QYS Pellets FPS

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EV2UK

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Hi all

Has anybody noticed a larger than expected drop in velocity with QYS pellets. (.177)

Doing a bit of testing at the weekend

JSB 8.44 gr - 780 fps
QYS 8.48 gr - 760 FPS

Why the drop of around 20fps with QYS, seeing as they only weigh 0.02 gr more I was expecting the same results
 
I guess it highlights the potential of going over 12 ft lb
If a rifle is set up with QYS and was near the legal limit, a different brand of pellet could push it over?
 
EV2UK said:
I guess it highlights the potential of going over 12 ft lb
If a rifle is set up with QYS and was near the legal limit, a different brand of pellet could push it over?
Click to expand...
Absolutely it could. You always want to give yourself a good amount of headroom. A nice general rule is around 11.2 ish with heavy pellets
 
EV2UK said:
Hi all

Has anybody noticed a larger than expected drop in velocity with QYS pellets. (.177)

Doing a bit of testing at the weekend

JSB 8.44 gr - 780 fps
QYS 8.48 gr - 760 FPS

Why the drop of around 20fps with QYS, seeing as they only weigh 0.02 gr more I was expecting the same results
Click to expand...
Noticed the same, was quite surprised, having said that, the change for me was 4.52 to 4.5 plus the harder pellet.
No big deal, just be aware in the wind. I am running at about 10.5.
 
EV2UK said:
Hi all

Has anybody noticed a larger than expected drop in velocity with QYS pellets. (.177)

Doing a bit of testing at the weekend

JSB 8.44 gr - 780 fps
QYS 8.48 gr - 760 FPS

Why the drop of around 20fps with QYS, seeing as they only weigh 0.02 gr more I was expecting the same results
Click to expand...
Did you weigh them? you will be suprised how out the weights are.
 
My guess is fit within the barrel. If you rod one of each pellets down the bore, QYS will have a bit more bite.
 
Its the choke when a harder lead pellet hits the choke its only in the last inch where it gets tight and thats what slows the pellet down some barrels have more choke than others.

A softer pellet deforms easier allowing it to glide through the choke more freely.
 
twigulus said:
Absolutely it could. You always want to give yourself a good amount of headroom. A nice general rule is around 11.2 ish with heavy pellets
Click to expand...
Sorry i dont agree,if a springer.
More often a spring will make power power with light pellet, so that could be over the limit.
Just my opinion
 
Buglecall said:
Sorry i dont agree,if a springer.
More often a spring will make power power with light pellet, so that could be over the limit.
Just my opinion
Click to expand...
good point - my rule of thumb above is for PCPs and should be taken with a pinch of salt. But 11.2 ish with your most efficient pellet is usually safe.
 
I’ve found it’s more the gun than the pellet fps wise, try those in another gun and you will likely get different results again🤷‍♂️
 
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