0.5 MOA

[Big Al]

This seems to be a widely regarded benchmark for a fairly accurate rifle when shot at 100yds. Is it normal for this standard to drop as distance increase for Joe Average?

 

Would you expect a man that can shoot 0.5 moa at 100 to be able to shoot this same 0.5moa standard at 200yds?

 

Im finding that as the distance increases I cannot hold this standard, I have a scope which is powerful and also precise enough to shoot at 200 but Im not able to hold a 1" group, best I can get is 1.5" on a good day, I understand the concept of MOA but does distance also make it more likely that your groups will enlarge?

[MJR]

Yes, shooting 1/2 moa at 100 is a very different kettle of fish to 1000yds. Besides shooter skill/error you have a lot more environmental effects coming into play as the range increases. A person that can hold 1moa at extended range on a regular basis is doing very well.

[ds1]

with more distance there are more variables, the main one being wind......which is why you don't see that many 5" groups at 1000 yards (compared to 0.5" groups at 100 yards). Other differences help or hinder such as bullet bc and case capacity.....a 6mmbr is going to outshoot a 6ppc at 600m most days.

[jcampbellsmith]

Yes, shooting 1/2 moa at 100 is a very different kettle of fish to 1000yds. Besides shooter skill/error you have a lot more environmental effects coming into play as the range increases. A person that can hold 1moa at extended range on a regular basis is doing very well.

Agree with all the comments above. One other thing I've noticed is that I've developed a load that appears to perform at short ranges. When I've checked the load at longer ranges it has been very poor. I now try to test any load at as long a range as possible. For my stalking loads, I like to try them at 230 yds just to see how they perform out there on paper.

 

I shot one fly target earlier in the year at 580 yards and although my left/right reading of the mirage/wind was dire, five shots held a 1/3 MOA elevation, so I was pleased with that. If my load is holding 1/3 MOA elevation in good conditions with the rifle fully rested, then I'm reasonably happy.

 

Regards

 

JCS

[ds1]

just for that which promotes growth and vigour and giggles try, from cold bore 1 shot at 175 yards, more the target to 560 yards, one shot...repeat for about 10 distances but not sequential.....55 yards, 620, etc.....all one on the same target....mark each shot. It will not look as nice as group shooting or even going longer step by step 100, 200, 300 as you learn what the wind is doing but it is more representative of what you can expect when after mr fox.

[gbal]

Al,in a word yes.

In many more words,much of what other posts say,but even more factors increasingly come into play.

With distance,other factors that are very small at 100 (say) are no longer negligible,so you just can't pro rata group size at increasing distances.Shooter wind reading error is one major factor,and so is very slight shooter/rifle movement-which is effectively angular,and starts to noticeably increase group size.

But there are factors more intrinsic and independent of the shooter-it is rather sobering to see a detailed analysis-done proper,with the math;these include Coriolis effect (shooting east v west),air density effects;gyroscopic drift;muzzle velocity variation (and more!)

Here's one for a 6mm,1/2 moa at 100y,80g @3000,shooting at only 300y (elevation/windage errors)"

 

wind speed error 2mph error in 5 mph -1.01/2.5

coriolis -0.23/0.13

MV -10fps -0.16/0

air density +5% -0.29/0

gyroscopic 0/0.40

 

TOTAL -1.68/3.04

 

Remember some of these can go the opposite way eg,+10 fps will add +0.16 to elevation:and this will be effectively random in a string of shots,so doubling that effect of bullet dispersal.

 

You can,tough getting complex,plot these out,giving maximum dispersal for the worst case combinations,left /right/up/down.And of course the actual intrinsic precision-1/2 moa ie 1.5 " at 300.

 

Running all this gives a MER (Maximum Effective Range) - let's take hitting a six inch gong -we get an MER of.....just under 250 yards !!

Clearly better wind reading will increase that (though 2 mph error in 10mph is better than most can get in the field) but you can do little about most of the others (more velocity is no help,though reducing the SD of velocity will help.Remember this is the extreme-many many shots will be very comfortably better,but some will push out the group (ie be an unexpected clear miss). 5 shot groups are probably not enough to capture all the dispersal possible-see what happens to 1000y shooters with 10 shot strings,compared to their 5s.

 

Whatever the fine detail-remember this is perfect range measuring and dialling-and yes,almost all scopes have some dialing in error,no shooter twitch etc-this goes a long way to explain why the .25 moa rifle is not a guaranteed crow buster at 300y.

 

gbal

[247sniper]

What rifle are you shootig and what distances at?

[gbal]

Al, Just to add a little-for the really really good bench rest shooters, 25 shot aggregates at 200y are pretty close to double those at 100y,but beyond the wind (etc!) begins to bite.

So it can be done,but not by Joe and his factory stick.

 

Just for the hell of it -and the 'my ***** shoots .25 all day long' -which I was a little sceptical of,having seen a lot that could not keep twice that for two hours BR competition, I plotted one season's 6PPC BR rifle (not a *****-the real thing) shots-thats 5x5 x 6 comps....150 shots.

 

Since BR are shooting for group,and don't want to remove their precise aiming mark,it's usual to have the rifle shooting 'off' a tad- mine was set to shoot about an inch low,and inch right.This was not changed over the season- used hold off for wind (not very well,sometimes). Clearly the wind on different days would have had some effect,say 1/4 inch.

I made a transparent mask of the target,and by lining it on the convenient BRtarget square,could plot any target shots with an ink marker pen.The superimpose on the next target ,and so on.

The total group,so plotted,was coverable by a 10p piece- so we have a .25 (or better) precision rifle,that keeps within an inch over several months,at least-for at least 150 shots,and probably better,since general wind POI was not corrected,and might well be worth 1/2 inch.

 

Will it shoot 1" at 400 yards....no bets,especially for 150 shots...even in an air conditioned-oops,no-they have minor air eddies-tunnel.Is it OK on crows at 200,probably!

 

For more real world data,try to see the Diggle egg shoot scores,on the pre egg ground hog targets (?9x3'?)great shooters and rigs,3 head shots at 100 are routine,2/3 body hits at 300 frequent,and at 500 the modal shot is a miss.(Diggle does tend to be windy,but the gear v good)

 

g

 

ps I've thought of two more factors-there is a post code lottery one..NE makes shooting more tricky,and this correlates with more,and less predictable wind.

More of concern to us,Al-there is a phone code factor: 016******* phone subscribers must face more challenging conditions,for no reason that I can discern.The fourth digit may be crucial-7 making it tougher than 6 (or is it vice versa!) :-)

[Brillo]

On a good day at my home range, Severnside, (and by this I mean 15 mph wind or less) I can easily hold a sub 1/2 moa group at 100 yards with any of my rifles. This leads me into a false level of confidence that I can achieve it at other distances. On the same day, in the same conditions, I can hold the same at 200 yards.

The implication is that I should be capable of hitting a 1 1/2 inch group at 300 yards, a 3" group at 600 yards and a 5" group at 1000 yards. But can I do it? Can I heck.

Even yesterday, where I scored a personal best at 300, 600, 900 and 1000 yards at Bisley, I couldn't hold a 1/2 moa every time at those distances.

Wind obviously plays a big part in lateral movement, but yesterday the wind was kind so there must a lot of other factors that dictate group size over distance.

 

There may be a mathematical rule for this. Something like .. group sizes increase by the square of the distance from the originating test group. Or your group size increase by double as soon as you shoot a Bisley or Diggle. Or your group size doubles over distance as soon as you enter a competition.

[tackb]

theoretically yes but as is always the case the weak fleshy bit holding the rifle is the limiting factor !

 

my rifles are 1/2moa rifles or better and I can shoot that at 100m WHEN I'm on form , but what I can do is shoot moa consistently from hasty field prone positions 95% of the time .

 

most people need to practice , not buy the latest Gucci kit..............

[farmer7]

Consistent ammunition is obviously a must as well, ammunition with relatively large muzzle velocity variations can show reasonable groups closer in but once you get out there it really shows up as considerable vertical dispersion.

[gbal]

Brillo (and tackb)-the outline 'explanation' is in my post *6 (and a tad in post*8).

 

You can either be (falsely) reassured that much 'error' is not directly shooter related,or pessimistic that shooter shooting error has not been included,as it's too variable,and sometimes large!

 

The realistic optimist can work on quite a few of the factors ,but only to reduce,not eradicate.

 

And ,within some parameters,it's more about skill than cash,though 1/4 moa can be bought,and helps!

 

gbal

[Big Al]

What rifle are you shootig and what distances at?

 

The rifle is a Tikka M595 in .223 with a Begara 1:9 barrel, scope is currently a Vortex Viper 6-24x50PST and Im currently using either Hornady 55gr vmax factory loads, or home loaded 55gr SBK or 40gr vmax All 3 loads have shot 100yd 0.5 moa groups or less with good consistency either into or with the wind to try and rule the wind out as much as possible.

 

Its only been the last few months when I have started to look into the levels of accuracy I feel I need to shoot at corvids and rabbits to what I consider extended ranges, 250-300yds. Before this the rifle had an 8x56 S&B and was more of a fox gun for lamping than a long range varminter so this longer range stuff is new to me.

 

Im not keen to do my practising on live quarry so want to get my head around the levels of accuracy I should be able to produce on paper with this set-up. Ive had what I consider good success up to 200yds with far more hits than misses in under 10mph winds, my PB is a 241yd crow with 2mph wind from behind so no adjustment needed which made me think I was probably better than a recent paper punching session has revealed, I need to chrono my homeloads I think just to see if they are more consistent than the factory stuff.

 

It seems I have a good rifle and the scope is reasonable, I generally shoot from a supported position on bags from the roof of my jeep but if Im honest I dont really know what levels of accuracy I should be expecting from this set-up and if Im being too hard on myself or the gear?

[gbal]

Al,if you take wind out of the calculation(ie there isn't any wind),out to 200/250 becomes reasonably easy,with a half decent rifle etc. You also have a bit of vertical leeway on crows,but very little windage,with rabbits ,it's reversed-more windage tolerance,less vertical. You might be able to trim a few decimals too with a really good ballistic calculator that accepts atmospherics-that you can actually measure. Beyond 250,it starts to go more pear shaped,whatever you are using.Hit rates start to drop.

Gongs are good fun,especially for 'first shot hit' work,but the hit area of an 8 inch gong is just over 50 square inches,and a 4 inch gong is 12.6 square inches. I don't know the precise size of rabbits/crows in terms of fatal hit zones,but let's say (8x2.50) for bunnies and (8x2) for crows; ie 20 and 16 sq inches-with of course a different distribution-oblong not round-which has the above drop/wind differences too. Begins to look like the 4" gong performance is a better guide.

An optimistic 'improved shooter' Max 100% Effective Range for 4" is probably in the 250 yard ball park....when there is appreciable wind (can't be exact,unless we have exact 'shooter improvement' data !)

 

gbal

[Offroad Gary]

i shoot better at 300, than 100 (pro rata).

a a quality rifle will shine through at longer range.

 

as an example, on saturday i was shooting 2 rifles (and scopes), one a full custom, the other an old factory. the custom rig cost ten times that of the factory, but at 100m the factory returned equal 3 shot group sizes, for the customs 5 shot group size. if i pushed them to 300 and beyond, the custom would p!ss all over the factory rifle^.

[gbal]

i shoot better at 300, than 100 (pro rata).

a a quality rifle will shine through at longer range.

 

as an example, on saturday i was shooting 2 rifles (and scopes), one a full custom, the other an old factory. the custom rig cost ten times that of the factory, but at 100m the factory returned equal 3 shot group sizes, for the customs 5 shot group size. if i pushed them to 300 and beyond, the custom would p!ss all over the factory rifle^.

 

Gary,I don't doubt your 'theoretical' conclusion for a moment-it's in line with what I was saying- intrinsic rifle precision may need some time to be readily measureable,and superior.

However,the issue of shot dispersal is confounded here-ie the 3shot group is less likely to show deviations than is the 5shot group.

 

Basically,to establish that the custom rig is superior,and will shine through,you'd need something no less than 10/20 shots from each at both distances....which is why I did the 150 shot 'test' (but of course I didn't do the 'old factory one'....my 'old factory rifle' had shot some .25 moas,indeed even such aggregates,but was past it's prime,and by definition as a record holding rifle,not representative...and there is only so much slog I can take to confirm what is pretty well established anyhow....

I would not be too sure that all the other factors which come into play-extrinsic to the rifle's precision-might not somewhat diminish the custom's superior piss factor,but I'm pretty sure which rifle would win.

 

On another quiet day,I worked out that given a .5 factory and a .25 custom, reducing moa by .1 came at about £1k-and was not guaranteed.....and only in this restricted envelope-you can't buy a .05 moa rifle for another £2K !!

 

gbal

[garyw]

yesterday at diggle ranges we had a 1000yd br shoot.of all the groups shot by 25 shooters only 2 groups of 5 shots went under

4.5" -

3 groups of 5.62" and under.

9 groups under 8" one of these was actually a ten shot group by Steve Barrett who i think broke the record with his 7.507" 10 shot group.

calibres ranged from 6br-308-.30 boo boo.

 

12 shooters agged under 10" and 3 others were just a shade out.

the rest of the results will be posted by Bruce[mole-30] who shot small group 4.227" with his 6br.

yesterday was about as good as it gets at diggle so some shooters were on there game.

this is just to put into perspective about shooting 0.5 moa out to distance - its not easy

[JDBenelliM1]

i shoot better at 300, than 100 (pro rata).

a a quality rifle will shine through at longer range.

 

as an example, on saturday i was shooting 2 rifles (and scopes), one a full custom, the other an old factory. the custom rig cost ten times that of the factory, but at 100m the factory returned equal 3 shot group sizes, for the customs 5 shot group size. if i pushed them to 300 and beyond, the custom would p!ss all over the factory rifle^.

I'm the same as you Gary, I shot 5 rounds at 100m 200m then 300m on Sunday and my groups were near enough the same size, around 3/4" at all distances. I'm pretty sure the rifle would put hole on hole to 200m but I blame me as I still find myself tensing up just before the shot and often don't shoot, release the trigger take breath and have another go. Practise will hopefully stop this from happening. I don't have the problem when shooting foxes or crows but when I have 1 ragged hole after 4 shots the fifth is tough

[gbal]

I'm the same as you Gary, I shot 5 rounds at 100m 200m then 300m on Sunday and my groups were near enough the same size, around 3/4" at all distances. I'm pretty sure the rifle would put hole on hole to 200m but I blame me as I still find myself tensing up just before the shot and often don't shoot, release the trigger take breath and have another go. Practise will hopefully stop this from happening. I don't have the problem when shooting foxes or crows but when I have 1 ragged hole after 4 shots the fifth is tough

 

JDB-yes,it's the 'Yerkes-Dodson' law-there is an inverted U shaped curve for 'pressure'/performance-at least for many relatively unpractised athletes etc. Some adrenaline is good,but it peaks,and can thereafter become detrimental.

 

And yes,after the penultimate shot is the likely spot-hero or zero time!

 

It's also hard to recover from two poor shots- the competition is probably blown,maybe the season,and you can't get the optimum adrenaline going on that 'blown group to be' (adrenaline isn't the only thing,but a convenient coverall for mind/body here!)

 

The consistency (3/4") at 100/200/300 is curious (3/4 moa would be more in line)...I would be very happy with .25 at 300-and just wouldn't shoot 100/200-too threatening to the laws of physiks,maybe 'sighkology' too! One answer to the 5 th shot shakes,is practice,or just don't shoot it every time. In real terms ,5 shots tells very little more than 4....10/20 begins to reveal real reality! ( see the 10 shot 1000y groups-compared to the 5 shot groups,though that's mostly twitchy almost unknowable winds).

All part of the fun.of course.

g

[JDBenelliM1]

Gbal, I have surprised myself lately at the accuracy I have managed to get. I have been out a few times in very still conditions and managed a few sub 1" groups at 300m. My best being 5 shots - 0.71".

 

I'm using a TRG 22 with 30" kreiger barrel shooting my home loads which i have been developing since May. Granted these are in almost zero wind conditions and the next step is starting to shoot in poor conditions and get my wind reading better.

 

my reloading has improved dramatically over the last couple of months which has helped my groups with both .243 and .308.

 

I shot tonight with friend at 250m (270y) and this was the best group (5 shots)

 

 

My next session will be 4-500m and I'd like to think I would get sub 1/2 MOA.

 

john

[The Gun Pimp]

There are quite a few benchrest shooters on this forum and, when we meet at a comp. the conversation is often "Did you see that ****** on UKV claiming he has a rifle that'll shoot quarter MOA all day long - why doesn't he bring it here and show us then?"

 

Now, I know that no fox or crow shooter is going to risk his internet reputation by entering a BR comp. and getting blown away by full-house custom 6PPC benchguns BUT, how about a UKV match for ordinary rifles?

 

Way back before benchrest competition as we know it was 'invented' a group of Yanks would meet up every year to brag about their varmint rifles and run a sort of informal match where a shooter could attempt to demonstrate just how good he and his kit was. Rifles were rested on bi-pods, sandbags or whatever the shooter chose. Records show that there were some incredibly small groups shot. From these beginnings, benchrest was born.

 

The rules? Any rifle, scope, rests - shooting for group at 100 yards. 6PPC custom benchguns and the like would not be permitted, just your genuine field 'carry' rifles. We could run it one weekend at Diggle over winter on our benchrest range - which has a covered firing area. Entry fee would be the Diggle range fee of £15. Anyone who has shot in a UKBRA comp. would be barred.

 

Anybody got the bottle to put their rifle where there internet mouth is?

[gbal]

John,that is excellent shooting.

Under the .71 at 300 conditions,ie no wind,it's very ,very likely that you'd be shooting sub .25 at 100

I was really commenting on the surprising 'consistence' of the same 3/4 '" at each of 100,200,300y,but if done in different conditions,then the laws of physics are restored! Always a relief!!

It may also be that you are shooting better and better....just need to get those awful 3/4" 100yard groups down a bit! ('awful' only in the context of a rifle/shooter who does .71 at 300,of course.)

 

As ever ,it's consistency over aggregated numbers of rounds that tell something like the true picture,not the 'one off' group-which,if it isn't repeatable,is probably best kept quiet.Under near perfect conditions,in the "Texas Tunnel",some bench rest rifles were turning in groups approaching no dispersion (.05,and less).Although very very occasionally real BR turns in such a 'screamer'(sub.1) in the real world,it is a very rare event,given the thousands of groups shot,and even rarer for there to be successive screamers from the same rifle/shooter.

 

Sako TRG action and Krieger are a pretty good rig,and fine attention to detail in reloading pays off,so good luck with the wind reading skills. Nice when it comes together,isn't it.

 

g

[JDBenelliM1]

I'm certain I wont shoot 0.25 MOA all day long and my reaction on seeing this group was - f**k me! i must have completely missed with a couple.

 

I find the TRG very easy to shoot and when it all comes together it is great. I think the idea of shooting 10 or 20 round group is a good idea. Next time Im out ill do 10 shots at 400m and see what happens.

[JDBenelliM1]

Gbal, A kestrel is next on my shopping list!

 

John

[Big Al]

There are quite a few benchrest shooters on this forum and, when we meet at a comp. the conversation is often "Did you see that ****** on UKV claiming he has a rifle that'll shoot quarter MOA all day long - why doesn't he bring it here and show us then?"

 

Now, I know that no fox or crow shooter is going to risk his internet reputation by entering a BR comp. and getting blown away by full-house custom 6PPC benchguns BUT, how about a UKV match for ordinary rifles?

 

Way back before benchrest competition as we know it was 'invented' a group of Yanks would meet up every year to brag about their varmint rifles and run a sort of informal match where a shooter could attempt to demonstrate just how good he and his kit was. Rifles were rested on bi-pods, sandbags or whatever the shooter chose. Records show that there were some incredibly small groups shot. From these beginnings, benchrest was born.

 

The rules? Any rifle, scope, rests - shooting for group at 100 yards. 6PPC custom benchguns and the like would not be permitted, just your genuine field 'carry' rifles. We could run it one weekend at Diggle over winter on our benchrest range - which has a covered firing area. Entry fee would be the Diggle range fee of £15. Anyone who has shot in a UKBRA comp. would be barred.

 

Anybody got the bottle to put their rifle where there internet mouth is?

 

Sounds like a fun and informative day could be had, count me in if it gets off the ground.