foxpig Posted December 8, 2015 Author Report Share Posted December 8, 2015 Don't think your overdoing it at all George.its all great help. Process of elimination. You've said something that could be a cause. I didn't think it was an overly hot load but it may be . 6.5x284 123gr amax 53.3gr n560 26inch barrel. 3190fps Es 11fps Link to comment Share on other sites More sharing options...
gbal Posted December 9, 2015 Report Share Posted December 9, 2015 IF virgin brass shoots superbly,then that same brass has fliers when reloaded with no changes,something seems likely to have changed from Virgin loaded to second loading firing,and is consistently related to the loading/firing.....ie it's like barrel heating,an earlier thought,but not eg a loose screws in rifle/scope issue. Is stretching of the case neck a possible.....I don't know if the load is hot as I don't shoot that cartridge,but a case neck stretch between first and second firing would give more dispersed shots...though you'd expect some chambering issues too-maybe the brass is right on the limit....just chambers,but isn't too happy... ...easy to check,just measure virgin and the once fired brass .Or twice fired-if any,as said earlier,firing the flier brass again ,you might expect fliers again....if not,then something more complex is at work... Let's see if case neck stretching has occured enough to compromise precision....( easy check,easy cure-trim.) g Link to comment Share on other sites More sharing options...
Brillo Posted December 9, 2015 Report Share Posted December 9, 2015 Is this problem happening after each batch of fired virgin brass or has this just happened? If it's only just happened then it could be something that's changed since the first firing. If this happens after every outing with the second firing then it points to the brass. I hope I've explained that OK. It makes sense to me but........... Link to comment Share on other sites More sharing options...
simonl Posted December 9, 2015 Report Share Posted December 9, 2015 I'm not understanding something here - why is there no questioning of the chambering? Given that it's only FL not Neck sizing, isn't that a (potentially large) variable? Link to comment Share on other sites More sharing options...
gbal Posted December 9, 2015 Report Share Posted December 9, 2015 RE chamber-well it might yet be,but foxpig had confidence in the smithing,and virgin brass firing was 'superb'....if you question the chamber,how do you answer that question....the rifle will have to go to the smith-that may be inconvenient at the moment,but it may need doing..... there are other possibilities-as in once fired brass changing somehow,why I suggested stretched necks- it's really easy to check that,and eliminate.just measure them! I assume the brass has been neck sized only with Wilson dies.,not FL,Simonl but needs confirmation. Meanwhile, measuring the fired brass is easy,quick and might be informative-it's essentially a process of elimination,but done i some kind of order that minimises cost etc....I'd still like to know what happens if the now twice fired,second time fliers brass is loaded and fired again...if there are no fliers,that is informative,but just of what I doon't see at the moment. Random inch fliers suggest something pretty major...in a precision rifle-and remember it shoots superbly,virgin brass ...which then goes fliers....no other change... Brillo,I did ask if this was a decent sample,or "just" 3-5 shots,first then second firing....as you say,important to see if there is consistency-and as I said ages ago,it rather rules our random inconsistencies (in the brass) if it is consistent-can't be just reloading defective brass,after (how many?) superb shots first...then it all goes off on second loading.... Sometimes it's what doesn't happen that gives the clue-as Holmes said,the dog didn't bark in the night-and that was the strange thing (because it should have...so there was no intruder). g Link to comment Share on other sites More sharing options...
foxpig Posted December 13, 2015 Author Report Share Posted December 13, 2015 Ok so some measurements have been made. Headspace New lapua brass . 1.8005 Once fired . 1.8055 - 1.8035 Could this be causing the issues. My headspace gauge was faulty and this is with a new gauge from spud. Link to comment Share on other sites More sharing options...
simonl Posted December 13, 2015 Report Share Posted December 13, 2015 I might have been lucky enough to have guessed this, but I've nowhere near enough experience to know how much difference it might make. What are your options? 1. Develop new load for chamber sized fired brass lightly bumped back 1 thou? 2. Keep using new Lapua brass (and send me the once fired cases!)? 3. FL size back to as new? I pose them as questions because I generally know what I don't know. Link to comment Share on other sites More sharing options...
gbal Posted December 14, 2015 Report Share Posted December 14, 2015 Simonl,you did very well to keep your guess well hidden in a general 'measure the brass' ( :-) though that is a most sensible -indeed almost neccessary one,when something isn't right. I am not at all sure we have collectively nailed the cause-and ,like you I am ignorant of go/nogo or indeed any headspace measures in this cartridge. I suggested neck stretch migh have occured much faster than normal-though I don't know if the load given is hot-but again I can't decide on that from the headspace data alone,in an unfamiliar cartridge,not known for excess stretch (unlike the Swift,eg) Bumping back the shoulder might help/work. If it is excess neck length,the standard remedy is to trim the excess necks back to spec. The brass might well be unsatisfactory in your rifle too....,especially if your custom chamber was cut with the same reamer,and if it was not,perhaps not........... more :-) I'm sure someone will be along soon to sort out the headspace/neck stretch issue. It's been a puzzle...still is,dear Watson. gbal Link to comment Share on other sites More sharing options...
foxpig Posted December 28, 2015 Author Report Share Posted December 28, 2015 Finally got a day with a wind below 20mph today. Here's a pic of new Virgin brass on left 4 shot group at 150y. On the right is the 2nd firing bumped back brass to mimic new brass dimensions. As you can see the group has done exactly what it was before . So no improvement at all. And what was more worrying was the signs of pressure on the brass. With the ejector clearly showing on the rim and a stiff eject. I suppose my options are carry on buying new stuff. Or work another load with a new bullet weight and see if this will work.. Link to comment Share on other sites More sharing options...
gbal Posted December 28, 2015 Report Share Posted December 28, 2015 Foxpig,Sorry there is still the same issue.....just to be sure on each pointby point: OK shoulder bumped,and 'as new dimensions"-All Sensible-did that include trimming the brass back to recommended OAL ,or a tad less? And did the chambering get checked,as some recommended?-even with cartridges rechambered in the same orientation....won't fix exactly,but might just diagnose a chamber isssue if they then shoot ok/better han in random orientation...has the smith checked it all? It is shooting very well with the new brass-so bullets seem well suited-I suppose another make of brass is a possible thing to try.... gbal Link to comment Share on other sites More sharing options...
foxpig Posted December 28, 2015 Author Report Share Posted December 28, 2015 Yes gbal. I have done everything I can to clone Virgin brass. On the calipers they are identical apart from they have been fired once before.i even did a batch with a slightly clean up on the neck Turner to make the shoulder angle as sharp as the new ones. That group was even worse. This is with 123gr amax. Next week I'll try some 140amax and hope and pray that they will fire more than once. I really don't want to go down the "returning to smith route" Link to comment Share on other sites More sharing options...
gunner Posted December 28, 2015 Report Share Posted December 28, 2015 Its funny that the group on L has neater cut bullet holes , but each bullet hole on R group is cut wider ? If you know what i mean - like there unstable ? Are you loading the virgin and reloaded rounds exactly the same powder charge and col ? Remember the web of the case doesn't get resized and you will undoubtedly have different volume - slightly . But you would think the sticky bolt and extrator marks would be from the smaller capacity virgin brass ! - weird Link to comment Share on other sites More sharing options...
MJR Posted December 28, 2015 Report Share Posted December 28, 2015 The group on the right doesn't look like a group with a flier, it's just a bigger group. Have you checked concentricity/run out on your reloads? Have you checked capacity of the new unfired cases against your fired cases? Have you checked for a donut in the cases necks after firing? Link to comment Share on other sites More sharing options...
foxpig Posted December 28, 2015 Author Report Share Posted December 28, 2015 Both groups are with same powder and bullet weight made on the same day . All I've done is trim the brass back to lapua trim to length size that I do on all brass before loading. I don't have a tool for finding donuts. All I have is a paperclip and the feel of the arbour press when seating. As far as I can tell there are no donuts. I don't know how to check for capacity? I don't have a tool to check for concentricity. All I have is a flat table and the old roll it along method. Again nothing jumps out. Thanks for your help chaps Link to comment Share on other sites More sharing options...
MJR Posted December 28, 2015 Report Share Posted December 28, 2015 Capacity- leave the spent primer in and fill a fired case with water level to the top of the neck. Make sure the water is level with the top of the neck and use a tissue to soak away excess as the water tends to balloon above the neck if you are not careful. Weigh the case. Press a fired primer into an unfired case and repeat the process. Do the same for a fired and resized case. How far are your bullets seated into the neck? If the junction of the boat tail and bullet body are seated below the shoulder/neck junction of the case you can usually feel a donut as you press in the bullet. Link to comment Share on other sites More sharing options...
gbal Posted December 28, 2015 Report Share Posted December 28, 2015 Just to refine MJRs capacity -though I doubt that capacity would have such a large effect,it's easy to isolate it-but brass varies,from the box so: weigh say 10 virgin brass individually. Then fill with water (the curve-meniscus- is Ok and should be the same on all cases,or levelled equally).Weight the filled cases individually. Take the average. Differnce is capacity of water (accurate shooter site has usually got these for different brass) Do it all again with ten fired cases,and average those.(have a spent primer in all the cases-they leak!) Any differences within each ten will tell you something about brass uniformity for the virgins,and any differences between the virgin and fired weights with water gives chamber effects,if any. Donuts are unlikely using virgin brass that has not been reformed in any way (typically a donut comes from reducing a neck),and you don't-especially between virgin firing and second firing.The clip would reveal it too. But something is going on-if all this reveals nothing...maybe the smith deserves a chance to commment,privately..... Just a last long shot-the tight virgin group looks like 3 shots,the wilder right second loading is 5,and considerably worse- is it worse always from the 2/3 rd shot...ie isn't a dispersal effect that only shows after 4/5 shots (or shoot 5 virgins-you probably have). If you shoot some more,it's very easy to mark the virgins orientation-ink mark at 12 o'clock,and rechamber them when reloaded in the same orientation,same ink mark at 12 o'clock....might suggest a chamber issue if it helps....there has to be a (or several) reason (s) ! g Link to comment Share on other sites More sharing options...
soother223 Posted January 4, 2016 Report Share Posted January 4, 2016 Could it be worth putting them over a chronograph? That would possibly eliminate any suspicion of stock screws, mounts etc... I had a similar problem and messed around for ages.. However mine started to lose accuracy after about 4 shots.. One of those were fireforming shots. Not sure if my problem was doughnuts or the brass needed annealing?.. had a crude attempt with a small blowtorch on some of my worst cases which improved things no end! However after discussing things with spud I decided to simply replace my brass after 4 shots . Would like to know what was really happening though! Link to comment Share on other sites More sharing options...
gbal Posted January 4, 2016 Report Share Posted January 4, 2016 I can't see how a chrono would diagnose loose mounts or screws? Chronos can only give velocity information.....not dispersion causes (unless velocity is way out-only on non virgin firings,though...) But the facts are virgin brass shoots superbly,then this brass reloaded shoots poorly....that seems consistent....and It is extremely unlikely that screws/mounts etc just loosen on second firing...then tighten up when the next virgin cases are fired and repeat this... It's always sounded like a brass (maybe chamber) issue maybe an Audette banana one....it sure is perplexing but with respect "messing about" seldom helps-(and a donut is usuallly detectable fairly easily,though doesn't seem to apply here-no fireforming...and OAL consistent.... It would do no harm to chrono the shots,of course,so long as the chrono is reliable.. gbal Link to comment Share on other sites More sharing options...
foxpig Posted January 4, 2016 Author Report Share Posted January 4, 2016 Thanks for trying everyone all great ideas. I'm still waiting for our rainy season to end. When it does this is what I'm going to do I've loaded 10 new virgins.(that I will mark at 12 o'clock ) 10 just neck sized ( on their second firing) 10 bumped back to Virgin size . Then when this little test is done. I will reload the 10 virgins 5 I will just reload and fire with the 12 o'clock mark in same position as first firing. The other 5 I will bump back to Virgin size then fire in 12 o'clock marked position. All of this I will do through the crony. And I will shoot them round Robin style for fairness. Any other things you guys can think of I should try in this test. I hope this will be the end of it Link to comment Share on other sites More sharing options...
soother223 Posted January 4, 2016 Report Share Posted January 4, 2016 I can't see how a chrono would diagnose loose mounts or screws? Chronos can only give velocity information.....not dispersion causes (unless velocity is way out-only on non virgin firings,though...) But the facts are virgin brass shoots superbly,then this brass reloaded shoots poorly....that seems consistent....and It is extremely unlikely that screws/mounts etc just loosen on second firing...then tighten up when the next virgin cases are fired and repeat this... It's always sounded like a brass (maybe chamber) issue maybe an Audette banana one....it sure is perplexing but with respect "messing about" seldom helps-(and a donut is usuallly detectable fairly easily,though doesn't seem to apply here-no fireforming...and OAL consistent.... It would do no harm to chrono the shots,of course,so long as the chrono is reliable.. gbal It would eliminate stocks mouth etc.. If velocitys were inconsistent then obviously brass, loads, depths etc... If they were consistent then it's gun related. That's all I was thinking ... I hope you find the answer fox pig! Good luck! Link to comment Share on other sites More sharing options...
gbal Posted January 4, 2016 Report Share Posted January 4, 2016 Soother,maybe you have not fully followed all the previous 45 posts on this real puzzler-it looks like a chamber or Audette banana brass kind of thing (though the virgin brass fires excellently-and when reloaded with no changes-it refires very poorly.Can't be stock,screws as it keeps doing this for hundreds of rounds.... Chrono might show velociy inconsistency between virgin loads and that ex virgin identically reloaded brass (but why would that cause quite considerable dispersion of groups,unless the velocity is a fair bit different...to be continued.... gbal Link to comment Share on other sites More sharing options...
Grum87 Posted January 5, 2016 Report Share Posted January 5, 2016 How big a difference is there in size/capacity over 'new' unfired, and fire formed? Have seen a rifle(albeit factory), generate two VERY different results with the same charge and head, with full length sized brass, and fire formed brass. To the extent the FL sized showed sizes of excess pressure, and fireformed did not. Link to comment Share on other sites More sharing options...
Si-Snipe Posted January 5, 2016 Report Share Posted January 5, 2016 Hey all Can anyone answer this one. Why would a rifle shoot superbly with new Virgin brass out the box. And on the second loading of that case throw flyers?. Got me stumped . Would full length sizing cure this problem as they are only neck sized? Cheers Check for donuts (restriction at the bottom of neck). Do this by sliding a bullet into a fired case. Link to comment Share on other sites More sharing options...
foxpig Posted January 5, 2016 Author Report Share Posted January 5, 2016 Nice one si you may have helped find something here. I've been pushing bullets into fired cases. Defiantly no donuts. But on other calibers the bullets pretty much fall in the case. On this one they are quite tight. I'm wondering weather I've got a tight neck. And I'm re sizing the necks a little 2 much. I was advised on what neck bushing to get . Maybe I should turn my brass before first firing ? Link to comment Share on other sites More sharing options...
onehole Posted January 5, 2016 Report Share Posted January 5, 2016 Nice one si you may have helped find something here. I've been pushing bullets into fired cases. Defiantly no donuts. But on other calibers the bullets pretty much fall in the case. On this one they are quite tight. I'm wondering weather I've got a tight neck. And I'm re sizing the necks a little 2 much. I was advised on what neck bushing to get . Maybe I should turn my brass before first firing ? Hi,,,been catching up on this post,,,,,,from what you have just said I would hope you were told by your smithy if you were given a tight neck or min spec chamber come to that,,,,?,,,Cant explain your new brass giving good accuracy but would certainly think you have some tight situation going on in that neck.Benchresters may work with tighter tolerances but they tend to run very clean chambers,,,,,in the field and not so often cleaning regime it wont be long before clearances are taken up with residue etc,,,,,,,,Try working with at least 3 preferably 4 thou clearance on your necks,,,,sounds like you are gonna have to turn some brass!! let us know how you get on,,,regds,,,D Link to comment Share on other sites More sharing options...
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