School me on FPE

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    outdoorman
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    The velocity figures that manufacturers advertise are generally misleading as they are praying on selling to people who think higher velocity is better. They get those high figures by testing with very lightweight alloy pellets that almost nobody actually uses. The only way to know your actual velocity with the pellets you are using is to use a chrono. They don't usually advertise FPE numbers because that depends on the weight of the pellet used.

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    OldFartFarmer
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    talked to them on there "Chat"

    ,

    stock rifle/spring is not set up for a specific pellet or weight.

    the SHO Vortek kit is for a specific pellet and weight. (would not explain washers, told me only a qualified tech could set it up,,i cry foul here, I know i can take it apart and do it,

    im not a certified gunsmith, but ive worked on them for years, just now pellet rifles, but ive seen the vids, not much to it)

     

    he told me my rifle would shoot pellets from 10g – 16g  one time, then 12g-14g another time,,,,make my mind will ya?

    also cornered him on the 750FPS–told me it was a 14+g pellet,

    asked him if i shot a 15.35g pellet it would be slower,,he said yes,

    then asked if i put a SHO kit in it would i up the FPS and how many washers would i use,,,he got edgy,,we lost the link,,,go figure,

     

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    OldFartFarmer
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    so now im even more confused,

    if i shoot a certain weight pellet, and find its a hole in one,

    then do a vortek SHO spring kit, am I starting all over to find a hole in one pellet?

    how do you figure if you want to use the washers 1 or 2 or none?

     

    man, and i thought loading and shooting for groups with a 357 Magnum was driving me nuts

    this is a whole new beast to figure out,

    but maybe i can give you guys here some laughs along the way,

    as i beat my forehead on my desk,

    is there any googling to find vids on the how and why and matching up of weights?

     

    John

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    Scotchmo
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    JimNM

    FPE =. FPS*FPS*g(grains of pellet weight) / 450240

    780*780*25.4 / 450240. = 33.7  FPE

     

    Almost. Here is the corrected version:

    FPE =. FPS*FPS*g(grains of pellet weight) / 450436

    780*780*25.4 / 450436 = 34.3  FPE

    Edit: if you want to be even more precise use 2 x 225218.341 for the denominator (or 450436.682)

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    Eddie_E
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    John, I'm pretty sure the HW97K series makes 15.5 ft/lbs average in the US trim. The UK version 11.8 ft/lbs. different size and weight pellets can change those numbers by almost 1 ft/lb. Without knowing the exact pellet used in testing and the altitude and temperature, this is only an average estimate. Also the Germans rate energy in Joules, not ft/lbs as in 20 Joules and 16 Joules so we have a small conversion thing going on as well. 

    I'm one of those who thinks that FPS is meaningless by itself, but it tells me a little about the trajectory and how far it will fly flat before needing a lot of hold-over, at least within average springer energy with an average weight 16g lead pellet. (apologies to PCP slug shooters). My un-scientific gut feeling is that 830 fps is the best for bucking a cross wind and 900~920 fps is the flattest between 20~60 yards. My other wild generalization is that a springer shooting a 16g pellet over 840 fps has a horrid shot cycle and will be a scope killer and 750 fps will be smooth and accurate without trashing scopes. It's generally easier to get a .177 8g pellet to the 900fps number.

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    Scotchmo
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    MScottLeeman

    1 FPE=The energy required to move 1 pound 1 foot. And so on.

    Therefore, 12 ft/lbs equals the energy to move 12 lbs 1 ft.

    Mike

    Depending on the amount of friction, it can take almost no energy to move 1 lbm 1 foot.

    FPE would be be the kinetic energy gained by applying 1 lbf to a mass over a distance of 1 foot.

    It approximates the work (energy) needed to LIFT 1 lbm to a height of 1 foot.

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    OldFartFarmer
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    so as ive just got his rifle,

    do i shoot it with a variety of pellets? untill i find a pellet that gives me a hole in one?

    then go for a tune with that weight pellet?

     

    or do i tune then find my pellet?

     

    I dont care about fast and furious,, i shoot and load 357 and i load in the low range because it throws the lead more consistently into the "X"

    i shoot a 45-70 trapdoor original BP in competitions an yup we lob then down range, but with the right load, lobbing is consistent 

    I just want to get the cart and horse ,ducks an chickens all in the right order

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    intenseaty22
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    John. Do you own a chronograph? It’s a great tool for this sport and others. The gun’s accuracy is unlikely to be different with the Vortek. It’s also a relatively cheap part and easy to do and undo. Worth the trouble and expense (to me) if even only to find out if you like it or not. Once you do it the first time, the next twenty is no big deal. Just replace it back. 

    Depending on vendor policy, you may loose the warranty on the gun, but, it really isn’t rocket science. There’s plenty of tutorial videos out there, and plenty of folk here to guide you along the way. 

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    Eddie_E
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    intenseaty22
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    You will get different advice from different people, but the general consensus is that these guns take a tin or so to settle/brake in. 

    Some folk like to tune right away, some don’t. If/when I buy a 97 I will tune it right away with a sub 12 fpe Vortek or similar. But, that’s just me, others are very happy not touching a thing.

    yes, get a variety of pellets. The journey is fun. 

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    Eddie_E
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    OldFartFarmer

    so as ive just got his rifle,

    do i shoot it with a variety of pellets? untill i find a pellet that gives me a hole in one?

    then go for a tune with that weight pellet?

     

    or do i tune then find my pellet?

     

    I dont care about fast and furious,, i shoot and load 357 and i load in the low range because it throws the lead more consistently into the "X"

    i shoot a 45-70 trapdoor original BP in competitions an yup we lob then down range, but with the right load, lobbing is consistent 

    I just want to get the cart and horse ,ducks an chickens all in the right order

    Oh, you just wanted to know which pellet. Why didn't you say so. Try Air arms 16g and JSB 18 Diabolo and see what groups better.

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    OldFartFarmer
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    Folks complain of theres being "Twangy" im sorry i dont get it, the only noise i hear is the cast iron frying pan ringing,,

    and its a whole lot quieter than a 45-70, when i shoot 200 rounds a day for 3 days, and so much nicer on my shoulder and neck,

    and no ear-muffs required 

    I dont care about sound,

    I do want to buy a backup system to have on hand, or put in a system and keep the original for backup,

     

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    intenseaty22
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    I had a FAC stock/factory spring on my LGV, I replaced it with a Vortek 12fpe and I could tell the difference immediately. Mine went from Twang to a very subtle Thud. 

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    Windmill01
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    double post

     

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    Windmill01
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    John you mention attaining “hole in one” a couple of times from what I’ve seen in the photos of your first shots out of the box you are well and truly on your way.  

    In my own experience I haven’t done a thing to my HW77 and it’s shooting better then I can. The pellets you used to attain the above look to be doing the job but there may be another pellet your 97 likes better it’s just experimentation.

    If you want a back up kit and your happy with the current situation as intensity22 stated get a SHO Vortex or order the original factory spring and washer.

    Happy shooting

    Gary

     

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    OldFartFarmer
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    intenseaty22

    John. Do you own a chronograph? It’s a great tool for this sport and others. The gun’s accuracy is unlikely to be different with the Vortek. It’s also a relatively cheap part and easy to do and undo. Worth the trouble and expense (to me) if even only to find out if you like it or not. Once you do it the first time, the next twenty is no big deal. Just replace it back. 

    Depending on vendor policy, you may loose the warranty on the gun, but, it really isn’t rocket science. There’s plenty of tutorial videos out there, and plenty of folk here to guide you along the way. 

    Im getting a Caldwell one next month,

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    OldFartFarmer
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    intenseaty22

    You will get different advice from different people, but the general consensus is that these guns take a tin or so to settle/brake in. 

    Some folk like to tune right away, some don’t. If/when I buy a 97 I will tune it right away with a sub 12 fpe Vortek or similar. But, that’s just me, others are very happy not touching a thing.

    yes, get a variety of pellets. The journey is fun. 

    what is a sub 12fpe vortek,, is that the one SHO–without the washers?

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    DualMagMike
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    I do not think the sub 12 is a kit with no washers, I got a SHO kit and it didn't come with ANY washers. Things may have changed though, my .177 97 makes about 17fpe with no extra washers. You will need to tune first and figure a pellet after most likely as some pellets do well at higher or lower velocities BUT it MAY turn out to be the same pellet. Testing must be done and individual gun is the only thing that will answer the question

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    Brislee
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    I don't understand why you think you need to tune the gun right away?  If you are using the gun for target then yea maybe. If you are using the gun for hunting I'd say you're good to go. The more you shoot the gun the smoother it will get. The factory spring will probably go 10-20k shots. If you are happy with the shot cycle of the gun just keep shooting….it's gonna get better. If you are hunting with it, what is the distance you will shoot?  12ft.lbs will kill a squirrel @ 35 yards. If target accuracy is your thing then more than likely you ( most people ) will be more accurate with less power than you currently have. Unless you plan on shooting  at 100 yards of course. Bottom line : shoot  the gun for awhile. They are some quality pieces. Enjoy.

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    intenseaty22
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    OldFartFarmer

    intenseaty22

    You will get different advice from different people, but the general consensus is that these guns take a tin or so to settle/brake in. 

    Some folk like to tune right away, some don’t. If/when I buy a 97 I will tune it right away with a sub 12 fpe Vortek or similar. But, that’s just me, others are very happy not touching a thing.

    yes, get a variety of pellets. The journey is fun. 

    what is a sub 12fpe vortek,, is that the one SHO–without the washers?

    Here are the two kits available. Notice the washers are included. I have to double check on mine to see if in fact washers are in there. The SHO kit should yield a bit more power than the 12fpe one. Don’t quote me, but the difference may be in the spring itself: stiffness, or thickness, or length but not sure. I don’t think the difference is just the inclusion of washers or not. 

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