I've always liked the way well worn in airguns feel when fired. They don't need to be right at factory specs to be nice shooters. Some of the sweetest airguns were shot enough that their springs must've start to sag just a smidge. Enough to take the harshness out of the shooting cycle so to speak.
So naturally I started wondering what it would be like to have a slightly lower powered tune for some of these big Dianas. Da heck wit' da power tunes, how about some real sweetness in a smooth shot cycle.
Would a 3fpe lower powered 48 for example be a Lot smoother, or just a little smoother? Would the difference have to still be more fpe? I ask because the more still the rifle is on the fired shot the more accurate the shooter can be.
Am I the only guy here who thinks a lower powered tune might enhance accuracy? Am I wrong? On the right track?
Hi Harv, I am right behind you on the idea, I have been working on the idea of a model 34 turned into a somewhat target type gun because they are a reasonable priced gun, if you took a magnum springer and take off a few fpe I am shure it would be a totally different gun. I have also checked around about doing stuff like this without spending too much money as I am in the expirimental stage of all this, some of the Titan mainsprings will do it, however untill I plunk down some money order some of this stuff up won't know what all is involved in all of it yet here.
wasn't too concerned about gaining any fpe . If I'd had the choice of the GSI - I would have went that route .I saw some posts referring to using fwb124 springs or cut down/top hatted/spaced GSI springs as the ticket to the 10-12 fpe range for the 48 . Might be the way to look?
So when this 40 gets around to arriving ,something in a detune "may" interest me . I want to put some lead downrange with it before deciding . From most accounts I've heard and read, it is very well liked as is .
Harvey, I have tuned RWS54's and RWS350s down as low as 10fpe,
December 21 2007, 7:31 AM
the 54 is ridiculously "smooth", smooth as an FWB300s with zero perceived recoil...the 350 on the other hand is smooth but there is the gentle surge of big heavy piston's momentum traveling to the end of the compression tube and stopping....bug busting accurate though and silly simple to cock...think of an R7 sized for a mountain man!!!
I went with the GRT kit and apex seal. I don't have a chrony. Shooting the gun after the tune would give you the impression that it has less power. The gun is smoother and much easier to cock. The gun used to torque a lot, especially with lighter pellets. Now with my standard weight pellets there is no torque. The gun seems a lot quieter. Scope creep is no longer a problem.
Judging from the one hunting shot so far, and how fast the pellet seems to hit the target at 40 yards, I would say I have a bit more power.
I guess my point is that a good tune might let you have your cake and eat it too.
Re: Tony any issues with piston bounce with that ?
December 21 2007, 8:26 AM
Do you guys feel you're much more accurate with the rifles detuned? That's the thing I'm driving at. to reach that point where just enough energy is created where the rifle is left near still.
Like Tony's 54 but maybe with a little more... juice.
you are talking about (kR) is an idea from Ed k the tuner. I e-mailed him and waiting for options. If you want 10-12 fpe on your gun.
You are basically reducing spring tension which gives you a smooth shooting experience w/GSI kit. Less vibration and recoil and yes less fps.
GRT with a complete tune gives you the same as shooting 1.000 - 1,500 pellets through your gun, with the benefit of disasembling the power plant and making sure you have tight tolerances.
and remember "it's 30% the gun and 70% the shooter"
As I understand with a mod that reduces # of coil springs is that the tension is less to move the piston. The air in the chamber stays the same but the spring having less coils produce less recoil on the 2nd bounce of the piston, not the forward but the return action.
Less power on the spring gives less recoil.
warren
and remember "it's 30% the gun and 70% the shooter"
at 1k-1.5k through it ...I'm almost there already ! With no "work" involved LOL .Funny this thread took off as I recieved my kit this a.m. -I'm thinking of just holding off a bit longer to see *if* it settles down a lil bit more . It surely is pretty nice now. If it isn't needed ...I just have spares !
I searched around more and found that Tony used the GSI (and alot of cutting coil by coil) . The fwb124 spring is the one that was having piston bounce tuning issues.Basically involved getting the spacer height correct .
Harvey, I believe all magnum/super magnum springers
December 21 2007, 8:49 PM
benefit from lowering the power down and tuning them to achieve the best and most consistent accuracy. Another issue to contend with is the "horsepower to weight ratio"...
Think about the guys that compete at FT with their full blown TX200MKIII's with the power turned down to 12fpe or less and sitting in a massive FT stock...total rig weight over 15lbs...why do they do it? Certainly ergonomics is a factory but the other reason is to make that gun as stable/motionless and consistently accurate as possible...mainting follow through on the sight picture isn't a task easily done on a 32FPE Webley Patriot/Beeman Kodiak(.25) that's weighing 9lbs.(at least it isn't for me with the 2 that I have owned)...
BTW, that took a bit of fiddling on the 54 to get that power down that low....the kit you would want Harvey, seeing as you want a little more oomph is a V-Mach Tune Kit, go with the U.K. Spec. 12fpe version...these kits come with washers to space up if you need a little more...other wise, go with the FAC version or JM's GRT Kit as that should settle down at 14fpe or so IIRC once its settled in...