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VarmLR

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Posts posted by VarmLR


  1. A good niche for it is as a novelty paperweight imho.  I had one for 5 years and had quite a few safety issues with ammo, very variable ammo quality.  When I could get ammo, every batch and sometimes every box would shoot differently meaning constant re-zeroing and then about 5 in every box would have split necks with at least one or two squib rounds.  I had enough of it and got shot.  When I could get decent ammo, it shot into about an inch at 100 yds on a good day (16 inch barrel) and at 200yds wasn't near accurate enough if there was more than a puff of wind.  Great for bunny bashing to 150 yds, not much good for anything else imho.  The 22LR and 223 do everything I need for vermin control between them.  I'd like a little 17 hornet at some point as that would be a far better choice than the HMR.  That one's doomed for obscurity.  Even the ammo isn't that cheap any more. (ok still cheaper than CF but when you consider the re-zeroing with each batch of rounds, you waste 5 or 10 rounds per box so here locally at £17/50 you end up really paying £17/40 and I can almost home load cheap 223 rounds for that!)


  2. All I do with new Lapua brass is partially pass them through a sizing die to run the necks over the expander mandrel, chamfer the case mouth, load then pass the rounds through a lee factory crimp die set for a very light crimp to ensure uniformity of neck tension and shoot. I gave up FL sizing it (as I do with some other brass) because comparisons with FL sized/virgin brass showed no difference in results.  I occasionally have to use the flash hole de-burring tool but Laurie is right, by and large, Lapua brass is so good from the factory these days, you'll rarely need to (unlike some other makes).  I have a primer pocket uniforming tool but figure why use it when Lapua have made each primer pocket near identical in the first place!  


  3. I like Redding dies personally.  Quality for even the entry level ones plus the relatively simple design and decent finish, and (measured) precision put them a class above some of the entry level competition for not much more money.  Their seating die with vld micrometer insert is a gem and the vld insert I've found a must for most CM bullets I now use.  For other bits and pieces like the case holders for my trimmer, Wilson stuff takes some beating.


  4. On 6/12/2019 at 11:41 AM, MrCetirizine said:

    This was nowhere near maximum load. It was 23.5gr N140 with a 77gr SMK 40thou off the lands. I can run 24.7gr with no pressure signs (usually) but as stated, it's not worth pushing faster when 23.5gr works at the distances I shoot.

    Just so...it doesn't stop some jumping to conclusions though¬†¬†ūüėČ


  5. On 6/12/2019 at 8:14 AM, Chanonry said:

    a simpler view would be to avoid over pressurising your components

    Or to use the correct primer to start with.¬† I am not and have NOT mentioned anything about loading over-pressure components so bat that one firmly¬†back into your court.¬† I stand by my comments¬†ūüėČ

    I happen to agree though that there is a tendency for following fashionable high speed loadings.  That though clearly isn't the case here.  Accuracy nodes can be found a reasonable way under max safe pressures (or at least there's usually an accuracy node at more moderate pressures). 


  6. Thanks for the heads-up. I'll check out whether they have any data for some I use.

     

    Edit.¬† Just done that and it's spot on wrt to my own data for the 139 scenar at both 600 and 1000yds¬† That's a handy reference resource.ūüĎć


  7. 7 hours ago, MrCetirizine said:

    They were CCI small rifle primers. Not the BR ones.

    There's your issue. Well, that and possibly loose primer pockets as some brass in 223 I've found wont reload past 5 reloads (eg PPU) with stiff loads. You really do need to use 0.025" cup thickness primers with the chamber pressures in 223 or what happens especially with cheap brass like PPU, is the very slight case head bowing with each firing results in loose primer pockets after about 5 to 6 reloads and you get the primer blow back, with gas escape at the side and often a badly cratered or pierced primer.  Sometimes you can get away with standard CCI200 primers on fresh brass but why take the risk as getting a bolt or firing pin damaged can prove an expensive repair? One blown primer wont usually damage the firing pin or bolt face but repeated blow-throughs will, and you may not notice the slight sooty tell tale signs around the primer if it isn't pierced and only start to notice when you see pitting of the bolt face and then check your case heads closely.

    You'll be fine on CCI250 or KVB223-M or Remmy 7.5 or any BR primer (loads need to be reworked up obviously).


  8. Anneal the brass after each shooting if you want consistency in neck tension...it takes seconds with a half decent set up and prolongs brass life to boot.  Check out lupos annealing machines (advertises on UKV).

    FL sizing though is what I default to every time.  I'm still on the same brass batch and am up to 6 reloads without yet needing to trim the brass let alone change it!  Use SRP for slightly longer case life.  O/W you really need to anneal the necks.


  9. On 6/6/2019 at 10:04 PM, PhilM said:

    Custom Drag Models are the way forward really for long range shooting, especially when shooting through transonic and beyond - available in lots of of AB products such as Kestrels etc.

    If you’re not shooting ELR however G1/G7s suit most people well. 

    Ive always had good success using G1 advertised BCs with G1 models in calculators out to 800m or so, and that‚Äôs with boat tailed bullets, I guess the flight profile of the boat tailed bullet will always match the G7 better, but the G1 won‚Äôt be too far off. But either are trying to ‚Äúbest fit‚ÄĚ the projectile against a modelled curve, where a Doppler radar gathered custom curve (CDM) will always be better at long ranges.

    Spot on Phil.

    At least where first shot on target counts.  Usually (an I include myself here) most people tend to use the apps with approximations for BC/MV to get on target, then dial in after shooting a series of groups or test shots.  You can take that approach (and why not...it's valid?) for fun shooting, but it's a waste of time for LR vermin control (they don't stand still once a bullet thumps in several feet away) and for comp, you sometimes get very limited...or no calibration shots depending on comp and discipline.  Custom drag models are by miles the best way.

    AFAIK, Lapua are the only company currently offering limited custom drag modelling for their bullets, but it's now the defacto mainstay for military sniper training (at least in the USA).

    I have to say though I'm surprised to learn that you get "good success" out to 800m using G1 on a stated MV for boat tail bullets.  I've tried many times and its been no-where near (acceptably) close.  G7 seems to model way better once out past 300yds IME.


  10. Truth is even more confusing.  Simply put, BC's...all of them, are only approximations which attempt to describe the form factor and drag factor of a projectile at a given velocity.  It is also velocity dependant which wrt to trajectory is in itself affected by air density, temperature etc etc (not that these matter at relatively short hunting ranges but they certainly do when you get into long range).  The bible on these things is Brian Litz's "Advanced Ballistics for Long Range Shooting" wherein you'll find all the theory (and maths!) behind this subject.  If you retain just 5% of that book, you'll be doing well!

    G1 was initialised to try and predict the trajectory of early ball ammo and basic flat based pointed tip military (black powder) and is based upon that early military bullet form.  G7 is based upon a more streamlined form of spire-point with boat tail which in itself has many variables including length of tip, CoG, angle of boat-tail and length of bullet wall.

    It follows that the published figures are either presented in one of two ways:  a G1 or G7 at the stated MV (cheating), or an averaged figure based upon hunting or target distances.  

    Some manufacturers use the former but enter it into a Ballistic App and it will provide over optimistic results for drop and drift.  BC sells, it's as simple as that, and that is why so many are happy just to print optimistic G1 figures at MV on the box, which is about as useful as telling you your car has brakes but I've no idea how long it will take you to stop from 60mph!

    Sierra almost always quote an averaged G7 figure these days for their boat tailed ammo and by and large, their figures equate well with Doppler radar evaluations at different ranges, with comparisons notably done and published by Brian Litz.

    However (isn't there always one?) don't get too hung up on it, as despite what's published every rifle may shoot slightly differently (barrel twist, wear and length as well as chambering all affect the MV) so even averaged G7 won't always give you the required precision based on a stated MV (which most likely won't be your MV).  The only reliable way to calibrate your app is to beg, borrow or buy a chronograph to determine your MV and test your drops from a 100yd zero.  What you'll probably find is that quoted G1 works well for even boat tailed projectiles out to perhaps 300yds but once beyond that, drag and velocity loss really start to matter wrt form, bullet attitude (not the cheeky kind, the geometric kind!) and the effects of wind really start to kick in.  From there out, averaged G7 will provide a reasonable fit but usually not a precise fit.  To get something more reliable, you really need to measure drop (5 shot average group at each target looking for group centre) at 100yd intervals out beyond your intended range (to get a full understanding of trajectory to and beyond your intended target), using your 100yd zero and leaving the scope settings alone....well, nearly as there's a problem with that...

    The switched-on will spot the obvious issues when needing to do this out past say 300yds.  Drop and drift (even without wind) may exceed practical target boundaries (well, elevation will anyway).  The answer is to re-zero for the 300yd target and measure drop out to say 600.  For hunting/vermin control, you really probably don't need to go any further and even if you only have the land to get say data to 400 yds it may be enough to help you out.

    Choosing an app that allows a starting point whereby you input the stated (average) G7BC, then use tested drop and drift data out to your max tested range and see how that correlates to the app predictions.  You can then in Strelok Pro for one,  alter the BC "actual value" until the app gives you the same or near as damn-it drops.  Whilst you can also alter the MV figure to get a fudged fit, technically an averages BC is better practice imho.  Job done and it should be spot on for your newly developed loads.

    This though is just the start.  If you intend regularly, or not so regularly shooting beyond 400 yds with any sort of precision, you'll almost certainly be tripped up unless you also calibrate your app with powder temperature sensitivity and with differing environmental data.  At least for on-target first-shot.  I've been shooting LR for many years now and have come to realise that the more I learn about it, the more I realise I don't know!  That and there's a requirement for fastidious discipline and consistency in home loading to ensure consistency which comes from the right load, and low ES (a must for LR shooting).


  11. Hawke make a cracker in that price bracket at just under £650.  Endurance ED 20-60x85.  Compared one to some  Nikons, opticrons and a few others at similar money, it surprised me with just how good it was.  Resolution at 50x was superb.

    Better still are secondhand Kowa scopes.  For about £700 to £800 used, you'll get a cracking good optic from them, much beloved amongst bird watchers.  I used to own a Kowa medium format camera.  Could kick myself for ever selling it...simply superb optics.  


  12. ?????  Under what logic do you get to a 30mm autocannon from a 7mm?  Good grief man!

    That is not the argument I made....in fact I didn't think I was making any argument, just stating the obvious.  Serious target comp shooters have migrated to 7mm from 6,5 for 1000yds due to the blindingly obvious BC advantages of doing so.  If serious comp isn't the aim, then I was recommending the 6.5CM....up until baldie lobbed in the excellent suggestion of the 6.5 x 55 improved.

     


  13. I think that we have rather a different take on LR shooting of animals.  With the exception of vermin species, few here shoot any animals at extended ranges.  For vermin like carrion crow or fox or rabbit,  extended ranges to 600 yds may not be seen as that unusual  depending on local geography and the ability of the shot(using frangible highly effective vermin control bullets which you wouldn't use for deer).  However, very few here take medium or large game (the largest being lowland Reds) at more than 300 to 400yds, and then only because on certain areas it might be impossible to stalk closer due to terrain etc.  Most are probably taken at within 300 yds (hill) and within 100yds (woodland or mixed open lowland).  My reason for never EVER taking a shot over 250 yds on deer is because the smaller species that I stalk don't stand still for long and it only takes a fraction of a second's movement to go from an engine room shot to a ruptured gut/spoiled carcass and unnecessary suffering if it drags itself off before a follow up shot ensues.  Part of the skill is the stalk so mostly I like to get within 100 yds or ambush stalk within that distance.

     At 800yds, I'd imagine a second or more allows a lot of room for error between the trigger being pulled and the animal being struck, and that's if a shooter is even capable of half moa at that distance in varied environmental conditions.  It just doesn't seem ethical to me but there we go, it takes all sorts and I'm not here to judge what anyone else does.


  14. The other deceptive thing when reading comparative case capacities of the 260 V's Creed' is that with high BC 140gr bullets, the 260 has little to no advantage in effective charge volume because the bullet has to sit deeper into the case negating any paper advantage it might have with lighter, shorter bullets.  I hadn't considered the improved L/A 6.5 x 55 baldie...that's quite a good shout if it (as you rightly point out) hadn't been for the 7mm taking over.


  15. As above....thin primers + pierced primers = gas cutting of firing pin (and bolt face) which exacerbates the issue and means increased risk of same on all future firings.  I learned this the hard way and with .223 and 6.5CM you need to consider the use of magnum primers with a cup thickness some 5 thou thicker than standard primers to avoid this issue.  Hope you get your rifle back soon with the issue resolved and sort a revised reload recipe.

    I can heartily recommend RS62 and Murom KVB-M primers or CCI 450 for LR or KVB-223M and CCI 250 for SRP brass.  Come to think of it, I think better results were had a few years back with Remmy 7.5 primers in SRP brass (may still have some knocking about in supplies now I've reminded myself!  Obviously Remmy 9.5 for LRP).  Remmy ones are considerably hotter than the KVB or CCI magnum/BR versions from memory.


  16. The two main players imho are the ubiquitous 6.5 x 55 and the 6.5CM.  Why those two?

    Well, the 6.5 x 55 has been with us a long time and brass is available just about everywhere for it.  It's lower pressure/larger volume design means greater brass (and barrel life) and it remains an accurate calibre, with loads of sporting rifle (and ammunition) availability. I can't see this shrinking back into obscurity any time soon (not that it ever was).

    The 6.5 CM has succeeded commercially where the much older 260 Rem did not.  Who'd have thought that a (for all intents and purposes) necked down slightly smaller cased cartridge than the 260 Rem would succeed where it failed?  I can only assume that the 260 for some reason was way ahead of its time and just never took off partly down to the 30 cal being the defacto military cal of choice for so long and also of comp shooters for many years as well as hunters (the Do it all cartridge).

    Why then the 6.5 CM over the Lapua 6.5 x 47?  Well, I was torn between the two and for me, the lack of factory offerings and ammo was definitely against the Lapua, the darling of so many custom gunsmiths and comp shooters and deservedly so.  When I saw that Lapua were offering the small primer version of brass for the 6.5 CM, that sold it to me.  A very similar cartridge design to the Lapua 6.5 x 47 but with greater case capacity and the ability to shoot the heavier bullets at higher velocities without going too high on pressures.

    I tried lots of different bullets with the CM, and like Laurie, found that it performed best with the heavier 139/140grn ones shot at between 2700 and 2800fps.  Just recently I developed a load with RS62, which exhibits almost identical load/energy characteristics of the now banned (for sales) H4350 and the Hornady 140gr SST.  Sub 1/4 inch groups in small primer brass using 43.6gr RS62.  The group below shot this week shows two bullets through the same hole and one dropped slightly low.  This was using SRP brass which requires more than 1.5gr more charge to obtain similar velocities to LRP loads so don't try and emulate this in standard brass!!!

     To arrive at this loading using standard brass (LRP) then you'd be looking at roughly a shade under 42gr RS62 or slightly less, so very much in the same ballpark as Laurie's findings with his 140gr bullets (bearing in mind also that the primers used here were not "hot" cooking varieties but thicker, "magnum" primer cups).

     

    20190529_191607.jpg

     

    The results with 139 Scenars were similar, helping me to win a 100 yd "tightest group" comp last year, much to the chagrin of those normally taking the contest with .223's!  To shoot sub half moa in 16 to 23mph gusting winds with 5 shots was a challenge that the 6.5CM/139 Scenar was luckily up to.

    The 139gr groups average .25 inch with a personal best (5 shot) of 0.18 inches.  This is a pretty typical 100yd group with the Scenar:

    139ScenarGP2.thumb.jpg.7b749e80dc666eb8d4368d0e0ea0dd75.jpg

    All the above are from a standard factory Tikka Tac A1 6.5 CM, fast becoming my favourite rifle to shoot from my collection.

    At 1000 yds, it's a similar story to Laurie's findings, with the TicTac shooting 139 Scenars consistently into sub moa groups, more often than not 3/4moa,  which from a factory rifle, is impressive stuff.

    My money is on the 6.5CM not being a "flash in the pan" but is here to stay and can be thought of as a slightly larger version of the 6.5 x 47 Lapua, complete with 30 degree shoulder angle.  The 'x47 has it's die-hard admirers and so many win comps V's CM because so many more shoot in comp than CM!  I can't think, from seeing the results of both at 1000 yds, there's any advantage in accuracy of one over the other.  Sadly, I do see the 260 Rem as slowly sinking back into obscurity, this backed by all accounts by current sales figures of the two, a trend that is probably set to continue with the advent of increased choice of factory offerings for the (now decade old!) "new kid on the block" and its similarities with the inherently accurate 6.5 x 47 Lapua.  Just my tuppenceworth.

    If I was starting out again and not after an all rounder for light to medium game as well as target, I'd probably go with the 7mm-08 Rem, or similar offering, as the 7mm has a similar advantage over any 6.5 chambering as the 6.5 has over the 30 cal.  For comp, there's "no substitute for large CC's"  and the larger, slippier bullet wins out every time hence why more seem to be going over to the 7mm.  For me, the costs outweigh the advantages as my need is for an all rounder and here the 6.5CM still ticks all the boxes for me.


  17. On 4/25/2019 at 8:46 PM, Scotch_egg said:

    Is the .260 shot out?

     

    If not, get the idea out of your head. The issue with .260 is the restricted OAL when running 140gr bullets. 

    Run 123gr bullets and chop the existing barrel. 

    The .260 runs more powder than the 6.5 Creedmoor. As such will give good velocity. 

     I agree with what you say but for larger bullets, seated deeper, there's not a lot of difference in powder capacity between the two.  For lighter bullets seated futher out, the 260 has a little more capacity.  It's half a dozen of one and 6 of the other.  If I already had a .260 there'd be no real justification to change to a 6.5.

    RE barrel length, Accurate Shooter published an article where a 6.5 barrel was cut down a little at a time and velocities tested for each length.  Their conclusion was that the optimum length I think was 24 to 26 inches, and there was really little loss by the time they got to 20 inches.  I think they finished at 15 or 16 inches and were still getting reasonable velocities.  I guess the results need taking with a pinch of salt as it depends on the powder choice.  If most powder is burnt by say 20 inches, then it stands to reason you'd not lose much velocity.


  18. The mag I understand will be revised in newer rifles as it doesn't provide reliable feed, certainly in my 6.5 where rounds aren't brought up square and often take two attempts at chambering. Nose isn't properly aligned with bore so sometimes when you think you've chambered a round you've just pushed it back into the magazine.  The way to overcome it is to be slow and deliberate with the bolt, which has to be brought all the way back to the stop before attempting to feed a round.  It's a non-issue (for me at least) once you get the hang of things.  Varmint barrel in  KRG sounds like a heavier solution?  TAC chassis is great.


  19. I just use my rifle scope.  It has no problem resolving bullet holes at 200 yds at all.  I have a spotting scope too, one of the top of the range Hawke ones which is good (I can read a number plate at half a mile with it when atmospherics allow) but it's not as good as one of the older Kowas which would be my pick of the bunch.  They've been doing spotting scopes, theodolites, and military ranging optics for donkeys' years. Newer ones I've looked through don't seem as good.  However, once I'd upgraded to a PMII, the spotting scope was redundant for ranges to 300 yards.


  20. RS70 may be a little slow burning for the 6.5.  RS62 shares similar characteristics to H4350 which was the defacto "go to" powder for the 6.5 until REACH came along and works well with my 123 to 140gr bullets.

    Primers can affect both MV and consistency.  With such slippery bullets, consistency is more important than the chase for high velocity which whilst always useful to limit wind drift, is not the be-all and end all with these bullets.  My best shooting at 1000yds has involved velocities of around 2700fps with the 139 scenar and the sweet spot seems to be from 2700fps to 2800fps with the 139 bullet.

    Using SR primers, ignition energy is significantly lower than with the LR primers, and it pays to try various primers.  CCI are ok (CCI250 or BR4) but you also have the choice of the Remington 7 1/2 benchrest primers, Murom KVB-223M (don't be tempted to the standard KVB223 unless you want pierced primers and/or gas-cut bolt faces!) and Federal 205M all of which seem popular amongst the LR shooters.

    The other thing to note is any variance between powder batches.  I have found RS62 fairly consistent between batches but it is a crudely extruded powder with some large and uneven extrusions in the pot so taking extra care when measuring charges with that powder is a must. Viht N150/N160 seems better in that respect.

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