GTA
All Springer/NP/PCP Air Gun Discussion General => "Bob and Lloyds Workshop" => Topic started by: Earl on July 31, 2019, 12:07:34 PM
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I have a break barrel springer that I want to make LESS powerful.
If I leave it cocked, will that make the spring weaker?
I just shoot targets and I want to reduce the power and violent recoil.
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I don't think that's a reliable method of de-tuning your gun.
I would advise on getting an aftermarket spring or spring kit to achieve your goals.
What type of springer is it, and we can point you to some options?
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It will NOT make the spring weaker "Per-say" but will create a bit more SET to where the ratio of coils to free length is. In essence reduces the preload a bit if indeed the spring sags a bit and takes a set.
MANY tuners, self included use this trick to get a spring to settle down getting a better handle on output stablity and then adjust preload accordingly.
IF A NEW GUN ... No issue with cocking it and letting it sit for days. YOU WILL LOOSE POWER, but what power it ends up at generally will have a tighter ES if there are no other issues with seals etc.
JMO,
Scott
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It depends on if the spring was "set" before being installed.... If you compress a coil spring fully (until it is coil bound - all the coils touching) then basically it will never get shorter, because the steel has already been stressed to the maximum possible.... I use that on ALL hammer springs I use on PCPs, so that they never change length and hence preload in use....
Some springer tuners set their springs before initial installation, and with some springs that means they need a lot more preload on installation.... The upside is that they are fully "settled in", and at least in theory won't change after that.... If your spring is on the verge of the stress exceeding the yield strength of the steel, then it will be prone to getting shorter (and losing preload) both in use, and if left cocked for a prolonged period of time.... Some springs, it you set them, will end up so short that the gun won't perform properly, so you will have effectively "ruined" it by setting it....
So, the answer to your question is.... "it depends".... ::)
Bob
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The gun is a Winchester 1100s that I bought from Amazon for $29.
It shoots JSB 10.34 gr pellets at 816 fps now.
I have shot it about 100 times.
It is not worth buying and installing a new spring.
I would like for it to be less powerful and have less recoil.
The trigger is also hard to pull. Do you know an easy fix for that?
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It will NOT make the spring weaker "Per-say" but will create a bit more SET to where the ratio of coils to free length is. In essence reduces the preload a bit if indeed the spring sags a bit and takes a set.
MANY tuners, self included use this trick to get a spring to settle down getting a better handle on output stablity and then adjust preload accordingly.
IF A NEW GUN ... No issue with cocking it and letting it sit for days. YOU WILL LOOSE POWER, but what power it ends up at generally will have a tighter ES if there are no other issues with seals etc.
JMO,
Scott
OK, I will leave it cocked for a week or 2.
I want it to have less power and less recoil and more accuracy would be nice.
It is a $29 Winchester 1100s from Amazon.
If leaving it cocked helps this gun, I may try it on others.
Thanks
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Way back I bought a TF89 at a pawn shop. Gun kicked like a mule, rattle your teeth. Cocked it put it in a closet and forgot about it. Four months later I remembered it got it out and chroneyed it. Didn't loose one FPS.
Still kicks like a mule.
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My new Winchester 1100s had muzzle velocities with JSB 10.34 gr on 7-30-2019 as shown below.
251 m/s
249 m/s
243 m/s
254 m/s
246 m/s
This averages 248.6 m/s = 816 fps = 15.3 ft lbs
I cocked it and tied the barrel back to the stock to get maximum spring compression.
After 7 days the muzzle velocities with JSB 10.34 gr on 8-6-2019 are as shown below.
245 m/s
245 m/s
243 m/s
244 m/s
246 m/s
246 m/s
This averages 244.8 m/s = 803 fps = 14.8 ft lbs
My conclusion is that leaving the gun cocked and the barrel tied to the stock for maximum compression for 7 days
DOES decrease the muzzle velocity 13 fps and DOES make the muzzle velocity more consistent.
I do not know about the accuracy because this gun has open sights and I cannot shoot break barrels accurately.
The trigger is hard to pull and the gun kicks like a mule.
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Nice test Earl!
To the original question, my first thought was "no worse than shooting it a couple thousand times". I never did a before and after test, as I didn't own a chronograph back then, but the last 4 years or so that I was shooting the CFX it spent something like 99.85 percent of it's time sitting cocked and ready for squirrel duty and it didn't hurt it a bit more than the nearly 4000 rounds did. Literally the only time it wasn't was the few seconds between a shot and reloading it for the next shot.
The spring finally broke and only then did the velocity drop significantly. However, I only figured that out because the gun cocked differently (more grinding...) and the point of impact dropped a little. It still killed the squirrels at 20 or 25 yards too!