: Dual Power Quick Adjustment for Synrod Max & Target Powe

Postby 22synrodn » Tue Jan 09, 2018 8:15 pm

That is an interesting thought with the adjustable thumbscrew though a round file on the stock edge will allow access easy enough for a hex wrench without removing the stock for the occasional adjustment. When you get down to 3 turns or less from full close, the VMS adjustment becomes more reactive.

like with the Crown, any adjustment to the tp is most likely also going to require adjustments to the hammer spring and reg to maintain a respectable tune along with scope adjustments.

You can easily hit 30 fpe with the stock tp and if you go with a larger custom tp, you can expect a larger bell curve and higher ES unless you throw in a regulator to control the peak at mid pressure.
Romans 8:1-11

22 Synrod Unregulated. Tuned using JSB 18.13gr:
30 Shots @ 31.02 FPE Avg., ES 1.36% (12 FPS), 1.58 FPE/CI

25 Synrod Regulated. Tuned using JSB MKIIs 33.95gr:
24 Shots @ 55.92 FPE Avg., ES 2.08% (18 FPS), 1.45 FPE/CI
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