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aircube · Veteran Member

Heres a general question about pellets and rifles:

If i am using a std weight pellet like a CP hollow 14.3 gr in .22 and i'm averaging 480fps, if I go to a lighter pellet like a 12 gr silver bear or a raptor and only get a few more fps like 495 fps

...does this mean the tranfer port is limiting the speed of the lighter pellet. I would have guessed the lighter pellets would be 10-25 % faster. Question

Amigo · Veteran Member

aircube:

I would not respond with an absolute no, but would consider it unlikely. If there is enough of a pressure jet (air) to propel a heavy pellet wouldn't there be a sufficient amount for a lighter one?

If the lighter pellet has a smaller diameter skirt or a thinner more easily "swagged" skirt, less pressure would build in the compression chamber before the pellet escaped its "seat" position at the breech.

This is one of the reasons why a particular airgun "likes" some pellets better than others.

You have given so few details and there are also so many variables that a complete analysis can't be made, but the general principle above is the more likely.

Amigo

rsterne · Moderator

You didn't state if your airgun is a springer, CO2, or pneumatic.... but in the latter two, I find the energy to be a bit higher, generally, with heavier pellets.... Even if it were the same, with the weights you compared, you would only expect about a 9% difference in velocity (energy is velocity squared times weight).... so not unusual to find less than a 10% difference in velocity between those pellet weights....

Bob

Buster Bodine · Veteran Member

My first question would have to be, where are you getting this velocity data?

aircube · Veteran Member

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