RaiderBoy 19 Posted June 17, 2009 Report Share Posted June 17, 2009 Ive been doing a little research about pellets weights and what ever and it seems that almost every pellet i have used has put me over the limit. i am reliably informed by webley that my raider 10 .22 shoots at 600 feet per second and i put this into the speed to energy converter at the theoben website here http://www.theoben.co.uk/pages.php?pageid=5 and for every pellet i have used i have taken down the results according to this pellet type grains foot pounds calculated Air Arms Field Diablo 16.00gr 12.793176972281449 Logun Penetrator 20.5gr 16.391257995735607 B S A Elite 15.43gr 12.337420042643923 Bisley Super Field 15.1gr 12.07356076759062 H and N Field Target 20.1gr 16.071428571428573 These are just the pellets that i have used so far the only ones i have found to keep me under the limit are crossman accupels and they ended up at 11.9 so next time i go to buy pellets i know which ones im buying i have no idea how to decrease the power on my air rifle and im not asking how to so ill be asking next time i am at a gunsmith so i can use my favourite pellet air arms feild diablos . I put the link up so you can test the pellets that you are using all the best Raiderboy Quote Link to post
ghillies 209 Posted June 18, 2009 Report Share Posted June 18, 2009 (edited) a couple points... did you use 600 fps for every pellet? because if your getting 600 fps with a crossman accupel a heavier pellet may well travel slower.. or faster depending on the particular gun/barrel.. and have you actualy chronograghed it? its the only way to know really. 11.5 is about the highest you want to set it at.. 11.6 if it fits to a ret patern at a push.(10.5 upwards is enough for hunting with no real advantage to 11.9... just the likely hood some pellets will go over). Edited June 18, 2009 by ghillies Quote Link to post
hughesey1552 0 Posted June 18, 2009 Report Share Posted June 18, 2009 Raider, i would of thought that if they tested your rifle they would tell you the ft/lbs rather than just 600fps as that on its own is pretty useless piece of info. Hughesey Quote Link to post
ghillies 209 Posted June 18, 2009 Report Share Posted June 18, 2009 Raider, i would of thought that if they tested your rifle they would tell you the ft/lbs rather than just 600fps as that on its own is pretty useless piece of info. Hughesey good point lol Quote Link to post
RaiderBoy 19 Posted June 18, 2009 Author Report Share Posted June 18, 2009 i got the feet per second from the webley website http://www.webley.co.uk/webley/index.php?o...&Itemid=197 and i know that all them figures are just theoretical and not all of the pellet types may have put me over the limit but i think Logun Penetrators and H and N Field Targets would certainly put me over by at least 1 foot pound. Quote Link to post
Freddy Watts 1 Posted June 18, 2009 Report Share Posted June 18, 2009 (edited) Very unlikely for it to shoot with the same fps for every pellet. Would have been 600fps for whatever pellet they tested it with but not necessarily for all pellets. If the fps on an air rifle was the same for every pellet then the light pellets would become redunadant as you would have to set it at 11.5 or so ft/lbs with the heaviest pellet possible in order not to break the legal limit. This would then mean that the lighter pellets are produceing very little power. For example for the heaviest pellet above (penetrators at 20.5gr) 11.5 ft/lbs would be at about a velocity of 502fps. The lightest pellet above (accupels at 11.9gr) would then at this velocity give only 6.7ft/lbs. So you can see from this why it is not the case that all pellets will fire with the same velocity. So to work the power you need to run each pellet over the chronograph (and if you want it exact, weigh the pellets too) Hope that makes sense. ATB Freddy Edited June 18, 2009 by Freddy Watts Quote Link to post
RaiderBoy 19 Posted June 18, 2009 Author Report Share Posted June 18, 2009 Very unlikely for it to shoot with the same fps for every pellet. Would have been 600fps for whatever pellet they tested it with but not necessarily for all pellets. If the fps on an air rifle was the same for every pellet then the light pellets would become redunadant as you would have to set it at 11.5 or so ft/lbs with the heaviest pellet possible in order not to break the legal limit. This would then mean that the lighter pellets are produceing very little power. For example for the heaviest pellet above (penetrators at 20.5gr) 11.5 ft/lbs would be at about a velocity of 502fps. The lightest pellet above (accupels at 11.9gr) would then at this velocity give only 6.7ft/lbs. So you can see from this why it is not the case that all pellets will fire with the same velocity. So to work the power you need to run each pellet over the chronograph (and if you want it exact, weigh the pellets too) Hope that makes sense. ATB Freddy cheers for that because i was starting to worry about being caught by the police with my logun penatrators going over the limit i am going to try and get hold of a decent cronograph so i can test them myself. Quote Link to post
Freddy Watts 1 Posted June 18, 2009 Report Share Posted June 18, 2009 Yeh good idea. Its best never to believe what is written in the stats on a website for an airgun (or most other things for that matter). They will just be the mean max velocity or something that they got under ideal conditions with a certain kind of pellet. So in a hunting situation especially if you don't know what pellet was used in the first place it is a pretty useless piece of information. You can get chrono's pretty cheap. Doesn't have to be a state of the art high tech million pound job. ATB Freddy Quote Link to post
hughesey1552 0 Posted June 18, 2009 Report Share Posted June 18, 2009 Not bein picky but if you only got the 600fps of the webley sight it is probably not that reliable either because, evry1 has heard storys of guns coming from the factory shooting ayt like 8 ft/lbs and having to be sent back and then other get them set perfecty. Have a look here for a chrono, seems to be the cheapest i can find...http://airgunbuyer.com/Showproducts.asp?cat=Chronographs&SubCat=Combro%20Chronographs . Hughesey Quote Link to post
ghillies 209 Posted June 18, 2009 Report Share Posted June 18, 2009 (edited) best to work from the fp's... because if the gun is pushing at say 11 foot pounds.. that gun energy cant push a heavey pellet the same as a light, so a legal gun has a few velocities... one for each weight. its a three part equation thing... to get all answers in the legal 12fp if you change a velocity you have to change a weight to give the legal limit.. if you change the weight the velocity changes (and hopefully still gives the legal limit). (not forgetting the gun can only push at one power...it afects pellets diferently for barrel fit and weight.) i.e. 2+3=5 change the 2 to a 3.. it cant = 5 unles you change the 3..... (3+3=6...)...(3+2=5) the only variable that cant change is the answer, which is the legal limit.... so a velosity is a sales gimmick.... Edited June 18, 2009 by ghillies Quote Link to post
Freddy Watts 1 Posted June 18, 2009 Report Share Posted June 18, 2009 Exactly Ghillies. Oh and cheers hughesey that was the chrono I was thinking of I just could not for the ife of me remember the name of the thing so i couldn't look it up to find a link. Hope that all helps raider boy. ATB Freddy Quote Link to post
RaiderBoy 19 Posted June 18, 2009 Author Report Share Posted June 18, 2009 Not bein picky but if you only got the 600fps of the webley sight it is probably not that reliable either because, evry1 has heard storys of guns coming from the factory shooting ayt like 8 ft/lbs and having to be sent back and then other get them set perfecty. Have a look here for a chrono, seems to be the cheapest i can find...http://airgunbuyer.com/Showproducts.asp?cat=Chronographs&SubCat=Combro%20Chronographs . Hughesey will get one of these one day because it seems its the only way to be sure Quote Link to post
ghillies 209 Posted June 18, 2009 Report Share Posted June 18, 2009 get one direct from the combro gu6y.. good chap. comes up rapidly on a google search. Quote Link to post
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