Previous

Trajectory

Viewing 20 posts - 1 through 20 (of 25 total)
  • Views : 374
  • Link
    Profile photo of SoldSpartan
    SoldSpartan
    Participant
    Member

    Forget foot pounds; what has a flatter trajectory .177 or .22?

    Link
    Profile photo of Mousefart
    Mousefart
    Participant
    Member

    More info probably needed, like what grain weight and FPS for each caliber.

    All things equal though (they usually aren’t) it depends upon the distance, I think. Shorter distances favors smaller calibers and longer distances favor larger calibers. That’s only a very general rule of thumb though, easily violated in any number of specific examples. 

    Bottom line, again, is that it depends. 

    Link
    Profile photo of JimNM
    JimNM
    Participant
    Member

    My fail

    • This reply was modified 2 months ago by JimNM.
    Link
    Profile photo of Mousefart
    Mousefart
    Participant
    Member

    “JimNM”Faster pellet is “flatter” shooting.  Caliber has nothing to do with it.  Slow .177 will droop just like a slow .22.  FPE is derived from weight*velocity*velocity/420450 (from memory…it may be 450420…?)

    FPE is not dependent on caliber at all.   Weight and velocity.

    
Sorry Jim, but saying that caliber has absolutely nothing to do with it simply not true as a blanket statement. Ditto your seeming assertion that the only relevant factor is FPE . I ask with all due humility and respect that you PLEASE do some research before leading the OP or other readers astray. 

    OP, research “ballistic coefficient” for a taste of the complexities involved here. It will take a while but you just might have fun geeking our on the topic since you’re asking the question to start with. 

     

    • This reply was modified 2 months ago by Mousefart.
    Link
    Profile photo of JimNM
    JimNM
    Participant
    Member

    My fail.  No insult intended.

    • This reply was modified 2 months ago by JimNM.
    Link
    Profile photo of JimNM
    JimNM
    Participant
    Member

    As an aide, what is the  absolute difference in BC between say a CPHP .177 and a CPHP in .22?

    Base solely on my ignorance, I would put it dang close ” negligible” if even measurable beyond  the theoretical.

    Link
    Profile photo of thwakkk
    thwakkk
    Participant
    Member

    I have to agree with Mousefart regarding more information is needed. If you would download Chairgun Pro from the Hawke optics site and get to know it you can play with all kinds of inquires regarding trajectory as well a many other factors (like FPE).

    Input the proper information and you will see what you can expect from your preferred airgun(s). Some inputs such as scope height can be tricky to find but some searching on the internet can provide several methods. I am a big believer in this program and like to have a realistic expectation of what my gun can do in the field before I go out. Factors such as wind can play with the actual results in the field but overall Chairgun will provide all the info you need to start with.

    Part of the journey in the airgun hobby is learning so enjoy the trip….

    Link
    Profile photo of JimNM
    JimNM
    Participant
    Member

    My fail.

    • This reply was modified 2 months ago by JimNM.
    Link
    Profile photo of Mousefart
    Mousefart
    Participant
    Member

    “JimNM”The constant of gravity is constant.  Physics 101.  Every object will fall at the same rate.

    The OP is intimidated by theory and numbers.  In his frame of reference, the question is unanswerable.  The OP wants to discard talk of FPE, and thereby also eject velocity from the discussion… To arrive at a simple answer to an unaswerable question.

    Which caliber is flatter shooting?  Neither.  The constant of gravity is constant.  Caliber does not determine acceleration.

    What is the BC of a .177 pellet vs. the same pellet in .22?  I don’t know…please inform me.  Is there a realistic difference in the under 30 yard performance?  How much will the OP be aware of without laboratory tools and techniques?  I doubt the OP could tell the difference with all other things being equal.  Ergo, I strongly feel that he is barking up the wrong tree.  Caliber by itself does not make the trajectory.

     

    Oh please. 
The OP being a newb is no excuse for feeding him or any others reading this thread bad info, as you’ve done. 

    Doubling down on said bad info under the auspices of a newb being too new to handle or even be introduced to a BC discussion is an insult. If he’s bright enough to ask, he’s bright enough to be told the truth, and not some dumbed-down, demonstrably false, “babies come from storks” narrative. 

    At the the very least, don’t make false blanket statements as if they are fact, and don’t treat your fellow hobbyists as if they’re not up to your mental standards. People come here to learn and not to be talked down to. 

    • This reply was modified 2 months ago by Mousefart.
    Link
    Profile photo of JimNM
    JimNM
    Participant
    Member

    Ok.  I have failed to be understood.  My bad.  I will edit out the offending parts.

    Caliber by itself does not hold any meaning to trajectory.  

    Link
    Profile photo of SoldSpartan
    SoldSpartan
    Participant
    Member

    I’m asking this because I’m worried how far can a pellet go and still hurt someone.

    Link
    Profile photo of SoldSpartan
    SoldSpartan
    Participant
    Member

    I’ve got about 700 to 750 meters from my house to the interstate.

    Link
    Profile photo of Mousefart
    Mousefart
    Participant
    Member

    The data I have seen for my .25 cal, 34g, 760 FPS pellet indicates that the farthest it can go, even when fired on a 45 degree up line, is approx 600 yds. At that point it’s falling nearly straight down and virtually harmless. If it fell on your head it wouldn’t even mess up your hair. I do say “virtually” with some caution though, and to be safe would consider anything within that radius a “kill zone”. 

    Link
    Profile photo of SoldSpartan
    SoldSpartan
    Participant
    Member

    So what is the range where a pellet of an air rifle in .22 cal go before it can hurt someone?

    Link
    Profile photo of Goodtogo
    Goodtogo
    Participant
    Member

    I think one of these charts will cover the .22 pellet range if you don’t want to download one of the programs that cover that?

    https://www.bing.com/images/search?q=.22+cal+pellet+trajectory+chart&qpvt=.22+cal+pellet+trajectory+chart&qpvt=.22+cal+pellet+trajectory+chart&qpvt=.22+cal+pellet+trajectory+chart&FORM=IGRE

    Link
    Profile photo of Mousefart
    Mousefart
    Participant
    Member

    “SoldSpartan”So what is the range where a pellet of an air rifle in .22 cal go before it can hurt someone?

    
Ok, I did some digging for you. A fairly hot .22 firing one of the heavier .22 pellets degrades to the muzzle energy of a fairly hot airsoft gun by about 450 yards. An airsoft isn’t gonna hurt you unless you get hit in the eye, so I would apply some fudge factor there for safety’s sake and say that 600 yards is the extreme range of your .22, and that anyone inside that is vulnerable unless wearing eye protection. 

    Link
    Profile photo of sharroff
    sharroff
    Participant
    Member

    I setup chairgun Toolbox app for a .22 JSB 18gr fired at 935fps (my MCT’s velocity) for max distance and got a max range of 596 yards when fired at 22 degrees.  Peak flight is 464 ft up and the pellet will be flying for about 10.33 seconds before landing at about 133 ft/sec with about 1 ft/lb of energy.  

    Link
    Profile photo of Mousefart
    Mousefart
    Participant
    Member

    Interesting. I calculated under 425 yds for an 18g. What BC and drag law did you use, if you don’t mind my asking?

    Link
    Profile photo of sharroff
    sharroff
    Participant
    Member

    Defaults for the JSB 18s

    Link
    Profile photo of Mousefart
    Mousefart
    Participant
    Member

    Cool. Good work, thanks!
     

Viewing 20 posts - 1 through 20 (of 25 total)

You must be logged in to reply to this topic.