ilovemyheckler Posted June 7, 2011 Report Share Posted June 7, 2011 got my new chrono to work (thanks for the advice in my other thread) but the average of 4 readings was only 6.2fps which is well below the legal maximum. Although it wasn't hot today it wasn't cold either so I suspect that this is a true average. The gun is an Air Arms S410. the reason I bought the chrono was because i suspected the power to be low. It has been recently serviced and had new seals fitted. Any suggestions how I can get the power increased? Quote Link to comment Share on other sites More sharing options...
lineshooter Posted June 7, 2011 Report Share Posted June 7, 2011 That is low,probably stuff you have already tried but, what presure did you fill to, do you know where the so called "sweet spot" is on that gun and have you tried a selection of pellet brands. Did you weigh the pellets before entering into the chrono, but saying all that I doubt if it would help you find the missing 5 ft/lb. Quote Link to comment Share on other sites More sharing options...
ilovemyheckler Posted June 7, 2011 Author Report Share Posted June 7, 2011 pressure was about 160 and i didn't weigh the pellet - i just used an average weight off interweb - not accurate but close enough to make me feel the reading was well under the maximum. For the same reason i only used one type of pellet. If i had been getting readings of 9.5 and above i would have been more accurte and weighed the pellets/tried different types etc. hat is this "sweet spot" you mention? Thanks Quote Link to comment Share on other sites More sharing options...
lineshooter Posted June 7, 2011 Report Share Posted June 7, 2011 (edited) I`m sure a technical type will be along to give a more concise answer but to keep it simple lets take my Bsa ultra as an example, the fill pressure is 200 bar if I fill to that my first few pellets are eratic in power and accuracy. If I fill to 190 bar, the sweet spot, then I know I have about 30 usable, more or less 10.5 ft/lb shots, sweet spots vary on different guns. I would recommend a set of scales if you are doing serious pellet testing, I`m not familiar with the 410 pressures but my .177 S200 sweet spot was around 180 bar, you could try again with a higher bar. Edited June 7, 2011 by lineshooter Quote Link to comment Share on other sites More sharing options...
bruno22rf Posted June 7, 2011 Report Share Posted June 7, 2011 Am I being stupid or does FPS not mean feet per second? Are you sure that the chrono is not set to give you the variation between shots? Quote Link to comment Share on other sites More sharing options...
the_commoner Posted June 7, 2011 Report Share Posted June 7, 2011 Is it the pre - anti tamper 410, if it is you may be able to simply wind the power up ? Quote Link to comment Share on other sites More sharing options...
team tractor Posted June 7, 2011 Report Share Posted June 7, 2011 S400,s only kick out 10 ftlb off the shelf but if you look at the right hand side just under the pellet tray their is a grub screw which you remove then adjust the one behind . If its a .22 then 620 fps would sound about right so just check where the decimel point is . Don't mess about if you can get the gun shop to do it Quote Link to comment Share on other sites More sharing options...
team tractor Posted June 7, 2011 Report Share Posted June 7, 2011 Also the sweet spot is 2400 PSI on your gun which you should get 40 shots but when the gauge hits 100 bar it needs filling Quote Link to comment Share on other sites More sharing options...
lineshooter Posted June 7, 2011 Report Share Posted June 7, 2011 You may be right, bruno looks like I misread, may need a setting check and I need my specs. Quote Link to comment Share on other sites More sharing options...
team tractor Posted June 7, 2011 Report Share Posted June 7, 2011 Am I being stupid or does FPS not mean feet per second? Are you sure that the chrono is not set to give you the variation between shots? Nail and head come mind Quote Link to comment Share on other sites More sharing options...
swift Posted June 8, 2011 Report Share Posted June 8, 2011 Hi there if you get stuck bring it to me I will weigh your pellets and put it over the chronograph and if the power is low I will set it near the legal limit. Quote Link to comment Share on other sites More sharing options...
Gnome of the Woods Posted June 8, 2011 Report Share Posted June 8, 2011 As a rough guide. 22 should be below 600fps And .177 about 800fps. Pellet weight for. 22 average 16grns Pellet weight for. 177 average 8.4grns If it is a crombo make sure it is the right settings. Quote Link to comment Share on other sites More sharing options...
ilovemyheckler Posted June 8, 2011 Author Report Share Posted June 8, 2011 thanks everyone. I was aware of the adjuster screw but didn't want to mess with it myself as i don't want to risk my shotgun licence if i accidentally set it above 12ft/sec swift, where are you based? Quote Link to comment Share on other sites More sharing options...
Dougy Posted June 8, 2011 Report Share Posted June 8, 2011 Dont waste your money on scales, just use the weight from the container or if no info use the internet for the av weight. Check your setting on the combo chrono it sounds possible you have fluffed up on the set up.If that is all ok then see the shop that changed the seals and tell them to sort it out Get caught with it over the limit and you can kiss any future shooting hobby goodbye, so its worth getting it done by a pro Quote Link to comment Share on other sites More sharing options...
fruitloop Posted June 8, 2011 Report Share Posted June 8, 2011 (edited) thanks everyone. I was aware of the adjuster screw but didn't want to mess with it myself as i don't want to risk my shotgun licence if i accidentally set it above 12ft/sec swift, where are you based? hi ilove the legal limit is 12ft/lbs wich is diferant from ft/sec the way you work out ft/lbs is av speed x av speed x gr of load divide by 450240 = so if yr gun av is 620fps an yr pellet is 16gr it go,s 620x620x16 devide by 450240= 13.66027ft/lbs hope this helps also dont mix gram for grane if the chrono reads fps use grane if it reads meters ps use gramms as there is a diferencs as one is metric and one is imperial but i guess you know that (did that once was there scraching my head for hours y the math was not working then looked at my scales and it had gon to gramm :o ) Edited June 8, 2011 by fruitloop Quote Link to comment Share on other sites More sharing options...
swift Posted June 8, 2011 Report Share Posted June 8, 2011 thanks everyone. I was aware of the adjuster screw but didn't want to mess with it myself as i don't want to risk my shotgun licence if i accidentally set it above 12ft/sec swift, where are you based? Hi there I'm from Derby,I must of worked on hundreds of airarms over the years had 4 round this week 2 were airarms s400 and s410 the other 2 were a daystate harrier and a brocock hunter for repair and service and power adjust close to the limit.you wont go wrong with the airarms I rate them highly. Quote Link to comment Share on other sites More sharing options...
ilovemyheckler Posted June 10, 2011 Author Report Share Posted June 10, 2011 thanks all I took it into the company who recently replaced the seals and they checked it and it was 9ft/lbs so they "tuned" it up to 11.5ft/lbs foc! Unfortunately they cannot guarantee that I will now hit everything that I shoot at Quote Link to comment Share on other sites More sharing options...
Gnome of the Woods Posted June 12, 2011 Report Share Posted June 12, 2011 Excellent result! Quote Link to comment Share on other sites More sharing options...
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