clover

The next purchase is probably a long way off but one can't help the mind frivilously wandering towards "the next step"..

Research suggests a 6.5mm of some sort is a good choice for 1000yd. So far I'm satisfied with my newish .223 Tikka Varmint (some hopefully non-too-serious teething troubles notwithstanding) , plus they're the only manufacturer who do anything interesting / niche / target-centric in a true left-handed format; so please on suggestions of alternatives from other manufacturers

I've been looking at their two more target-oriented T3x models; the Sporter and Tac A1.

As most of you probably already know these guns are based on the same platform and both are available in blued / blacked carbon steel (sadly no stainless option) with 24" threaded barrels. Past this point they begin to differ a fair bit.

Stock: The Sporter has lovely traditionally-styled adjustable laminate woodwork while the Tac is a lot more contemporary with AR-type butt and pistol grip, along with a host of rails around the barrel.
Trigger: The Sporter has the standard single-stage unit found on most Tikkas, while the Tac has the two-stage unit also found on the arctic.
Mag Assy: The Sporter uses the standard plastic Tikka Varmint mags and trigger housing, while the Tac uses the higher-capacity double-stack mags found on the CTR and others.
Scope Mounting: The Sporter has the standard Tikka rails while the Tac has a Picatinny rail fitted.
Calibre: The Sporter is available in (amongst other larger and smaller bores) .260 Rem and 6.5x55 while the only 6.5mm offering for the Tac is the currently trendy 6.5mm Creedmore.
Mass: Somewhat surprisingly given the sizeable stock on the Sporter, it's apparently lighter than the Tac at 4.4kg versus 5.1kg with the longer barrel.
Cost: SGC list the LH Sporter at £1745, while the Tac comes in at £1845, so there's not a whole lot in it.
 

Cherry picking from both I prefer the aesthetic and probably ergonomics of the Sporter stock; especially since I don't think there is a true-LH stock option on the Tac - meaning the comb adjuster knobs may well stick into the face of a leftie. That said having had a play with a Sporter in the flesh a while ago I was a bit disappointed by the very large mag well in the underside of the stock. I also suspect that the stock / action interface might be better on the Tac given that it's a "chassis-based" system. 

I like the two-stage trigger of the Tac, although looking at a picture of the unit I think it's only really a single-stage with a bit of sprung travel to the blade; so potentially nicer in terms of usage but little different in terms of sear engagement / functionality. I've heard tales of the feed lips wearing on the plastic mags so the metal one seems preferable; also for its higher capacity. While I appreciate that the Picatinny rail is more versatile than the standard Tikka setup, I'm very happy with the Optilocks on my Varmint so would be quite happy to go this way again.

Of the three calibres on offer I'd take the Creedmore over the rest as it seems more popular (at least currently) than the .260 and more efficient than both the .260 and the 6.5x55.

Finally, comparing the specs of both guns and their cost the Tac seems to offer a lot more than the Sporter (trigger, mag system, scope rail) for not a whole lot more money; although I suspect the stock of the Sporter adds significantly to its price; since give or take the action appears the same as that of the Varmint; which in a similar format is nearly £700 cheaper!

My head says the Tac but my heart loves the appeal of the Sporter with its proper target stock in the classic 6.5 Swede chambering. Currently my wallet is shouting at them both to Foxtrot Oscar, I have no slot on my ticket and plenty to learn from the .223, so I can't see a purchase of either being imminent.. but I'd love to hear any opinions or experiences of either anyone might like to share

Thanks chaps!

10 hours ago, Brummy Mark said:

Flyers? what do you call a flyer? An unexplained change in poi for no reason? Or is it a shooter error that you can call your own?

I would go and get a box of factory ammo and a standard bullet for calibre and twist. 

I had a remmy 700 police some years ago, (bought it off flyingfisherman) I spent a while getting an accurate load, nothing special really, circa 1/2moa, but thing was, I could get less than that with cheap privi ammo and also Winchester silver tips were amazing accurate round, never bother wasting my time reloading for that particular rifle.

Then I would hasten to add that shooter error  needs to be explored- you did mention something in one of your posts about being used to  air rifle trigger, if you have been using a pcp air rifle then stepping up to a recoiling CF is a big change and will seriously show up any poor shooting position and highlight inconsistencies. Get someone to critique your positional shooting - obviously make sure that the observer knows what they are looking for against a standard criteria for solid consisted technique of position, hold, trigger control, shot release, recoil management and breathing cycle, etc.

Quote "Position was stable and i was able to hold the crosshairs within 0.5MOA with ease."  So you have a possible  positional stability straight away? - that needs to be taken out of the equation as a priority -  Get a rear bag if your not using one - if you are using one then your shooting position is not as stable as you think - I (and I would hope other marksmen on here) will be used to looking at scope reticle that is rock solid on their intended point of aim - no floating around - and with best technique available trying to follow the shot through as much as possible.

Check and double check everything, especially scope parallax and ocular focusing, do the head bob test up-down, left-right etc as a standard double check.

All the best.

Yes, I'd call a flier a shot outside the group that I can't explain. I did call a few on the last shoot but then I know these are down to me so can be ruled out to an extent. 

I'd guess the 69gn stuff I'm currently using would be fairly standard fare for the 1:8 twist barrel. I see the NRA shop have GGG 69gn stuff so I'll grab a box of that when I'm next at Bisley too. PPU also do a 75gn load but I can't find any of this locally.

tbh I'm wondering if I'm expecting too much from "cheap" ammo, although am loathe to buy any more expensive stuff while I'm unsure of my technique - just found some Hornady match .223 but that's twice the price of the HPS stuff I'm currently using!

Happy to further explore the potential for it to be shooter error; I do have experience with recoiling stuff as I also use a .357 mag lever action, however this is shot standing over much shorter ranges - as such I'm far more familiar with the stance and the expected level of accuracy is a lot less too. Prone shooting with a significantly recoiling gun is a wholly new experience to me.

I was definitely bottom of the experience pile by a long way at Bisley last month - next time I go I'll try and both get some feedback on my technique and see if someone else will shoot some groups with my rifle. I think if there is a problem with technique it will be with recoil management due to inconsistent hold and butt positioning.

My current setup is a Harris bipod up front and a bag at the rear; not that I can see it but I'm getting a fair bit of muzzle rise so I'm guessing the bipod is "hopping"; despite my efforts to pre-load it. I've also noticed that muzzle deflection under recoil is usually fairly unpredictable; always upward but often with left / right components... the way I've dealt with this in the past (with lesser-recoiling guns) is to use a light grip as I've found this is more forgiving than a tight one it's easier to be consistent when allowing the rifle to "free recoil", however appreciate that this is going to be decreasingly viable with heavier-recoiling rifles. 

On the subject of support I've got a Caldwell Deadshot Combo front and rear rest that needs filling (glass beads?) which I'd like to try in preference to the bipod; the 'pod is convenient but I'd always preferred bags when shooting off the bench. I'd be a lot more confident of my abilities off a bench,  however sadly while our range has a fantastic steel example it's not passed for anything larger than .22LR.

Off a bench and bags I can get the crosshairs dead still, realistically prone I'm probably holding within .25 MOA - not perfect but then IMO of little consequence when the rifle is shooting at 1.5-2MOA. Rule out all user error and that's still a 1.25-1.75MOA group.

I think I've got everything related to the rifle setup pegged, thanks - PX was tested as you suggest, everything nice and tight, bore recently cleaned but enough shots to allow it to foul again...

I can't do a lot other than research until I can get back to a range with some more ammo; don't suppose you can recommend any good (preferably online) resources for prone technique? I've found a few on youtube but nothing so far that really starts with the very basics.

Thanks again for your thoughts

2 hours ago, Catch-22 said:

I'd echo looking deeper at your technique. If you admit you're not comfortable and maintaining a solid and repeatable position, shot to shot, it will show up on target.

Being able to shoot consistently small groups can only be done with a good technique - regardless of the load.

As stated above, ask a fellow shooter, ideally someone proven to consistently shoot very small groups, to watch and critique your technique and offer some pointers. 

While you're about it, I'd maybe even give them a box of ammunition and ask them to shoot some groups. Having another shooter behind your gun may help to rule out equipment issues and highlight technique instead. Cheaper and quicker than replacing a scope, stock, barrel etc.

Personally, I've seen this happen to someone. They'd spend upwards of £2k on a new AR-15 but couldn't get it to shoot better than 3" at 100m. Frustrated, he asked a couple of us to have a go. All managed to put our 10 round groups into around 0.5", with the best two 5 shot groups being under 0.2". The issue - he was using a monopod (waste of time those!) and was trying to 'free recoil' the rifle, rather than have it seated firmly in his shoulder. Once he addressed these two points, he immediately went on to shoot 0.5-0.7" groups.

Thanks - most points addressed above but the AR example is somewhat heartening - it's nice to have the effect of poor technique quantified; although I wonder if a massive amount of that wasn't due to the instability of the monopod (what position was he shooting from?). I'd be interested to hear any other tips you might have for increasing consistency when shooting prone!

On 9/6/2018 at 7:13 AM, VarmLR said:

Quite simply, it could well be that the load doesn't suit your rifle as I'm assuming that Matt can't really load develop for customers due to practicalities.  There is one other trick left to try.  Find out who shoots this bullet with your barrel length and twist and find what load they developed for it.  Then ask Matt to try the same providing it is within safe parameters.  The bullet is very jump tolerant so keeping it to mag length will be fine.  FWIW my accuracy load is 24.6gr RS50 and the same for N140 both seated to mag length for a 26 inch 1/8 twist 223..

Other than that, try other factory loads at 200 and 300 yds.  If you get one that out performs the one you have then it rules out kit issues and confirms load issues.

Thanks - I'm guessing that could be the case too. I'm hoping to have reloading capability in the not-too-distant future, so it's not the end of the world if I use the remaining HPS ammo for familiarisation with the rifle / recorded use to appease the FEO until then.

I'll maybe pick up some alternative ammo in the meantime if I get the opportunity and also going to work on my prone technique as this can't be doing me any favours. Might crack out the chrono on the next excursion to see if the velocity behaviour has improved now the gun should be broken in.

I've also got a nagging feeling at the back of my mind about the stock's contact with the barrel at the breech end - I'm tempted to crack out the abrasives to get some clearance; although for now will probably content myself with investigating the contact points a bit further. 

An update. Got the chance to test the rifle again at 100, 200 and 300yd. The barrel was well-cleaned beforehand with copper solvent, 10 one-way passes of a PB brush, more solvent on a patch, dry patches until they came out dry, an oiled patch then a dry one to finish. All groups were shot from prone with a rear bag. There was a bit of a breeze but nowt too bad.

Results started off promising and went downhill..

100yd
1. 4 shot group: 3 shots into 12mm c-c (sub-0.5MOA); spoiled by a flier (2nd shot of the four) at 7 O'clock bringing the group size up to around 37mm c-c (1.5MOA).
2. 3 shot group: 3 shots into 13.5mm c-c (c. 0.5MOA). Bottom two shots through same hole. Group dispersion diagonally strung high-right to low-left. POI maybe 12mm lower than best three shots of previous group.

Making a composite of the two groups above would give a diagonally-strung group high-right to low-left of 37mm c-c - i.e. the 2nd groups would fit neatly in the space between the 1st group's main three shots and "flier".

200yd
1. 5 shot group: 4 shots of fairly even dispersion into 37mm (sub 0.75MOA) spoiled by a flier at 4 O'clock bringing group size up to around 88mm c-c (1.75MOA).
2. 5 shot group: 5 shots diagonally strung high-left to low-right, 69mm c-c (1.4MOA). Approximately same POI as previous group.

300yd
1. 5 shot group: 3 horizonally central, vertically strung into 84mm c-c (1.2MOA) further two shots at 3 and 9 O'clock bringing group size up to 162mm c-c (>2MOA).

So, it's not very clever. I can't see any trends in the groups other than they're pretty much all over the place - some otherwise acceptable (or in the case of those at 100yd very good) but with fliers; some evenly distributed, some strung in opposite directions. There appeared to be some POI shift between the two groups at 100yd; this could have been the clean barrel fouling or just the result of random distribution over two groups, within one poor group.

Group size increase with range is perhaps non-linear; possibly suggesting a stability issue but there are no keyholed shots, nor were there any at 600yd.. while this barrel should easily stabilise these bullets.

I'd like to think it's not the scope but haven't really ruled it out. I do have another I could try but am loathe to upset the mounts - thanks to getting screwed on my original choice of scope I do have a couple of pairs of spare rings, so I could get another set of bases to avoid disturbing the original setup.. on the one hand I don't want to chuck another £60 away; on the other I was considering hoovering up another set of stainless bases before everywhere runs out so I can build another set for another rifle in future using the rings I have. 

Ammo is another possibility - I've found very few reviews of the HPS Target Master I'm using, although it seems to use reasonable quality components (69gn SMKs and PPU cases). Out of curiousity I did weight the most recently fired 25 cases which came in with an extreme spread of 2.3gn / 2.3% of mean and std. dev of 0.68gn / 0.7%, which I didn't think was too bad compared to these values on 6mmBR.

When first testing the rifle I did run the first shots through it past the chrono - giving not too wonderful numbers - over 12 shots a mean of 2753ft/s, an extreme spread of 93ft/s or 3% and a standard deviation of 27ft/s or 1%. This was when the barrel was running in though, so might be an unfair representation of what the kit's capable of.

I did also notice that the meplats of some of the SMKs are fairly roughly formed and sometimes somewhat angled; while this can't do accuracy any favours I've seen similar on promo images for the bullets so I'm guessing it's not a handling issue and considered acceptable by QC. Despite this there are many accounts of these bullets performing very well, so I'm hesitant to blame them.

I'd like to test some more ammo but off the shelf I think I'm limited to GGG 69gn and PPU 75gn if I want heavier stuff. Does anyone have any experience of either of these rounds, or the HPS stuff I'm currently using for that matter?

Finally there's always me. Position was stable and i was able to hold the crosshairs within 0.5MOA with ease. Trigger control was generally good, recoil control less-so as it's not a position I'm used to and found the butt sitting in different parts of my shoulder - sometimes giving a lot of support against a bony bit; sometimes in the sofer "pocket" inside my shoulder. The 2nd 200yd group was shot with the gun tucked into the soft bit, purposefully maintaining head and shoulder position with respect to the gun during reloading, but still the group was less than great.

So there we go - tending towards subbing in another scope just to rule that out while looking to source some different ammo to try. As usual I'm always interested to hear any thoughts anyone might have

Thanks guys - some interesting discussion going on

On 9/1/2018 at 11:50 AM, Brummy Mark said:

I have very accurate .223, Lilja 1:6 twist barrel at 22" and have never tried 69gr, nor did I ever bother to try the 90gr vld which its throated for, I have 60gr Berger match varmints (h335) for foxing and 75gr Amax (N140) for longer range ie out to 1100yds, both rounds/loads shoot 1/4 moa at 100.

With 75gr shooting steel in mountain locations with extremely varied topography I have no issues at 600 to 850, after that the wind can play havoc with drop and windage, especially shooting across undulating terrain, with spurs and re-entrants several metres high/deep etc but with .308 running rounds with a very close BC, the same thing can also happen. But for that to happen across the flat gallery range, something is not quiet right, Im sure a logical investigation, starting with, as you have done, looking at things that can become loose, scopes that are defective and also adding in shooter errors.

All the best, as there is nothing more challenging mentally, than not learning why you missed the target. Until you have nailed the problem, learning can't take place.

Thanks for your support!

Sounds like you have a very nice setup and are getting cracking results considering you're not using the heaviest bullets on offer. I'd be very tempted to stick so 90gns though it though since you've certainly got the twist for it!

I can imagine how difficult shooting over the terrain you describe could be; but as you suggest my gut tells me something's amiss to cause my issues. Everything's tight as far as I can see through so it looks like an issue with the ammo, barrel, scope or driver! 

On 9/1/2018 at 7:46 PM, VarmLR said:

Yes.  People often beat themselves up about group sizes and chase tiny ES figures getting really anal about reloading, paying scant attention to bullet choice.  It's not just important, it's critical, especially where shooting in competition, to pick the right bullet.

We were shooting 600m today and several were using 20 inch .223's with 77gr smks.  No shortage of Vee bulls.  Light winds helped, but so did using the right twist with 77gr smks driven reasonably hard which was all that was needed to place a good percentage in the "4" ring.  By contrast, those of us using 6.5s were landing about the same proportion in the veebull( and that is exactly what should be expected from 6.5s!).  223 is more than capable at 600yds...it's pushing out much beyond that where it can get very sketchy, very quickly, with slower twist rifles and lighter, shorter bullets, especially when wind is thrown into the equation.

As Mark says above, at 600, on a reasonable day on a flat range, to scatter 223's across the target would suggest that something, somewhere, is not right.  I would argue that perhaps the 69smk is not ideal at that range...the 77gr HPBT being by far the better choice.  I would suggest that rather than a kit issue it could perhaps be a combination bullet and trigger technique where the spotlight should fall.  As an example, when dropping a large proportion of 6.5s into the centre, I wondered what effects at that range that slight trigger technique changes would make. I deliberately altered my trigger pull a little, and reckon that whilst still concentrating on the sight picture, breathing and body position, by adapting a technique change such as gripping a little firmer with the thumb on the grip or pulling the trigger with a slightly fuller reach, in both cases it opened up groups from around 4 or 5 inches to around 8 (ie from centre ring to 4 ring).  It also pulled them off a little to one side.  That was deliberate but still trying to keep things steady.  Don't under estimate the importance of both bullet choice and technique...both play a huge part in consistency and precision.

That's encouraging, thanks! As above I'm currently restricted to factory ammo so the 69gns are as good as it gets for now. I'm not an inexperienced shooter and after some fettling the trigger is breaking at a nice crisp 1.6lb and it's easy to squeeze with a relatively stable sight picture, so I don't think trigger technique is an issue.

I'd not rule out driver error completely as this was all at the end of a very long day plus I have little experience in shooting prone and do find consistent butt/shoulder positioning difficult. That said I'd have to be doing something pretty bad to sling them 2 mils from the middle - I can shoot considerably better than that freestanding!

Hopefully I'll get the chance to test it soon. Will give it a thorough clean before I do and start from square one again.

On 8/26/2018 at 6:11 PM, Re-Pete said:

CG Jackson trigger is 2-stage and adjustable..............and very nice.

My 223 was originally built as a TR, (the rules allow 223 or 308), and came with aperture sights, thumbhole stock etc., but no way could it compete with the 308.

I bought it for informal target practice which it does very well.

Re-Pete,

Thanks - sounds very pleasant

On 8/26/2018 at 8:50 PM, No i deer said:

Bigger is not necessarily better apparently  ?

There's is Alot of 223 owners on here.i am surprised this thread hasn't been inundated with replies.ive nearly got one a few times but everytime opted for the bigger cals.my smaller calibre of choice for next rebarrel would be a 6mm br.i watched a mate shooting his today and its incredibly accurate at 300yds.he fired about 30 shots at the 300yds f open size target and he had about 25 vbulls and five 5's.vbull is 1.5 inches.they don't call him Justin credible for nothing ?.the wind probaly blew most of them back on target ?.It's a nice soft shooter too.it will be equally at home at 600yds too.

On 8/27/2018 at 11:44 AM, Re-Pete said:

If you want that kind of performance up to 600yds, first choice has to be a 6BR with an 8 twist barrel..............plus 105 Scenar "L"'s, RS52 powder, Lapua brass, and KVB-223M primers.

A 30" barrel is nice for trying to keep 'em in the F-class 4 ring at 1000yds. On Stickledown, that can be hard, but great fun all the same................

Re-Pete

Thanks - in response to both the above my limited experience would agree - Thursday's range visit saw some time in the butts while a much more seasoned CF shooter was planting lots in the middle with his 6mm BR!

A spreadsheet is currently being constructed to compare the relative merits of some of the popular 6 and 6.5mm cartridges (BR, PPC, Creedmore, Swede, .260 Rem) as well as the venerable .308, although...

23 hours ago, No i deer said:

Fun is what it's all about.i know quite a few shooters who have the bigger more capable calibre rifles yet they choose to do it with a less capable calibre.

Indeed - I'm currently happy to be learning the ropes with the .223 at the moment and see no point in chucking more money I can't afford at missing at longer ranges with a new gun and more expensive ammo.. it's always good to do some number-crunching to allow the slow and considered formulation of what might come next though!

So.. I've had the chance to play with the rifle a little and nothing appears loose - whipped the scope and mounts off and the base to ring bolts are still holding at the 5Nm they were torqued to when initially assembled. I also tweaked the ring caps bolts again - interestingly for the 2nd time I got a uniform amount of angular displacement out of them before the torque screwdriver clicked over; however I think this might just be the plastic inserts in the rings "settling". It all certainly seems to be gripped tight enough as the scope's not moved axially in the rings under recoil.

I'm still a bit perplexed by Thursday's problems as the total movement on the target from one shot (low and extreme right) to the next (low and extreme left) was probably about 4 mil.. the calculated deflection at that range with a 10mph wind is 2.3 mil; meaning the wind would have had to have changed by around 17mph to cause that shift - 13mph if we allow 1 mil for group dispersion. I'm still not hugely convinced tbh.. by contrast earlier I was holding off for wind by around 0.5-0.75 mil which would suggest a breeze of around 2.5-3mph.. gusting to 8-9mph to push it off to the right then back the other way by the same amount to push it off to the left. Possible I suppose, but still doesn't explain the vertical component. 

Anyway, looks like I'm back to testing at short range, then. Thanks for the replies!
 

On 8/24/2018 at 7:43 PM, Chris-NZ said:

With your elevation going to hell in random directions, I wouldn't be blaming the ammo or the wind. Loose scope bases, the scope failing or severe fouling would be my suspicions in that order.

Thanks - those were pretty much my initial thoughts too. However, loose mounts aside I don't really want it to be any of the above as they point to significant expense or a really poor barrel!

Best case scenario it'll be loose mounts; although they feel solid enough and none of the other fixings had loosened significantly. The only ones I've not checked yet are the ring-to-base bolts; which I'll have a look at when I get the chance. I have found a few accounts on the net of these bolts coming loose so fingers' crossed this is the problem!

I'm away from the rifle currently so trying to second-guess the problem.. at 300yd the target backing board was around 7 mil across; making it 3.5 mil at 600yd. Shots were falling just outside the backer on either side so call it 2 mil in each direction. If the mounts are 125mm apart on the gun this would equate to a relative shift between them of 0.5mm total; which seems just about plausible in the horizontal axis if the bolts are loose (and the fit between the mounts and rings isn't great); perhaps less-so vertically although I suppose there could be some movement under recoil.

I'd hope the scope isn't the problem as it's really seen little use and is a decent model that should withstand a lot more than a .223 in a heavy rifle can throw at it.

I really can't see it being a fouling issue as it'd only had 30-odd rounds through it since cleaning last time (44 rounds total through the gun since purchase) and very little copper came out when it was last cleaned. That said there's always the possibility that I'm not doing it right / am expecting less cleaning than necessary.. surely it should do more than 30 accurate rounds between cleaning though?

Before the range visit it had 20 (one way) passes with a phosphor bronze brush and KG copper solvent, dry patches until clean then a couple of patches with carbon solvent, dry patches until clean and finally an oiled patch.. 
 

On 8/24/2018 at 10:57 PM, No i deer said:

At 600yds f class vbull is 0.5 moa which is 3 inches.the 4 ring has gotta be about 10 inches.

At 300yds it too is 0.5 moa.1.5 inch vbull.ive never owned a 223 but from what I've read and heard about this cartridge at 600yds is too far and with the heavies in a fast twist barrel it's just about possible.its about knowing your limits I guess.having a 20 inch barrel really makes it hard going so.dont beat yourself up.there is Alot of things to learn...!

Plenty of knowledge on ukv

Thanks - I'm guessing the angular size of the rings is consistent over all ranges? We were using 300yd McQueen targets at 300yds, not sure at 600yd but they looked approximately scaled.

Yes, perhaps it is just a case of recognising and accepting the limits of the gear. According to the JBM ballistics calculator the bullets are still supersonic at that range but they've lost around around 75% of their energy by that point. 

End of the day I don't regret my choice as IMO it pays to start at the bottom and .223 offers a relatively gentle and frugal introduction to centrefire. Once I've got to grips with this one and after a bit of experience have a better idea of what I want to shoot I'll perhaps look at something bigger. 

Appreciate your support

On 8/25/2018 at 10:27 AM, Re-Pete said:

223's are great fun, especially when you get in to reloading. There's so much stuff to try out. But be warned, the wind will do your head in ?

Mine's an M595 with a 30" 8 twist barrel, CG Jackson trigger set to 450grams, and a GRS laminate stock.

I load to 3050fps for 1000yds with SMK 80 grainers, and 2800fps for 600yds using Lapua brass and KVB-223M primers, powder is RS52.

On a still day, it'll shoot <2 moa at 600 yds.

Pete

Thanks - looking forward to reloading but that's probably a while off yet!

Sounds like you you have a very nice setup; obviously well-suited to greater distance with the longer tube. I considered a GRS stock for mine but if I want to do practical it won't suit weak-shoulder stuff very well and besides I really like the front-heavy balance with the current synthetic stock. 

Is the CG Jackson trigger single or two-stage? I've been spoilt by true-two-stage airgun triggers so was looking at replacements, however have got the pull down to 1.5lb / 700g with a spring change so that will probably do for now.

To be honest if your setup is doing around 2 minutes in still conditions when punting 80gn SMKs a little faster than mine's chucking out 69gn-ers, perhaps I need to re-assess what I expect from mine in a breeze!


Thanks again for everyone's thoughts - I think the plan for now is to whip the scope and mounts of to check the tightness of the base to ring bolts. If they're loose I'll pull it all to bits, re-fit them with threadlock and start from scratch mounting the scope again. If tight I'll get the gun checked again at sub-300yd to see if it's behaving itself at this range. 

On 8/24/2018 at 8:52 AM, Catch-22 said:

I'd echo what Bradders said; clean and try again once you've checked things like your scope mounts.

If you get a chance, try first at 100-300m to see how it's grouping. That should minimise any effects the wind might be having. If all looks good, then push out further to 600m. If 100-300m is still like a shotgun, and you've squared away all your screws & fastenings, then take it to a good rifle smith to take a professional look.

Thanks - looks like it's back to basics at closer range then!

On 8/24/2018 at 11:16 AM, VarmLR said:

I'd agree with the above.  Try it again at 300 yds after cleaning as this should dispel any worries about the scope, but maybe worth also doing a scope tracking test as well.  I've had something similar at Century when shooting 69TMKs.  Slight weather change threw what started as reasonable grouping from my sub 2800fps load all over the shop despite terminal velocity being theoretically well above transonic.

You don't mention whether you had a mod fitted or not (assume not?).  If you did, had this come loose?

Ta - it seems Century has a bit of a rep!

Earlier in the day I did notice that two adjacent flags were flying against each other(!) so it's evidently not going to be as straightforward as a nice, constant, measurable breeze across the range - I can certainly accept that a lot can happen over 600yd and that .223 isn't the ideal calibre for reaching out that far. One would hope for some level of consistency though; it's massively disheartening when you're putting them all consistently in / near the middle then all of a sudden you're missing the backing board completely at opposite corners!

You're correct that the rifle just had the bare muzzle - no mod or brake on the end.
 

On 8/24/2018 at 11:52 AM, Re-Pete said:

69grainers will only work on a flat calm day at 600yds. The least breath of wind, and it suddenly goes pear-shaped (yep, we've been there....)

If you have an 8 twist barrel, try 80grain bullets. SMK's work well in mine, as do JLK's. Even kept 7 out of 10 of them within the F-class 4 ring at 1000yds on one memorably flat calm frosty morning.

Memorable for Stickledown, that is............even when the flags are still, there can be turbulence, especially if you're on lanes 45-50.

Pete

Thanks - maybe I was just expecting a bit much based on a "lucky" 10 rounds or so. I'm stuck with factory ammo currently so the 69gn SMKs are about as large as I'm going to get I think.. I'm using HPS Target Master at £83/100 from the NSRA shop, which considering the bullets used (admitted with PPU cases) I thought was pretty good compared to the cost of other ammo. I have to keep telling myself that I'm just starting out so there's no point in spending the earth on ammo while I'm still getting to grips with everything and really just plinking.

I do have a stash of 69 and 77gn TMKs awaiting the eventual arrival of a reloading setup. I didn't go any larger as there seemed to be conjecture over whether I'd get enough velocity from a 20" barrel to stabilise them. There's also the cartridge length issue to consider (in relation to the mag), although I don't think this is insurmountable given that all the Tikkas are built on a large action so there's plenty of room.

How big is the 4 ring on the F-class target? I believe the bull is a minute, so the 4 is two maybe? Sounds like great shooting at any rate with a lowly .223! I'd like to have a crack at 1000yd at some point, but I think given yesterday's experience I've got a lot to learn before I bother trying!

1 minute ago, bradders said:

Was this at Bisley?

69's aren't a 600yd bullet, especially at those speeds and 600yds can do odd things to .223's

I've seen similar happen on Century with the tricky winds, and the weirdest was when we had a weather front come in that brought a pressire change with it that saw everyones shots drop off the bottom of the target

I'd say clean the rifle and try again, preferably in the early morning

It was indeed. 

I appreciate that 600yd is pushing it somewhat; it just happened that this is the ammo I have (until I can start reloading) and our club had the range booked so it would have been rude not to have given it a go.

We were shooting 2-up on a lane (alternate shots) but irritatingly my partner had just finished when it all started going squirly so I had nobody to benchmark my performance against. 

Tbh I'm totally green to centrefire (this was the first time I've shot past 100yd) so I'm not going to pretend I know all about wind.. I'm aware of the magnitudes of drift involved from ballistics calculators but was surprised by the sudden shift in horizontal drift and vertical displacement - having been happily dropping them in the bull with a little horizontal hold-off until that point.

I'm hoping to get down there again next month and might try and test the rifle at closer range beforehand to further rule out environmental factors. 

Thanks for taking the time to reply

 

3 minutes ago, bradders said:

What's the twist rate on the barrel?

1:8", 20" tube, MV is around 2750ft/s with the 69gn SMKs 

It's performed very well with these rounds until suddenly spewing them all over the place. The first very high shot (that actually went through the target holder!) showed no signs of tipping / keyholing.  

Finally got the chance to stretch the legs of the new toy today. 

At 300yd it was convincing dropping shots into around a minute / 3". Moving back to 600yd it was still keeping within maybe 1.5 minutes / 9"; less when I got the wind correction right.

Until this point I was really pleased with it until the last shot ,which printed very high - maybe 30" / 5 min. The detail ended and I had to wait a while before trying again; the first shot of the next string again around 30" high and now 40" right. The next around 30" low and 40" right, the final one before I gave up maybe 30" low and 40" left (all dims approx as gauged against squarish target holder). 

There was a bit of a breeze at 600yd however until the first wayward shot I'd been successfully holding off by no more than 2 MOA with a consistent vertical POI corresponding with the POA. The wind didn't appear to have picked up significantly when the problems began.

The kit is as follows:

Tikka T3x Varmint, .223 Rem.
Sightron SIII 10x42
Optilock rings and bases
HPS Targetmaster 69gn (SMK) 

All shots were shot prone using a Harris bipod and rear bag. I'm pretty sure it's not driver error - certainly based on the success I was having until it all went wrong. 
 
Scope mount tightness (rings and bases to rifle) was checked before the final two shot and nothing was found to be significantly loose (each fixing tightened a fraction of a turn more but this made no difference to rifle behaviour). I've not had the mounts off yet to check the tightness of the ring-to-base bolts but there's no perceivable play between the two on the gun. Stock bolts were also checked at the same time and found to be fine. 

The rifle has had a total of just under 50 round through it; all the same batch. It started playing up on the 31st shot after it was last cleaned. I ran some patches through the barrel and got out a modest amount of copper fouling (3-4 slivers on one patch) and the usual carbon. I didn't get a chance to put any more rounds through the gun after cleaning but did have a look through the bore - the scope's crosshairs appearing dead central on the target for windage and maybe 7 mils below the target as viewed through the barrel. 

So.. I'm thinking possible causes could be:

- Goosed scope, although it's not seen a lot of use and seems broadly-speaking OK when bore-sighted
- Loose mounts - still need to check ring/base screws but there's not detectable play on gun
- Excessively fouled barrel - I'd like to think unlikely given the minimal round count and lack of significant fouling on patches
- Defective ammo - possible but based on previous performance I have no reason to see why this should be the case

I appreciate that these bullets will get pushed around a lot by wind at 600yd but that doesn't explain the vertical POI shift or large changes in horizontal POI despite an apparently constant wind speed. 

The scope has been adjusted by maybe 30-35 MOA to zero, of a possible total range of 150 MOA on each axis / 75 MOA in each direction. In addition around 20 MOA of elevation were added to get me on target at 600yd but that still leaves around 20 MOA left of elevation so it's not right at the limit of its adjustment. 

 This was an irritating end to an otherwise very enjoyable day and obviously I'm now left questioning the capability of the rifle.

I'd welcome any thoughts on anything I might have missed or should check - other than looking at mount bolt torque and re-testing with the cleaned barrel (not sure when I'll get the chance) I'm at a bit of a loss as to how to proceed!

Thanks!