Catweazle Posted February 15, 2012 Report Share Posted February 15, 2012 I don't want to appear difficult on this and have myself recorded better measured competitive results at 500+ than the same gun ever produced at shorter range - but never consistantly better at range, only as one offs. Its nice to think there was something special about those guns or the ammo i produced for them but in fairness i think it fluke. Thats why benchresters work on average groups. I would realy like to see a good explaination of the principles and science behind it, or even better shoot a gun that did this with certain ammo. I know some top shots who believe it and others that also think its a joke. I am just one of those who doesn't but only because nobody has ever explained it with the hard facts as to why. You would think with all the papers out there this had been done. Cyotemaster sent me a paper recently that made my head hurt, i am sure something like that exists for this? I wasn't suggesting that you are being difficult, I wrote I have no experience of this. I find it interesting because I'm a geek, so I'll have a look around and see what I can find. Who knows, maybe I'll turn up something useful. Maybe not. Maybe nobody understands it, or more likely, as with so many things, the people who do understand it aren't telling everyone. Quote Link to comment Share on other sites More sharing options...
kent Posted February 15, 2012 Report Share Posted February 15, 2012 You obviously haven't had much exposure then Kent... My Tikka T3 6.5 shooting 125gn Nosler Partitions over 40gn of Varget cloverleafs at 100 yards and is sub MOA at 200 yards... consistently... and yet, if I take the Predator 8 moderator off, the group opens up to 4" at 100 yards... yes you read right.... 4".. put the mod back on and it cloverleafs again! Last April at Bisley I was using 155gn SMKs in my TRG for the first time... we couldn't get it to group better than 2" at 100 yards (175gn SMKs will pretty much go through the same hole... consistently @ 100yds) Unfortunately, that's all I had with me so went into the club match expecting to struggle to get on paper... working on what I think is your theory, a group size of 2" @ 100 would have to open up to 12" or more at 600 yards and yet I managed 9 bulls, 8 of which were V-bulls and one flyer... The V-bull is a tad over 3". The former paragraph only shows the interaction of the moderator improves something dramatically, i should look into why that is not just accept it. I have had plenty exposure thanks, back at you i would fix that rig or sell it theres something wrong with either the gun or your hold 3 - 3 1/2 MOA improvement? i should want to know why rather than blindly except that Yes i have won best factory gun once with a PSS Remmington that i shot some tactical events with wouldn't normally hold much inside 3/4- 1 moa at 100 yds but it did it very consistant @ 500yds it did 1/2 or 1/4 cant honestly remember off a bipod! i thought it pretty neat at the time but it didn't do so well again. Its a bit like an average golfer scoring a great hole in 1 at golf, he aint gonna win next years open off it! Quote Link to comment Share on other sites More sharing options...
Vipa Posted February 15, 2012 Report Share Posted February 15, 2012 Chapter 10 of Bryan Litz's book 'Applied Ballistics For Long Range Shooting,' Bullet Stability, deals with this with all the graphs, maths and pages of hard science you could wish for! Quote Link to comment Share on other sites More sharing options...
Vipa Posted February 15, 2012 Report Share Posted February 15, 2012 The former paragraph only shows the interaction of the moderator improves something dramatically, i should look into why that is not just accept it. I have had plenty exposure thanks, back at you i would fix that rig or sell it theres something wrong with either the gun or your hold 3 - 3 1/2 MOA improvement? i should want to know why rather than blindly except that With that rifle, all I'm interested in is first shot from a cold barrel and knowing that the bullet will strike where I intend it to on the deer I have in the crosshairs.. I haven't got the time or inclination to start messing about with different loads etc.. I only ever use it in the field with the mod on so have never seen it as an issue... Only trid it a couple of times at the zero range to see what difference it would make. If it had been my TRG doing that I would have spent months and £££££ trying to sort it... alas, I don't have that issue with the TRG! Quote Link to comment Share on other sites More sharing options...
Catweazle Posted February 16, 2012 Report Share Posted February 16, 2012 5 minutes more on Google finds this article by Mr Litz; http://www.appliedballisticsllc.com/epswerve.html Very good read. It starts; This work was done to investigate a question about the grouping ability of rifles at various ranges. Many shooters, including myself, have observed the strange phenomenon of a rifle that groups angularly smaller at long range than short range. In other words, a rifle that groups 1” at 100 yards grouping 1.5” at 200 yards (you would expect no less than 2” at 200 yards). There are abundant theories about why, how, or even if this phenomenon actually happens at all. The scope of this paper is to focus in on one mechanism that’s been used to explain this phenomenon: the mechanism of epicyclic swerve. Epicyclic swerve is the technical term for the corkscrew path that a bullet flies as its nose precesses around the flight path. Some people think that epicyclic swerve explains the observed phenomenon of angularly smaller groups at longer ranges.The theory goes: “The bullet leaves the barrel with some degree of pitching and yawing motion. At short ranges, before the pitching and yawing damp out (i.e., before the bullet ‘goes to sleep’) epicyclic swerve is responsible for larger groups because the bullet is flying on a ‘corkscrew’ trajectory. After the bullet ‘goes to sleep’, the bullet flies straighter, allowing smaller groups at longer range”. His simulations seem to show that the effect, which he has personally observed, cannot be explained by the "corkscrew" effect. So far we're none the wiser. Quote Link to comment Share on other sites More sharing options...
Vipa Posted February 16, 2012 Report Share Posted February 16, 2012 5 minutes more on Google finds this article by Mr Litz; http://www.appliedballisticsllc.com/epswerve.html Very good read. It starts; His simulations seem to show that the effect, which he has personally observed, cannot be explained by the "corkscrew" effect. So far we're none the wiser. I have his book as mentioned above (autographed for me too... A fanboi I am ) It is a very good read for anyone interested in ballistics, it is long and quite often brainnumbing in it's complexity. As you would expect maths is at the core of ballistics so if you haven't got a head for theoretical maths, it may not be the read for you but Bryan does a good job of making it understandable to thickies like me..!! So... we know it happens but still don't know why, even after one of the world's foremost authorities has got his hands dirty! Well Kent, looks like your 'hard science' proof isn't going to make an appearance after all. You will just have to accept that it does happen! Alternatively you could just argue the case with Mr Litz! here's his email addy for you! bryan.litz@appliedballisticsllc.com Quote Link to comment Share on other sites More sharing options...
Catweazle Posted February 16, 2012 Report Share Posted February 16, 2012 Well Kent, looks like your 'hard science' proof isn't going to make an appearance after all. Not yet anyway. I suppose the next step would be to set up measuring devices at 50yds intervals that could record the exact path of a bullet without disturbing it, and plot these results to see what is really happening. Quote Link to comment Share on other sites More sharing options...
kent Posted February 16, 2012 Report Share Posted February 16, 2012 I notice i he mentions 1" @ 100yds turning to 1.5" at 200yds. Be fair thats one heck of a smaller improvement than some have suggested in the running of this thread (which i can handle a lot easier 1/4 of 1/60th of a degree improvement through the conical cycle of a bullets tip, as a top of the head calc, i can live with that theory) and its far,far less than the posted animation seems to suggest by its scale - note the 1 degree scale in the corner! I am going to seek out this book for my library and learn what the guy has to say on the subject, i assume he has no hidden agenda or product to push other than the search for understanding as an acedemic? Quote Link to comment Share on other sites More sharing options...
Vipa Posted February 16, 2012 Report Share Posted February 16, 2012 (edited) I notice i he mentions 1" @ 100yds turning to 1.5" at 200yds. Be fair thats one heck of a smaller improvement than some have suggested in the running of this thread (which i can handle a lot easier 1/4 of 1/60th of a degree improvement through the conical cycle of a bullets tip, as a top of the head calc, i can live with that theory) and its far,far less than the posted animation seems to suggest by its scale - note the 1 degree scale in the corner! I am going to seek out this book for my library and learn what the guy has to say on the subject, i assume he has no hidden agenda or product to push other than the search for understanding as an acedemic? He is an academic Ballastician & a world champion long range shooter but I think he either works or consults for Berger at present. IIRC I ended up ordering direct from him, worked out cheaper and I got an autograph too My personal experience was to go from a 2" group @ 100 to a 3" group at 600... go figure! Edited February 16, 2012 by Vipa Quote Link to comment Share on other sites More sharing options...
Redgum Posted February 16, 2012 Report Share Posted February 16, 2012 He is an academic Ballastician & a world champion long range shooter but I think he either works or consults for Berger at present. IIRC I ended up ordering direct from him, worked out cheaper and I got an autograph too My personal experience was to go from a 2" group @ 100 to a 3" group at 600... go figure! Very interesting reading, I have heard of the term yawing before and it all kinda makes sense, the thing that interests me Vipa is under what conditions do you get a 1" group differance between these two ranges. I'm guessing its off bags on a very still evening at a range. Quote Link to comment Share on other sites More sharing options...
Vipa Posted February 16, 2012 Report Share Posted February 16, 2012 Very interesting reading, I have heard of the term yawing before and it all kinda makes sense, the thing that interests me Vipa is under what conditions do you get a 1" group differance between these two ranges. I'm guessing its off bags on a very still evening at a range. On short siberia we were doing pre-match tweeking... I couldn't get the buggar to group less than 2" bench rested on solid bibod with rear bag. 2 other (very good) shots tried, they couldn't do any better so was resigned to performing poorly during the comp then.. managed 8 v-bulls (3"), 1 bull and one **** pilot error shot @ 600 yards!! no data for 1000 yards as I was using a borrowed scope with insufficient elevation so spent that part of the match aiming at the top of my lane number above the butts.... Texas Holdover may work in desparate civil war conflicts but it sure ain't much use on the range at over half a mile Quote Link to comment Share on other sites More sharing options...
Redgum Posted February 16, 2012 Report Share Posted February 16, 2012 On short siberia we were doing pre-match tweeking... I couldn't get the buggar to group less than 2" bench rested on solid bibod with rear bag. 2 other (very good) shots tried, they couldn't do any better so was resigned to performing poorly during the comp then.. managed 8 v-bulls (3"), 1 bull and one **** pilot error shot @ 600 yards!! no data for 1000 yards as I was using a borrowed scope with insufficient elevation so spent that part of the match aiming at the top of my lane number above the butts.... Texas Holdover may work in desparate civil war conflicts but it sure ain't much use on the range at over half a mile I have never shot at extending ranges such as these, all my rifle shooting is hunting,zeroing and playing with new loads and on most occasions dont need to shoot past 200yds. I'm quessing that these stabilising effects must happen at quite a distance as have played on paper at 200yds and found both boat tails and flat bottoms to be pretty much the same and predictable, the flat bottoms having the slight edge. How much money would you put on picking a date out of a hat, going to the range on that day and producing a 3inch group at 600yds? Quote Link to comment Share on other sites More sharing options...
Vipa Posted February 16, 2012 Report Share Posted February 16, 2012 (edited) I have never shot at extending ranges such as these, all my rifle shooting is hunting,zeroing and playing with new loads and on most occasions dont need to shoot past 200yds. I'm quessing that these stabilising effects must happen at quite a distance as have played on paper at 200yds and found both boat tails and flat bottoms to be pretty much the same and predictable, the flat bottoms having the slight edge. How much money would you put on picking a date out of a hat, going to the range on that day and producing a 3inch group at 600yds? everything in my bank account as long as it wasn't blowing a hoolie... Pheonix last year got 6 v-bulls 2 bulls and 2 just outside @ 600, results are in the public domain.. The answer to anything beyond 600 would be very different but up to and including, I feel very comfortable with and don't find overly challenging. This wouldbe as in competition, with sighters. I'm not talking about first shot being from a cold barrel Edit to say... 'Challenging' was the wrong word... I do find shooting at 600yards challenging but I don't find it intimidating... really doesn't seem that far when you are looking at the target through a decent high mag scope! Edited February 16, 2012 by Vipa Quote Link to comment Share on other sites More sharing options...
Redgum Posted February 16, 2012 Report Share Posted February 16, 2012 everything in my bank account as long as it wasn't blowing a hoolie... Pheonix last year got 6 v-bulls 2 bulls and 1 just outside @ 600, results are in the public domain.. The answer to anything beyond 600 would be very different but up to and including, I feel very comfortable with and don't find overly challenging. This wouldbe as in competition, with sighters. I'm not talking about first shot being from a cold barrel Thats pretty impressive, not that I know what a v-bull and bull size is, what scope do you use. Quote Link to comment Share on other sites More sharing options...
Vipa Posted February 16, 2012 Report Share Posted February 16, 2012 (edited) Thats pretty impressive, not that I know what a v-bull and bull size is, what scope do you use. V-bull is a shade over 3" (80mm) which is .5MOA The Bull is 1 MOA approx 6".. At 1000 the v-bull is still 14.4" but they are talking about reducing that to .5MOA (5") as F-Class shooters (not me by the way) are getting so good that many matches go to tie as 2 or more competitors 'clean' the course shooting ALL v-bulls!!! At our club comp at Bisley last year the winner (MAG357 on here) made 9/10 v-bulls and 1 flyer at 1000yards! S&B PMII 5-25x56 atop a Sako TRG .308win Edited February 16, 2012 by Vipa Quote Link to comment Share on other sites More sharing options...
kent Posted February 17, 2012 Report Share Posted February 17, 2012 everything in my bank account as long as it wasn't blowing a hoolie... Pheonix last year got 6 v-bulls 2 bulls and 2 just outside @ 600, results are in the public domain.. The answer to anything beyond 600 would be very different but up to and including, I feel very comfortable with and don't find overly challenging. This wouldbe as in competition, with sighters. I'm not talking about first shot being from a cold barrel Edit to say... 'Challenging' was the wrong word... I do find shooting at 600yards challenging but I don't find it intimidating... really doesn't seem that far when you are looking at the target through a decent high mag scope! Tell the whole tale sub .5 moa at 600 yds from two sighters aint done that much cometitively at 600 yds unless its a very good steady day on the wind. Cracking them off one after the other is easier but its still far from easy with any kit off cue Quote Link to comment Share on other sites More sharing options...
Vipa Posted February 17, 2012 Report Share Posted February 17, 2012 (edited) Tell the whole tale sub .5 moa at 600 yds from two sighters aint done that much cometitively at 600 yds unless its a very good steady day on the wind. Cracking them off one after the other is easier but its still far from easy with any kit off cue Put some punctuation in Kent... can't get your meaning from what you have posted? Did you manage to find a copy of Bryan Litz's book by the way? Edited February 17, 2012 by Vipa Quote Link to comment Share on other sites More sharing options...
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