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Thread: What's the minimum velocity that ensures a clean hole in the target at 20x.

  1. #1
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    What's the minimum velocity that ensures a clean hole in the target at 20x.

    I shoot standing match pistol at 20 yards using flat head pellets and would appreciate a bit of info re the following : what would knowledgeable shooters recommended as being the minimum terminal velocity that would punch a clean hole in the target ?

    If it's pellet dependent, a bit more info regarding pellet choice appreciated.

    I'd appreciate this info so's I can look at maximising shot count per session, but in addition, would appreciate any comments regarding adverse effects regarding accuracy so's I can balance the outcome.

    Lastly, if you are reading this and own an LP 50, any chance your tell me the MV of your Pistol and the shot count from 200 Bar down to say 100 Bar (or alternatively a level just above where accuracy or correct pistol function would be affected).

    Thanks, Vic Thompson.
    Last edited by Vic Thompson; 05-10-2020 at 09:17 AM.

  2. #2
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    Interesting post Vic, most 10m match rifles would punch a nice clean hole at 10m with a muzzle velocity of 600fps, but that does not answer your question. I'd suggest a Crosman 766 pump, chrono at each pump, shoot at 20m on paper, and compare results?

    I've got a Rekord LP3 that runs about 250fps, I can try that at short range with wadcutters and see what it does?
    Last edited by coburn; 04-10-2020 at 06:31 PM.

  3. #3
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    The paper target will have a large effect on how clean the hole is... "proper" targets are printed on a specific type of paper and will produce a cleaner hole than normal copier paper..

  4. #4
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    Vic,

    If we assume that ca. 400 fps will produce a clean hole on a 'quality' target (e.g. McQueen NSRA targets) :

    From Chairgun, with an 8 gr. flat headed pellet, ca. 500 fps at the muzzle will give ca. 400 fps at the target at 20 yards.

    So around 500 fps as a crude estimate.

    Have fun

    Best regards

    Russ

  5. #5
    RobinC's Avatar
    RobinC is offline Awesome Shooting Coach and Author.
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    Lp50 mv

    Vic

    I'd be more interested in accuracy than MV, as long as it punches a scoreable hole and is accurate then its fine.

    My LP50e compact, with the standard, as it came Muzzle Velocity using RWS R10's shot perfectly and has won several 25 mt sport pistol British Championships, sadly not in my hands!

    Cylinder will easily last the match and sighters.

    If you are concerned,the man who will really know is Harry Preston, give him a call.

    My wife did some tests for our club last year shooting prone with her LG400 air rifle at 25 yds, the holes were very sharp.

    Have Fun
    Robin
    Walther KK500 Alutec expert special - Barnard .223 "wilde" in a Walther KK500 Alutec stock, mmm...tasty!! - Keppeler 6 mmBR with Walther grip and wood! I may be a Walther-phile?

  6. #6
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    Back in the day of NARPA shooting we used to put the targets in an oven to dry them out and then shoot them. It improved the definition and ease of scoring on them because it it made the card brittle. Why not try it?
    She was only an Admiral's daughter but her naval base was full of discharged seamen.

  7. #7
    harvey_s's Avatar
    harvey_s is offline Lost love child of David Niven and Victoria Beckham
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    At 10m I've found at anything less than 340-350 fps (muzzle velocity) some pellets can start to tumble and tear at one side of the hole.
    I wouldn't say that accuracy is badly affected - just that some holes can start to rag.
    I would guess that around 400-450 fps at the muzzle would be needed at 20m to produce a clean hole.

  8. #8
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    Quote Originally Posted by Norfolkngood View Post
    Back in the day of NARPA shooting we used to put the targets in an oven to dry them out and then shoot them. It improved the definition and ease of scoring on them because it it made the card brittle. Why not try it?
    NARPA only shot at 6 yards - but what a good introduction to the sort of target shooting with an airgun they had to offer!

    I first started target shooting with an air pistol in 1971 thanks to NARPA as they offered an inexpensive and easy to enter postal competition with an excellent "once a year" live final at RAF Cosford.

    These meetings saw the likes of many top air pistol and air rifle shooter competing against each other - many of whom went on to shoot at international level.

    Getting back to the thread - I often shot my recoilless match air pistols at 20 yards in the Exmouth Small Bore Club and outdoors on the Royal Marines range at Straight Point and the holes were sharp enough to score.

    As Robin suggests - if you are adjusting the velocity of your pistol to match your pellets - do it to get the groups tighter rather than worry about the sharpness of the cut holes. If you shoot perfectly sharply cut holes that are spaced randomly because the velocity chosen affects the accuracy of the pellet, then IMHO it would be a wasted exercise.
    Rossendale Target Shooting Club. Every Tuesday and Thursday evening 7 - 10pm.

  9. #9
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    Thanks for the useful replies to date. I'm only a plinker these days due to "the shakes" so am not too worried about accuracy to the level that most people are, but as I like to get about 200 or more shots off per visit to the range a good shot count per cylinder is useful to me. I'm currently using Hobby pellets and strangely enough they are surprisingly accurate but with the flight characteristics of a wall brick (as are apparently all flathead pellets). If I'm unlikely to get both a nicely cut hole at 20x along with a good shot count, I might as well consider using a round headed pellet with a better BC. That way according to Chairgun I can set my pistols up to get a trajectory that's ok (by my standards) for both 10 and 20x without sight adjustment with only 45fps loss in Velocity over a 20x range rather than the all but 100fps from flatheads. That way I can also reduce the MV for the same terminal velocity and save on shot count.

    Vic Thompson.
    Last edited by Vic Thompson; 07-10-2020 at 08:07 AM.

  10. #10
    RobinC's Avatar
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    Lp50 mv

    Vic

    My LP50e compact with standard velocity, punches sharp holes at 25 metres with RWS R10's and is accurate, 20 yds is significantly less, but if you want 200 shots from an LP50 you will be really struggling.

    Have Fun
    Robin
    Walther KK500 Alutec expert special - Barnard .223 "wilde" in a Walther KK500 Alutec stock, mmm...tasty!! - Keppeler 6 mmBR with Walther grip and wood! I may be a Walther-phile?

  11. #11
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    Thanks for the latest replies to my posting folks. I know that at the Muzzle my LP50 creates a clean hole in a standard NSRA supplied 20x Target but at 20x doesn't, (they are ragged and torn holes with 20xV est at MV less 100fps). When scoped and shot off the bench even Hobby pellets achieved multiple ten shot groups all cutting or lying within the ten ring. I've done this with several different pellet brands so I guess the barrel and velocity and pellet combination is ok.

    So it's ok from that perspective, but without a scoring gauge the targets are not straightforward to scope in one glance. Regarding 200 shots, that's from two cylinders and more or less achievable at present. I can weigh the full and empty cylinders and calculate start and fill pressure with an assumed capacity (as I can't find it as a published figure via the Web). Also, when I can, I'll do a few shots with match and roundhead pellets and measure MV and downrange V over a few tens of yards and see how Chairgun compares to actual measurements.

    All a waste of time for someone of my dismal standard but something that interests me just as much as the actual shooting side.

    Vic Thompson.

    ps : for a full length cylinder the 200 Bar cylinder weight compared to the cylinder weight after 100 shots indicates that the remaining pressure is 101 Bar.

    Vic T
    Last edited by Vic Thompson; 07-10-2020 at 01:59 PM.

  12. #12
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    Until the pandemic I was shooting Standard and Sport pistol comps at 25m on the turning targets at Bisley with an LP50 and R10 pellets. Scoping the holes is easy as it produces nice sharp holes, you will not get that with domed pellets. I have a full size pistol and will do a complete course of fire on one cylinder - 60 shots plus 5 sighters those that use compacts generally change their cylinders at 30 shots just to be safe. We do not crank up the output as it is not needed and seems to be far more reliable than those using real pistols to do the same thing but they do make bigger holes!

  13. #13
    tufty is offline I wondered how that worked..
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    Hi Vic,

    My LP50 cuts nice clean holes at 20yds using R10 pistol wadcutter pellets, I confess I don’t know the the MV is set at, but I can get a 60 shot standard pistol match plus sighters out of one cylinder, when the club reopens in December you are welcome to check the MV of my pistol if that would help.

    Neale
    Steyr LG110 Hunter,AA410 in Gary Cane stock,HC, Steyr LP50,Morini 164ei,Morini CM84e,Anschutz 1417 thumbhole,Rimfire Magic 10/22,Anschutz 1913,Rieder and Lenz Z2,Keppeler 6mmbr

  14. #14
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    Thanks for al of the input everyone, and especially Neale who I'd like to take up on his offer of comparing his pistol against mine as regards MV, target appearance and shot count.

    Vic Thompson.

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