To Detune or Not?

I've had my Viper for a few months, now.  Some things I like and some I don't.  I'm certain the thing needs a tune as the spring twang and the torque are pretty bad.  I have found that the standard springer hold does not work.  The barrel does not return to it's original position.  It takes a small bit of pressure on the forearm to keep it under control.  The barrel is accurate when held consistently.

I'm going to do a polish/lube tune on this myself as soon as I build a spring compressor.  Yes, Charlie or one of the other guys could do a better job but I want to do it myself.

My question is whether I should consider a detune?  I don't have a chrony, but from ChairGun and measurement of targets the velocity is a little over 900 fps.  Some may debate the accuracy of ChairGun and I would probably agree.  It's close enough for my purposes, though.  What I have found is that at this time I don't need a blazing fast pellet.  Something in the 700-800 fps range with good accuracy would be fine.  I want a smooth shooter that doesn't require so much Zen to have it group well.

I haven't seen many discussions of detuning on any of the forums.  Everyone seems to want more velocity and knockdown power.  I don't recall a single recommendation on spring changes that would qualify as a detune.  I believe the Macarri and Crosman springs that seem suitable for this gun are all rated higher than the stock spring.

Any ideas, guys?  Or is this just a dumb question?

Thanks,

Rob

Rob,

I had the same problem with my Viper until I learned to support it and not hold it.  I found that I can put about 50 pellets in a one inch circle most of which could be covered with a dime in a shooting session but modifying my hold.

I sit with my knees bent toward my chest and my elbows on my knees.  I learned to do this for turkey hunting.  I lay the forearm across my cupped hand.  I only put enough pressure on the hand hold to stabilize the gun.  I do not hold the gun. I do not pull it back into my shoulder.  I slowly squeeze the trigger until I reach the end of the first stage.  Then I verify I'm still on target, take a breath, exhale about half way and fire.  I find by doing this it is rare for my sight to move.

When shooting from a bench, I allow the forearm of the gun to lay on the rest.  I stabilize the gun as above, and place my off hand (left hand for me) against my chest.  I use only enough pressure to keep the sight aligned with the target.  I can put 9 out of 10 pellets in a single shooting like this.  My viper is still factory equipped like it came out of the box. And I have yet to get 500 pellets through the gun.

Sometimes less is more!

Good Luck.
Russell

[leftcoast1]

I think the lube tune will help the spring twang. You may need custom spring guides to smooth it out. Tuna or Gene maybe able to give you some pointers or get you started in the right direction. I would leave the power as is. JMO

[vinceb]

...if it has the newer-style 2-piece tophat. Just leave the plastic spacer out, that'll reduce spring preload and bring the velocity down a bit. This might only bring the velocity down 40fps or so, but at least it might give you an idea if you're headed in the right direction.

Thanks for the help.  There's no real hurry for this as the gun does shoot well.  It's just a little trying at times.

The hold sensitivity and the twang/torque are the main issues.  I've learned to hold the gun well enough for it to shoot good groups out to 40 yards, just not consistently.  I usually get one flyer out of five shots.  It's great for pest control at less than 35 yards.  The only thing I've missed is a chipmunk.

I think a basic tune should help a great deal with the twang/torque which should improve the hold sensitivity as well.

Rob

[leftcoast1]

Rob don't for get the flyers could be the pellet its self. Deformed skirt or a balance/weight issue. It would benifit from a tune though. About 5 years ago I ran across some beeman paperwork and decided to hit their website. Got on and they were offering a lazer tune or something like that. Called them got the info sent my webley to them.. Got it back didn't notice a difference had only one gun. Now having half dozen different springers man I can tell the difference. Good luck with your self tune.

[vinceb]

What sort are you shooting?

Oh, and another thing - detuning it won't necessarily tame the spring twang. The Gamo Delta I bought is only a mid-500fps gun, but man - it sure twangs its heart out!

I'm cheating on the flyer excuse.  That's the shot I usually pull to the left.

The pellets in my preferred order:

Exacts (dead on all the time)
CPL's (a little open)
Superdomes (these group a little better than CPL's but I have to rezero my scope, they're low and left)
Hunters

JSB Predators have consistently shown better groups than the others when I test, but I only use them for pest control.  Those groups are only a little better than the Exacts.

Rob