Indians For Guns

Dear members,
We(especially new airgunners) are always in a hurry to increase the power output of a given springer but doesn't understand that there is a sweet relationship between the weight and power output of a springer.
But there is no arbitrary rule as far as I know regarding it.There must be something like experience which we learn in this process.
So I request our senior members to put forward their experiences regarding it so that one who intend to tune should get a basic guidelines.
Thanks.

I put it in this way....weight is essential factor to shoot straight for a Springer.
Upto 10-11 Fpe , the weight should be 3.5 kgs+ and anything touching 15 fpe , the same weight should go upto 4 kgs +.
I also find that if the gun is little front heavy , that gives better accuracy.

Basu

Another way it all seems to work out ....(and also how you can make safe estimations while tuning) is something like this: The weight of the piston+1/2 weight of the spring should be in the range of 1/11 to 1/13 of the total weight of the AR. Being mindful of this range will help keep you do safe tweakings while tuning.

I understand most good pedigree ARs with proven performance (HW, Webley, Air Arms, etc.) stick to this formulation. Good quality Indian ARs too conform to the same equations by and large.
Regards,
Prashant

prashantjha19 wrote:Another way it all seems to work out ....(and also how you can make safe estimations while tuning) is something like this: The weight of the piston+1/2 weight of the spring should be in the range of 1/11 to 1/13 of the total weight of the AR. Being mindful of this range will help keep you do safe tweakings while tuning.

I understand most good pedigree ARs with proven performance (HW, Webley, Air Arms, etc.) stick to this formulation. Good quality Indian ARs too conform to the same equations by and large.
Regards,
Prashant

It is a great piece of information and an interesting one too.

[emoji106]


Sent from my ONEPLUS A5000 using Tapatalk

I don't think there is any relation between the total weight of the gun and the power output of that gun. The power is related to the piston weight, Spring, Piston seal and Swept volume and may be the barrel length. If you put a bull barrel it increases the gun weight but would it increase the power? The overall weight of the gun and balance to a particular shooter may determine the shootabilty of the gun to that particular person. Just my opinion.
Regards,
GNV

Dear GNV. I fully endorse your view. All parameters cited by you, are responsible for the power out put of a gun. In this context I will site a personal experiment. When I replaced gsmith 35 spring in my IHP.22 with a precihole spring, the cocking force was heavily reduced and the pellet (RWS superdome) was feebly able to den a paint can placed 10mtr away. Let me pointed out to my friends that the preciihole spring has 40 coils whereas the gsmith has 37! To make my some what straight, I am putting an image of a comparative size of the piston of a IHP National .22 and diana 350 panther .177. The pic is self explanatory.

Thank you for this illustrative update, Dear Narach93.
Can you also please tell us the overall weights of your two ARs (Diana 350 and IHP)? Also, which one of these is more hold sensitive to shoot?
By their sizes, the Diana piston appears way too light (at only 280gms) than the IHP (260gms). I am certain the Diana's SV (being a Magnum class) would be way greater than that of the IHP. Pls confirm.

Also, let me try to qualify why the PH spring was not as powerful as your G Smith in the IHP. The PH spring's rate is just 4.785 N/mm while that of G Smith 27 Spring is 5.707 N/mm. I do not know the rate of G Smith 35, but am sure it would be similar to that of Cherokee 27 (which is 7.6 N/mm). So, the PH would be no match for the G Smith 35, you see. No. of coils is just one factor (In fact, it is inversely proportional to the stiffness of the spring). If you do insist on using a softer spring like PH, then be sure to add pre-load (preferably towards the piston side, to make it heavier). This will give you both -a way higher firing cycle efficiency + higher MV + a better managed surge/piston bounce.

And, While both yours and GNV sir's points are very well taken, I think what Basu Da noted about the overall weight of the AR being a crucial factor to accuracy and shoot-ability (read smooth firing cycle and behaviour) holds 100% true. All the factors GNV sir noted (piston wt, SV, stroke, spring rate) together account for the recoil (backward jolt) and the surge (forward slam post piston bounce) that we experience while shooting an AR. Now if this recoil and surge is not commensurate with the overall weight, it will make the AR much less pleasant to shoot, either way.
I bet your Diana is way too heavier than your IHP. That weight would be to compensate for the higher SV and stroke. Again, for its power, the piston ought to be much more heavy than that of IHP (and not just 20 gms heavier). Why is it kept so light? That is yet another compensation mechanism -a lighter piston with a higher rate spring.....because a heavy piston plus a long stroke and a high SV will make for a monster which will become too cumbersome to shoot as an AR. Despite all such compensations, all Magnums remain far too hold sensitive.....That is because if they are to become as sweet to shoot as our normal ARs, they ought be made much heavier (for the power they are asked to produce). But since you will not prefer to carry that heavy a load, you have to settle with a hold sensitive gun. That is the bargain (between power and weight) that I think Basu Da was trying to point out.

Do let me know if you would want to discuss any of these in greater detail.
REgards,
Prashant

The title of this thread is relation between Power output and weight of a Springer. Not shoot-ability and accuracy.