1. The Forum Rules have undergone some minor changes and updates.  Please take the time to read them; it will only take a couple of minutes of your time. By doing so, you lessen the chance of incurring the wrath of the moderation team or making yourself look foolish to other members.

    90% of users posting adverts in the Sales forums need to be reminded to read the rules as their posts are wrong.  This is unnecessarily time-consuming and will no longer happen - if your advert doesn't follow the Sales Rules it will be deleted and you'll have to start all over again.

    To close this box once you've read it (and the Rules), click on the X in the top right-hand corner.

    Thank you.

    AGF Staff



    Dismiss Notice
  2. A reminder of one of the Forum Rules:

    'Behaviour

    Do not make inappropriate or offensive posts - including threats, harassment, swearing, prejudice, defamation, deliberate insults or name-calling, other negative remarks about this forum, its moderators and administrators or your fellow members. Even if this is just your own personal opinion, RESPECT YOUR FELLOW MEMBERS.'

    There have been changes made to our censoring software in an attempt to help with this growing problem.

    Click the X in the top-right-hand corner to dismiss this notice.
    Dismiss Notice
  3. Dear members,

    Our membership (like our country) consists of people from all walks of life; different in far more ways than can be listed here and each with a different view based on their experience of life - regardless of their colour, religion or cultural heritage. Every single person in the UK has been born of mixed race – we are a multi-coloured and multi-cultural country.

    As many of you are aware there are a handful of individuals amongst this membership that persist in making provocative, inflammatory, racist and otherwise offensive comments. This has been happening across the forum to a certain degree but is most especially prevalent in the Adult section.

    The moderation team has tried to stay on top of this, however unfortunately because of the ‘offensive’ nature of much of its content we don’t monitor the Adult section quite as much as perhaps we should. As a result much of this behaviour has gone unnoticed unless it has been reported to us. While the team always intended to take a "light touch" approach to the Adult section it would seem that some people aren’t quite adult enough to be left unmonitored after all.

    This behaviour is, and always has been against Forum Rules as well as the specific stipulations of the Adults forum and it will no longer be tolerated. We feel it's time to draw a line in the sand and as such from this point onward offenders will receive an immediate and permanent ban from the forum.

    In order for us to achieve our goal of restoring the forum to the friendly and tolerant place it once was, we ask that ALL members be mindful of the content they post and help us to stop unacceptable behaviour by using the 'Report' tool at the bottom of any offending post - the results of which can be seen only by Admin/Moderators.

    You should all receive a copy of this message by PM. 

    To close this message box, click on the 'X' in the top-right-hand corner.

    Dismiss Notice
  4. PLEASE READ
    You are breaking the forum rules if there is no comment on a sales or wanted thread by either the buyer or seller. 
    Or regarding to members manufacturing things stating something is going to be discussed and initiated through pm.
    I.e. 
    A buyer in manufactured section hi I’m interested in some work by you pm incoming.
    Or seller in a wanted add, hi I can do that for you pm incoming regarding it.
    Or a normal sale, hi I want to buy your item
    If a manufacturer gets asked privately about a sale they should say to the prospective buyer please comment on my thread to adhere to forum rules.
    Dismiss Notice
  5. Hotmail block emails from us entering your inbox. Unless you can setup a safe sender you will not get activation emails from the forum. Please use an alternative provider or complain to Hotmail.
    Hotmail addresses include.

    @Hotmail.co.uk @Hotmail.com @outlook.com @Live.com
    Dismiss Notice

Question combro

Discussion in 'Anything Airgun Related' started by wizard1963uk, Sep 22, 2014.

  1. wizard1963uk

    wizard1963uk Donator

    Messages:
    1,916
    Likes Received:
    23
    Location:
    chatham Kent
    how do you put the exact weight of the pellet in 15.89 it seems i can only enter 15.8 do you round it up to 15.9 or leave it as 15.8 ?
     
  2. DR2501

    DR2501 Donator

    Messages:
    3,105
    Likes Received:
    15
    Location:
    Bath & NE Somerset
    I would round up personally
     
  3. sharpshooterpete

    sharpshooterpete Donator

    Messages:
    640
    Likes Received:
    0
    Location:
    Salisbury.
    Yeah i would also round it up mate.
     
  4. wizard1963uk

    wizard1963uk Donator

    Messages:
    1,916
    Likes Received:
    23
    Location:
    chatham Kent
    that's what i was thinking shame you cant enter the exact weight
     
  5. tintin

    tintin Engaging Member

    Messages:
    325
    Likes Received:
    0
    Location:
    South of Cirencester
    I know where you are coming from.
    Unfortunately someone then comes along who wants to weigh to 5 deciamal places. They are out there, believe me.
     
  6. mattyts

    mattyts Donator

    Messages:
    6,201
    Likes Received:
    167
    Location:
    Yorkshire
    Just record the FPS and use an online calculator
     
  7. terry1001

    terry1001 Major Poster

    Messages:
    9,672
    Likes Received:
    3,020
    Location:
    Ipswich
    If you round up the weight the maximum error will be 0.05 grain, in the worst case (a light .177 pellet) it would amount to about 0.07 ftlb.
     
  8. wizard1963uk

    wizard1963uk Donator

    Messages:
    1,916
    Likes Received:
    23
    Location:
    chatham Kent
    i take it that's fine then terry :up:
     
  9. mattyts

    mattyts Donator

    Messages:
    6,201
    Likes Received:
    167
    Location:
    Yorkshire
    As long as your power isn't 11.93 :p
     
  10. Dag

    Dag Pro Poster

    Messages:
    6,501
    Likes Received:
    3,589
    Location:
    Nr Leatherhead, Surrey
    You can if you go to their website. The calculate ftlbs function there allows two places of decimal.
    Dag
     
  11. wizard1963uk

    wizard1963uk Donator

    Messages:
    1,916
    Likes Received:
    23
    Location:
    chatham Kent
    ill check this out thanks dag
     
  12. busanga

    busanga Posting Addict

    Messages:
    1,618
    Likes Received:
    1,003
    Location:
    Ghana
    Also wonder why they use an old rs232 interface and not a USB. Most modern laptops don't even have that interface anymore.
     
  13. wizard1963uk

    wizard1963uk Donator

    Messages:
    1,916
    Likes Received:
    23
    Location:
    chatham Kent
    i know mate i have no idea
     
  14. terry1001

    terry1001 Major Poster

    Messages:
    9,672
    Likes Received:
    3,020
    Location:
    Ipswich
    The Combro is guaranteed to 1% accuracy on velocity and tested to 0.5%. A 0.5% error in velocity will make about 1% difference to the calculated energy, slightly more than the error due to rounding. If the figures are cumulative (added together) it would add up to about 1.5% which is roughly 0.2 ftlbs.
    Of course the 2 possible errors might just as easily cancel each other out.
    If you're concerned about this possibility you can calculate the energy using actual weights although I don't think it likely that ebay scales will actually measure to that degree of accuracy, certainly the pellets aren't made to that level of consistency.
    There's no easy way of checking the accuracy of velocity measurement. You could carry out a series of measurements using individually weighed pellets and calculate the values.
    On the other hand you could set the power to be no more than 11.75ftlb with the best performing pellet. There seems to be absolutely no point in trying to squeeze out the last tiny bit of power up to the legal limit, far better to get consistent and repeatable performance from your rifle/pellet combination to get first time hits.
    Calculations done in my head so have been rounded :D
     
    Last edited: Sep 22, 2014
  15. Dag

    Dag Pro Poster

    Messages:
    6,501
    Likes Received:
    3,589
    Location:
    Nr Leatherhead, Surrey
     
  16. Stew

    Stew Engaging Member

    Messages:
    286
    Likes Received:
    0
    Location:
    Malvern
    I have created a speed sheet where I input some pellet detail including the grain and the formula for calculating the muzzle energy, so I just use the combro to measure the velocity and type it into my spreadsheet and voila it calculates the rifles energy. I've set up the spreadsheet so I input a strong of 10 shot and it automatically shows me the Max,Min, variation and average velocity's and energy readings. This was I can keep a record of all my readings too, its a little long winded, but it works for me :)

    If I was just using the combro itself, j would just round up the grain that way your erring in the side of caution.
     
    Last edited: Sep 23, 2014
  17. Patrick

    Patrick Donator

    Messages:
    14,038
    Likes Received:
    6,854
    Location:
    Wiltshire
    Shouldn't that be 11.94 as 11.93 would make it 12fpe exactly bang on the limit but not illegal unless it went over with another pellet,not that I or anyone else would want a gun performing like that.
     
    Last edited: Sep 23, 2014
  18. Jfrwhite

    Jfrwhite Posting Addict

    Messages:
    1,733
    Likes Received:
    10
    Location:
    Carnforth
    I don't bother putting pellet weight into my combro, I just record FPS and then put it all into a spreadsheet that then calculates the power. Pretty much the same as Mattys suggestion of an online calculator
     
  19. wizard1963uk

    wizard1963uk Donator

    Messages:
    1,916
    Likes Received:
    23
    Location:
    chatham Kent
    got a pic of the spread sheet mate :)
     
  20. busanga

    busanga Posting Addict

    Messages:
    1,618
    Likes Received:
    1,003
    Location:
    Ghana
    How about a copy of that spread sheet for us less computer literate :)

    Just realized in chairgun pro under statistics you can enter string of shots in fps and it produces stats and graph. Hadn't noticed this before.
     
    Last edited: Sep 23, 2014

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice