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Thread: help me make sense of this?

  1. #16
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    Anything with an ES less than 25fps is very good.

    I don't see whats wrong with either of these loads, if they are repeatable.

    Series 1 Shots: 5
    Min 2750 Max 2772
    Avg 2765 S-D 8.8
    ES 22

    Series Shot Speed
    1 1 2767 ft/s
    1 2 2750 ft/s Group Size: 0.47 MOA
    1 3 2770 ft/s
    1 4 2772 ft/s
    1 5 2769 ft/s
    ---- ---- ---- ----


    Series 2 Shots: 5
    Min 2757 Max 2775
    Avg 2768 S-D 7.4
    ES 18

    Series Shot Speed
    2 1 2775 ft/s
    2 2 2773 ft/s
    2 3 2766 ft/s Group size 0.44 MOA
    2 4 2757 ft/s
    2 5 2773 ft/s
    ---- ---- ---- ----
    Whats wrong with a rifle grouping <1/2 MOA

  2. #17
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    Quote Originally Posted by Army-medic View Post
    The seating depth was decided as simply 10 thou from the lands of a load that up until this point seemed the best option. Thanks for enlightening me on JLK bullets; I’ve not come across them before.
    As used in the latest 1000 yard benchrest group of a little over 1" for five shots - shot from a rifle that looks like a rifle and not a piece of laboratory equipment. Used to be made right there at the competition site by Swampy Knox in his truck - J4 jackets and all, sold still hot. He WAS JLK - but sold out to another husband and wife team of national-level BR-ers.

    Here in UK it's Fox Firearms who has them -

    http://www.foxfirearmsuk.com/index.p...tom-bullets-us

    Good luck.

    tac
    Last edited by tacfoley; 14-08-2018 at 03:09 PM.

  3. #18
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    Quote Originally Posted by bullbarrel View Post
    Anything with an ES less than 25fps is very good.

    I don't see whats wrong with either of these loads, if they are repeatable.



    Whats wrong with a rifle grouping <1/2 MOA
    With factory ammo the groups were a single ragged hole.

  4. #19
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    Quote Originally Posted by Randy Bohannon View Post
    Would you like to borrow a chronograph, I’m not too far from you?
    Thanks for the offer but they published velocities were from my own magnetospeed v3, so I already have one.

  5. #20
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    Quote Originally Posted by Army-medic View Post
    Thanks for the offer but they published velocities were from my own magnetospeed v3, so I already have one.
    Aha!

    were you shooting for group at the same time as shooting for velocity?
    "An infinite number of monkeys banging away at type writers for an infinite period of time will eventually reproduce Hamlet" Thanks to discussion forums we now know this to be untrue.

  6. #21
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    Quote Originally Posted by Randy Bohannon View Post
    Aha!

    were you shooting for group at the same time as shooting for velocity?
    Yes. Do you think the chrono affected harmonics ? It’s only just occurred to me.

  7. #22
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    Quote Originally Posted by Army-medic View Post
    Yes. Do you think the chrono affected harmonics ? It’s only just occurred to me.
    If its attached to the barrel then will have some. But if it was that bad I'm sure there would be warnings about it.

  8. #23
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    Quote Originally Posted by bullbarrel View Post
    If its attached to the barrel then will have some. But if it was that bad I'm sure there would be warnings about it.
    it will have an effect but only shooting with it on / off will determine how much

  9. #24
    Randy Bohannon's Avatar
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    Quote Originally Posted by Army-medic View Post
    Yes. Do you think the chrono affected harmonics ? It’s only just occurred to me.
    Anything hanging off the barrel will affect the harmonics, for better or worse.

    several companies make barrel tuners which screw in and out to “tune” group sizes.

    i tried a magnetospeed and found it made groups open up on two of my rifles.

    given that introducing unquantifiable variables is an anathema to good reloading practice, I err on the side of caution and use a conventional chrono.

    did you shoot the factory ammo with the magnetospeed on the harrel?
    "An infinite number of monkeys banging away at type writers for an infinite period of time will eventually reproduce Hamlet" Thanks to discussion forums we now know this to be untrue.

  10. #25
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    Quote Originally Posted by Randy Bohannon View Post
    Anything hanging off the barrel will affect the harmonics, for better or worse.

    several companies make barrel tuners which screw in and out to “tune” group sizes.

    i tried a magnetospeed and found it made groups open up on two of my rifles.

    given that introducing unquantifiable variables is an anathema to good reloading practice, I err on the side of caution and use a conventional chrono.

    did you shoot the factory ammo with the magnetospeed on the harrel?
    Factory ammo was pre-magnetospeed.

    What I have concluded is that what I thought was an optimum load, probably isnt. I chronographed to see why some of the groups were poor after sticking to what I believed was a good load. I assumed it would be related to inconsistent velocities etc. It does not seem that way.

    I’m going to look at the load again and once decided upon a reliable OCW I will stick with it and just use the chrono to fine tune the load without making too much of a fuss about exact group size. Once I have chosen the load with a good velocity, low SD and ES I will check the final result without anything else added to the barrel.

    I think I may have made a bad call at the first stage and have struggled since. A morning at Bisley should resolve this once and for all!

  11. #26
    Randy Bohannon's Avatar
    Randy Bohannon is offline “Junes1 is a whining bellend”
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    FWIW I’m not a fan of the OCW method

    Maybe it shot at 300 yards plus on an utterly still day but as per the example I gave above the ifferwnces you are looking for just don’t show up at 100 yards.

    try shooting ten round groups and don’t be hasty to call fliers.

    For proper stats tats you need to shoot thirty, as you probably know.

    i would find the highest charge that doesn’t give pressure signs and then fiddle
    with seating depth to bring the groups in.

    When devloping my tatget load load for my wall varmint 308 I found that 10 round groups showed the truly consistent from the lucky.
    "An infinite number of monkeys banging away at type writers for an infinite period of time will eventually reproduce Hamlet" Thanks to discussion forums we now know this to be untrue.

  12. #27
    Parabuteo is offline My Chrony has bought it a couple of times...
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    Quote Originally Posted by Randy Bohannon View Post
    A ladder test is useful when one can’t be bothered to work up the conventional way, I think ‘medic already has and therefore it would be pointless; especially as trusting one round to show over pressure is not a very good idea.

    the node seems a grain apart from his data, he absolutely needs a chronograph if he is going to explore.
    Never used one when I shot FTR but trusted the results and the rifle. My ES was 6FPS (finally measured by 2 different magnetospeed chronos) and yes, if you attach anything to or touch a free floating barrel with anything, it will affect the harmonics. How do we thing barrel tuners work?

    With high performance rifles anything you can do that reduces the time between changes is a bonus. Dont sweat the stats, they will as likley be different between days and groups. Just get out there real time and see how they perform on paper, thinking about the marksmanship principles and consistancy. And work from there.
    I'm a maggot in another life you know

  13. #28
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    Quote Originally Posted by Parabuteo View Post
    Never used one when I shot FTR but trusted the results and the rifle. My ES was 6FPS (finally measured by 2 different magnetospeed chronos) and yes, if you attach anything to or touch a free floating barrel with anything, it will affect the harmonics. How do we thing barrel tuners work?

    With high performance rifles anything you can do that reduces the time between changes is a bonus. Dont sweat the stats, they will as likley be different between days and groups. Just get out there real time and see how they perform on paper, thinking about the marksmanship principles and consistancy. And work from there.
    Your load worked because it had a single digit ES and grouped well, a chronograph will tell you that faster than a season’s FTR shooting, surely?
    "An infinite number of monkeys banging away at type writers for an infinite period of time will eventually reproduce Hamlet" Thanks to discussion forums we now know this to be untrue.

  14. #29
    Parabuteo is offline My Chrony has bought it a couple of times...
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    Quote Originally Posted by Randy Bohannon View Post
    Your load worked because it had a single digit ES and grouped well, a chronograph will tell you that faster than a season’s FTR shooting, surely?
    It did not take a season. Nothing like. It was league FTR. Experience told me how to carry out the load dev, the chrono was pure chance when the MS came out, I tried a pair to make sure the first was not showing silly figures. Oddly I had a lot of other loads that worked too....I still do....without a chrono.

    The point is that people get tied up in apps, chronos, electronic targets, and usually end up going back to shooting at good old paper and either being happy with the results, or not.

    My only use for a chrono has been to determine whether a rifle was over the HME limit, or to get some basic data for developing wind charts. Tried a Labradar for this purpose a while back, heap!!!

    Obviously sometimes you will get issues, but often too much data fudges the picture. The next time the OP works up a load it will take less time, etc etc.
    I'm a maggot in another life you know

  15. #30
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    Quote Originally Posted by Parabuteo View Post
    It did not take a season. Nothing like. It was league FTR. Experience told me how to carry out the load dev, the chrono was pure chance when the MS came out, I tried a pair to make sure the first was not showing silly figures. Oddly I had a lot of other loads that worked too....I still do....without a chrono.

    The point is that people get tied up in apps, chronos, electronic targets, and usually end up going back to shooting at good old paper and either being happy with the results, or not.

    My only use for a chrono has been to determine whether a rifle was over the HME limit, or to get some basic data for developing wind charts. Tried a Labradar for this purpose a while back, heap!!!

    Obviously sometimes you will get issues, but often too much data fudges the picture. The next time the OP works up a load it will take less time, etc etc.
    Well yes as a folksey general point shooting at paper is the acid test but not having a chrono isn't why your load turned out to have single digit ES.

    This chap is trying to find out if his load would work at the distance required.

    A chronograph tells him that without having to shoot at that distance.

    More importantly he is contemplating going above the max load in the manual.

    A chronograph is the next best thing to a pressure lab in these circumstances.
    "An infinite number of monkeys banging away at type writers for an infinite period of time will eventually reproduce Hamlet" Thanks to discussion forums we now know this to be untrue.

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