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Old October 9, 2012, 02:10 PM   #1
Pond, James Pond
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The Anatomy of L.R. shooting. So...err...what is it?

One rule seems constant: The more I learn the more I need to learn!

What I would like is a basics intro into the hardware needed to achieve in L.R. shooting.

I know that there is no substitute for training and practice and/or innate aptitude, etc, but undeniably there is also the choice of tool and this is where I’d like some clarity on the general principles.

I imagine that this all varies with calibre, but in my case all these points revolve around the .308

So let’s start with the rifle. So far I have worked out that bolt is better than semi.
Barrel length: when is long too long?
Match barrel or standard, fluted or straight?
What effect does twist rate have, and so which is ideal or which should i avoid?
I imagine the tighter the helix, the more stable the bullet, but presumably that also reduces muzzle velocity

What about the bullet? I know that a higher BC is better, but…
Long and heavy or light and short?
HP or FMJ?
BT or not?

Velocity?
Logic suggests, to me at least, that faster is better.
But is this the case, and if so, is there a point where speed becomes counter productive?

Now, I know many will be pulling their hair, explaining that it isn’t so simple so as to compress into a few lines.
I accept and respect that, but we all need to start somewhere and if I have some idea of the principles involved then at least I can start getting an idea of when a rifle or cartridge, bullet or powder charge is a good choice or not.

Think of this as a general tick-box list for a generic rifle that you could complete in order to get a rifle and cartridge better suited to long range shooting than not. The options I have provided are not limiting: add to them or dismiss them if not suitable!

So, if you answer, then thanks in advance for indulging me!!
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Old October 9, 2012, 03:24 PM   #2
kraigwy
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Quote:
What I would like is a basics intro into the hardware needed to achieve in L.R. shooting.
First, you must understand its not about the "hardware". Its about the software.

Its all about the shooter. Its about learning the fundamentals of rifle marksmanship.

IT IS NOT THE RIFLE, IT IS NOT THE SCOPE, IT IS NOT THE BULLET.

Those are hardware. Its about the software, that bing the shooter applying the fundamentals.

Forget what rifle. If your rifle can shoot 2 MOA, you're good to go.

First take what ever rifle you have. 22 is good, any centerfire would work.

Practice by dry firing. Get a good natural point of aim and dry fire. Now get lined up. Dry fire, without moving anything open your eyes and see if you're still lined up.

Sight alingement and natural point of aim are important. Trigger control is more important because you'll blow everything else with improper trigger control.. Follow throught follows.


Then get you some NRA 50 Ft small bore targets and tons of ammo. Get to where you can hit the 10 ring on these targets CONSTANTLY.

Then and only then move out. Learn the ballistics of your bullet. You can then adjust for elevation, and spin drift (if you go that far).

Learn what temp. does to your bullet. On the average a 15 degree change in temp will move your impact 1 MOA. Don't think that's only outside temp. Its the temp of the powder. If left out of the chamber and in the shade you can adjust for outside temp. If you lay your ammo in the sun, the temp will rise and you don't know how much. Same with chamber. After you shoot a while the temp of the barrel/chamber will go up. Don't let the next round set in the chamber. You never know how hot the power is so you can't adjust for it.

Only chamber a round the instant before you fire.

Now consider wind and mirage. That's gonna get you. It takes a long time to learn to adjust for wind and mirage. Most say take the wind reading at mid range (I agree with that). Wind at your firing point will be different at the target (normally).

As we know the bullet does not fly in a straight "line of sight" it goes up, and it comes down (you aim up to compensate for gravity). Your bullet may be 15 or more feet above the line of sight at mid range.

Wind at ground level and wind 15+ feet above ground will be different. You want to know the range at mid range. Which normally is the high point of the arc.

Look at a range flag at a range. Its 20 or so feet off the ground. Take another range flag and put it at eye ball or 6 ft off the ground. The two flags will be acting differently. Because the wind is different at ground level then it is at the top of the pole.

You see people use a wind meter to get the wind velocity. That works where you are standing using the meter. But that's not what the wind is doing down range.

I love wind meters, but as a training tool. Go afield with you wind meter and spotting scope. Get a wind reading then look in the scope and see what the mirage is doing. Keep doing that in all kinds of conditions. Once you learn what mirage looks like at given wind speeds you can use mirage to estimate wind.

Then you can determine what the wind is doing mid range, at 15 feet above the line of sight by focusing the scope at that point and reading the mirage.

Careful not to focus the scope on the mirage beyond the target. That often will give you a false reading, it can and will reverse the mirage.

Once you determine the wind speed you need to adjust for the wind.

That fomula is Range in hundres of yards X wind speed in MPH divided by a constant.

If you don't know the constant. Use "10".

Example: You're shooting at 600 yards in a 15 MPH (full value) wind.

R=6 W=15 6 X 15 = 90

90 divided by the constant of 10 is 9. So click 9 MOA into the wind.

The constant of 10 works well for 308/30-06 rounds.

To get a correct, more accurate constant, you can figure your constant by using a Balistic Program. From the program (if you put it together right it will give you the correct constant at any distance.

Let say you ran the balistics of your bullet and it says a full value wind for 15 mph at 600 yards correction is 6 MOA.

Fomula: R X W / correction.

So it would be range 6(00). W is 15 MPH

6 X 15 is 90 According to your balistic program you see for a full value 15 MPH wind your correction is 6. So:

6 X 15 / 6 = 15 Your constant is 15

(its different then the 10 above because I used the numbers for my 250 grn 375 instead of the 308 but you get the idea).

All the above is SOFTWARE not HARDWARE.

Forget spending big bucks on rifle/scope, etc. When you can constantly out shoot your rifle or you can constantly shoot 2 MOA at distance with what you have, then worry about getting a fancy rifle.

You see all kinds of itty bitty groups posted on the internet. But you see few clean 1000 yard targets. The X-10 ring on a 1000 yard target is 20 inches across or 2 MOA.

Like I said, its fundamentals. Get those down by dry firing. Get to where you can clean the 50 Ft NRA small bore targets, then move out to distance.

Then learn what conditions. Wind, mirage, light, temp etc does to your bullet. Spend the money on rounds down range. Get to where you can out shoot your rifle then more to the fancy high price rifles.

Sorry for the rant, but trying to buy good scores is a pet peeve of mine. It don't work. Hard work does work.
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Old October 9, 2012, 03:43 PM   #3
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EDIT: Kraigway explained it better than my jetlagged brain could. I was a bit unclear on some stuff, and missed some valid points.
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Old October 9, 2012, 04:02 PM   #4
Pond, James Pond
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Kraig, firstly thanks for the post.
The information there is gold dust and isn't being overlooked. Indeed, I am well aware that a seasoned shooter with a worn rifle will out shoot me with a Steyr SSG04. I did make this point to assuage such concerns:

Quote:
I know that there is no substitute for training and practice and/or innate aptitude, etc
I should add that I already have a rifle (CZ550) and a scope (Burris 3-12 x 50) and I hope to load my own ammo, so this is not so much about buying anything other than reloading components.
The reloading is incidentally the only aspect where I am actually trying to buy results: I'd like to load up cartridges that are better suited to L.R. Why practice with rounds that aren't as good as they could be for the job?

The goal of my post was to understand how some aspects of the equipment are more suited to L.R. shooting than others and to understand what those aspects are and why.
I can road-race in a Morris Minor or a Aston Martin: I won't be a racing god in either but one will allow for make better use of my potential...

There may come a time in the future (and I hope it does) when I can go out and buy the rifle that makes my heart flutter. Knowing about the characteristics of that rifle may allow me to buy with my head too and not just my heart.

All I want is knowledge.
What you've posted I can and will try to apply at the range or at home as I practice.
What I'm asking for I can subsequently apply to understanding and intepreting posts, questions and answers here on TFL, for example, as well as making more informed desicions for myself.

I certainly don't wish to sound ungrateful: I'm really not - you've given me a mass of excellent information that I couldn't have expected to find for myself. I would just like to also add to the other side of the equation.

I hope this dispells any concerns you might have about my motives for asking.

@The Long Shot

Thanks for your post. I should have been clearer: I already have my gear, although not as flash as some of the items on that list!!

Could you shed light on what you know about, say bullet weight and barrel twist, and how one plays off against the other? That is one of the biggest mysteries for me!
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Old October 9, 2012, 04:40 PM   #5
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Quote:
bullet weight and barrel twist
Its not bullet weight, its bullet length that determines the twist requirement.

An example, a 220 round nose bullet like made for the orginal Springfields dont require as fast a twist as.......Lets say a bolt tail VLD 220 grn 30 cal bullet.

If in doubt, go with the faster twist.

A faster twist barrel will work on shorter bullets, but longer bullets wont work in slower twist.

Once you get the bullet stabilized, you have to keep it super sonic to what ever range you're shooting.

That's the basics, but it will get you close.
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Old October 9, 2012, 06:53 PM   #6
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Keep in mind when reading this that a higher BC bullet will not make you a better long range shooter, or help you better read the wind. What it will do is lessen the consequences caused by reading the wind (and compensating with hold or a sight adjustment) wrong.

Quote:
What about the bullet? I know that a higher BC is better, but…
Long and heavy or light and short?
HP or FMJ?
BT or not?
Generally speaking, long and heavy will have a higher BC than short and light, and a boat tail will have a higher BC than a flat base.

For LR shooting, what you are after is consistency, and for that you want match bullets, almost always hollow point boat tail (although my personal favorite has a polymer point in the boat tail).

Quote:
Velocity?
Logic suggests, to me at least, that faster is better.
But is this the case, and if so, is there a point where speed becomes counter productive?
Logic is often mistaken.

BC effects velocity retention as well as wind resistance, and the difference in flight time to the target is negligible. Running some numbers, for my rifle at my home range:

6.5-06,
.264 140AMAX @ 2818 FPS, 4400ft alt, BC .550

Velocity @ 300 2394fps 1.5MOA of drift per 10mph of Full Value wind, .34 sec flight time
Velocity @ 500 2130fps 2.5MOA/10mph F/V wind .61 sec flight time
Velocity @ 1000 1551fps 6.3MOA/10mph F/V wind 1.43 sec flight time
Subsonic @ 1575 yards

.264 95gr VMAX @ 3400FPS 4400ft alt, BC .365

Velocity @ 300 2692fps 1.9MOA/10mph F/V wind .29sec flight time
Velocity @ 500 2273fps 3.4MOA/10mph F/V wind .54sec flight time
Velocity @ 1000 1412fps 8.4MOA/10mph F/V wind, 1.38sec flight time
Subsonic @ 1300 yards

The 140 load is my actual numbers for my long range rig. I have found them to be remarkably(surprisingly?) accurate.

The flight time difference to a 500 yard target is a whopping .07 of a second, and to 1000 is even less, .05 sec, as the 140 grain bullet is going faster at that point. The velocity is equal at about 725 yards. From that point on, the 140 grain bullet, that started 600 FPS slower, is traveling faster.

If the logic theory is correct, the lighter faster bullet should have less wind when it is traveling faster, but even then it comes up short, with about 26% more wind at 300 yards, and 36% more windage at 500, even though it is still traveling as much as 300 FPS faster.

In fact, if you set the table steps to 25 yards, you will see the lighter bullet has more windage from as close as 50 yards.

For a more extreme example, lets look at 20 gr .172 VMAX from a 17 Remington, fired at 4300 FPS, and compare it to the same 6.5 140 AMAX above, but fired from a 6.5X50 Japanese at a relatively light loaded 2150 FPS.

Even though the little bullet has twice the muzzle velocity of the big one, it is only equal in the wind for 50 yards, with .4 MOA drift in a full value 10 MPH Wind. By the time it gets to 75 yards, the .17 is already up to .7 MOA drift, where the 6.5 is only .5 MOA.

The .17 also sheds about 500 FPS between the muzzle and 100 yards, the 6.5 loses only ~130FPS.

Again, this is an extreme example, the .264 140GR AMAX is a really good bullet ballisticly (BC .550), and the .17 is about as bad as a bullet gets with a BC of only .185, but it does show that now matter how fast you push it, velocity won't make up for crappy ballistics.
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Old October 9, 2012, 07:11 PM   #7
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And all that fancy math, BC, velocity, etc etc goes out the window if you're off 4 MPH of wind which could be a miss at 1000 yards.

My 270 bullet has a BC of .525. Vel of 2800. And that's just what would happen if I'm off 4 MPH on my wind call. I miss by 20 inches at 1000 yards.

Of course we haven't even got to range estimation yet.

My contention is unless you can shoot what you have to its potentual, you'd be better off spending that money for that fancy rifle on rounds down range.

If you can't hold 2 MOA in the wind, how are you gonna hold a 1/2 MOA rifle any better.

It's the soft ware folks, not the hardware.
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Old October 10, 2012, 06:24 AM   #8
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Just to be clear, we are talking about long range right (>600yds)?

There's a decent sized crowd that thinks it means anything past 100yds.
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Old October 10, 2012, 09:47 AM   #9
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One other thing if 2 MOA at 1000 is your goal. . . . .if you're going to shoot your rifle at long range holding it against your shoulder in the prone position, you'll need a more accurate rifle and ammo than if you plan on shooting it as it rests atop something on a bench. If you'll be shooting from a bench, you'll need a rifle and ammo you can shoot no worse than 1/2 MOA at 100 yards to shoot 2 MOA at 1000; groups don't open up down range in a linear fashion; never have, never will.

Few, darned few people shoot no worse than 2 MOA at 1000 yards from prone. Maybe 10 or 12 out of several hundred did at this year's Nationals. And most of 'em had a coach watching the wind and telling them how much to correct for it. Their rifles and ammo will shoot no worse than about 5/8ths MOA at 1000 yards; same as the best long range benchrest rifles.

Kraig's dealt some good info on the table, but I disagree with his comment:
Quote:
When you can constantly out shoot your rifle or you can constantly shoot 2 MOA at distance with what you have, then worry about getting a fancy rifle.
Nobody can outshoot their rifle. This is another myth among others in the shooting sports. A rifle and its ammo may shoot 5 inches at 1000 yards when clamped in a return-to-battery machine rest; it is held 100% repeatable from shot to shot. A human shooting that rifle slung up in prone who can shoot no worse than 10 inches will win every match he shoots and set all the records. I know lots of top classified long range competitors whose rifle and ammo shoot that well, but they throw a party if they can keep all their shots inside 20 inches at 1000 yards. Been there; done that!!!!! Us humans holding rifles ain't repeatable in doing so.

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Old October 10, 2012, 07:56 PM   #10
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James asks.....

Barrel length: when is long too long?
If you get a 30 inch one, then you can go to Great Britian and shoot their fullbore matches with the .308 Win. That's what it takes for 147 to 155 grain bullets to remain supersonic through 1000 yards. 26 inch is good for lighter bullets from 175 to 200 grains in a .308 Win. 32 inch barrels is about the limit for 155's. One can get a .308 Win. barrel 3 inches longer then set it back 3 inches after 3000 rounds and have a virtual new barrel for much lower cost.

Match barrel or standard, fluted or straight?
A match grade barrel will shoot more accurate and therefore reflect more precisely how well you're doing. Standard barrels used oft times make it hard to tell if the barrel put that shot way out there or you did. But one needs to decide if the added expense is worth it for a match barrel based on their own shooting skills.

Straight; no flutes; fluting does nothing for accuracy and if done wrong, it ruins the accuracy of the barrel.

What effect does twist rate have, and so which is ideal or which should i avoid?
Depends on the bullet. They need to be spun fast enough to keep them point on and stable until they reach the target. If you use a .308 Win. cartridge and want a proven twist for different bullet weights, 155's use a 1:13 twist, 175's and 180's use a 1:12 twist, 200's and 190's use a 1:11 twist. For 220 grain ones, use a 1:10 twist 240 and 250 grain bullets need a 1:8 twist in a .308 Win.

I imagine the tighter the helix, the more stable the bullet, but presumably that also reduces muzzle velocity
Fast twists don't reduce muzzle velocity any measureable amount. The angle of the rifling to the bullet going from a 1:13 twist to a 1:10 twist is small. And the bullets move very slow starting into the rifling. After an inch of travel, they're well engraved by the rifling and how fast they move doesn't matter. A 22 caliber 1:8 twist presents the same rifling angle to the bullet as a 30 caliber 1:11 twist.

Spinning bullet too fast for what they need oft times causes problems. All bullets are unbalanced to some tiny amount. The faster they spin, the more centrfugal force is set up and they'll jump off the bore axis as the exit.

What about the bullet? I know that a higher BC is better, but… Long and heavy or light and short?High BC's help, but at the expense of more recoil 'cause they're typically heavier. The more recoil there is while the bullet goes down the barrel the harder the rifle is to shoot accurately. Many folks quit shooting long, heavy high BC 190 and 200 grain boattail bullets from their .308's at long range 'cause 155's recoil less; and with a 30 inch barrel, the 155's will shoot just fine.

HP or FMJ?
Hollow point; they're more accurate as their heel (body to boattail or base junction) is more perfectly round.

BT or not?
BT's are better past 300 yards. At shorter ranges, there's no significant difference for most folks.
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Old October 10, 2012, 09:16 PM   #11
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Quote:
Nobody can outshoot their rifle. This is another myth among others in the shooting sports
Yes you can.

If you have a 2 MOA rifle, and constantly shoot 2 MOA with that rifle, finding you can hold and shoot 1 MOA, then in fact you can out shoot your rifle.

It is then time to up grade.
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Old October 10, 2012, 10:29 PM   #12
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Kraig, if the rifle and ammo shoots 2 MOA at its best, there's no way it can shoot any more accurate. A 2 MOA rifle and ammo fired by someone who can hold 1 MOA will end up with a 3 MOA group on the target. Shooter errors and variables add to what the rifle and ammo do, they don't subtract from it.

If a 2 MOA rifle and ammo is held such that it shoots the same, it won't get any better; whatever's holding it has no error or variables in doing so. Everything's the same for each shot.

I understand what you're trying to get across, but it doesn't work that way. Ones holding and shooting techniques won't make a rifle and its ammo shoot any better than it does. If you have a 2 MOA rifle, and constantly shoot 2 MOA with that rifle, you're holding and shooting a zero MOA area on the target with your sights; just like an accuracy cradle or machine rest or rail gun.

On the other hand, if you've got a 1 MOA rifle and ammo but shoot 2 MOA with it, improving your technique may enable you to shoot 1-1/2 MOA if you can hold and get shots off inside 1/2 MOA. And superhumans with a 1/8 MOA hold and let off area will shoot 1-1/8 MOA groups on the target with that 1 MOA rifle and ammo.

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Old October 10, 2012, 10:52 PM   #13
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Quote:
Originally Posted by kraigwy
If you have a 2 MOA rifle, and constantly shoot 2 MOA with that rifle, finding you can hold and shoot 1 MOA, then in fact you can out shoot your rifle.
Quote:
Originally Posted by Bart B.
...if the rifle and ammo shoots 2 MOA at its best, there's no way it can shoot any more accurate. ... Shooter errors and variables add to what the rifle and ammo do, they don't subtract from it.
Both right--you're talking past each other.

Bart is correct that if your rifle won't shoot better than 2MOA, then you won't be able to shoot 1MOA using that rifle even if you are capable of it because the rifle's error will dominate and prevent you from realizing your capability.

Kraig is correct that a shooter can be better than his rifle. If his rifle only shoots 5MOA but he can consistently hold 2MOA, then the shooter is outshooting his rifle in the sense that his accuracy capability, with a more accurate rifle, would be better than his current rifle can achieve.
Quote:
A 2 MOA rifle and ammo fired by someone who can hold 1 MOA will end up with a 3 MOA group on the target.
It's more complicated than a simple addition of group sizes. It won't be a 3MOA group, but it will be between 2 and 3MOA.
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Old October 10, 2012, 11:26 PM   #14
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Mr Pond,

I have a perspective that is closer to yours than some of the very experienced shooters here in this thread. Although I have been shooting all my life, I am a noo-be at shooting in a disciplined way. I shoot the way I was taught as a boy, and I have never made any attempt (until now) to improve my technique.

About a year ago I upgraded to a nice Weatherby vangaurd in 243, and I found I could get 1 inch groups at 100 yards with almost any ammo I put through it. I found one brand of ammo that shoots a little tighter. I don't reload, don't have the time.

I have begun trying to improve my technique. I bought a few books, I am looking into ordering a DVD that KraigWy has recommended, and I am shooting more.

What I have found is that simply shooting well out to 200 yards is a great challenge for me, so much of a challenge that it may be some years before I feel the need to master longer distances. I am trying to consitantly hit bullseyes at 200 yards, and it is a real challenge. I might make 6 or 8 good hits in a row, but then I will shoot an out-lier. Sometimes I know as soon as I pull the trigger that the shot was off. But sometimes I don't realize it until I examine the target, and that bothers me. My goal is to shoot 20 rounds at 200 yards, and have all of them in a 2 inch circle. I'm not there yet, to put it mildly.

My point is that in Kraig's first post, he outlines a "shooting school syllabus" that would keep me busy for several years, shooting at 100 and 200 yards.

I would advise you to buy the weapon you want. Enthusiasm about your rifle is good for moral and keeps you interested. If you want to do some long range plinking, go for it. But don't attempt any serious long range target shooting until you have mastered the fundementals. I will go beyond 200 yards when I start hitting bullseyes with boring regularity.
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Old October 10, 2012, 11:59 PM   #15
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Quote:
James asks.....
Another great post!!!

Thanks!

That really put some meat on the bones of my understanding.

It also tells me that, while I have my .308 dies in the post, I still need to contact CZ and find out the twist rate of their CZ550 range before ordering any bullets. Still sounds likely a 150 or 155gr bullet will suit my 60cm barrel, though.

There is no sense in handicapping myself further buy making up bullets that don't match my end goal of shooting well at longer ranges!
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Old October 11, 2012, 12:08 AM   #16
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Look at their web site, the answer is probably there.

I know you are in Europe, but checking out CZ-USA, all the .308 CZ 550 models I see are 1:12, which should work for anything up to 180 grains.

Also, I don't think we ever established what exactly you mean when you say "Long Range". As "30Cal" mentions above, that phrase means different things to different people.
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Old October 11, 2012, 12:22 AM   #17
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1:12. Thanks, that's useful and I'd be surprised if it were different over here. I may call them just to double check, though!!

Long Range:
Right now everything is long range, but I hope one day to have a pop at 1000m!!
For now my ranges are 100m and 300m (no 200m targets there) and I plan to perfect those respectively before exploring any longer distances.

However, as I said earlier, even if I may not see 1000m for a couple of years, yet, I'd still like to make up and use ammo thta I've tailored to that task.

Every shot I take will be that bit more familiarity with the chosen load...
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Old October 11, 2012, 05:03 AM   #18
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JohnKSa comments about a 2 MOA rifle and ammo fired by someone who can hold 1 MOA and the group size he'll shoot:
Quote:
It's more complicated than a simple addition of group sizes. It won't be a 3MOA group, but it will be between 2 and 3MOA.
It is exactly a simple addition of shooter and bullet error on target. And if many groups were shot, they would be no bigger than 3 MOA but the smallest ones could be as small as 1/4th MOA. The rifle often shoots groups well under 2 MOA, the biggest group the rifle and ammo will shoot.

If the shooter fires a shot holding 1/2 MOA off his desired point of aim and the rifle shoots a bullet 1 MOA out the same direction, they will add directly. The bullet will strike 1-1/2 MOA away from the desired impact point. Reverse the directions for both and the error by the same amount and the bullet will go 1-1/2 MOA the other way; 180 degrees away from the first one. The two bullet holes will be a 3 MOA 2-shot group.

However, if many groups are shot in these conditions, it's possible that they could be somewhere between 1/8 and 3 MOA. The smallest ones are the result of compensation when the shooter's error is the opposite from the desired impact point from where the bullet's error puts it. Groups so shot are the records in competition.

I've shot two-inch 5-shot groups at 600 yards (1/3 MOA) and 1000 yards (2/10ths MOA) with aperture sights slung up in prone with .308 Win. I don't hold better than 3/4 MOA in prone and try to get shots off inside 1/2 MOA. But I don't claim the rifle and its ammo is a 1/3 MOA performer at 600 yards and a 2/10ths MOA perfomer at 1000.

Last edited by Bart B.; October 11, 2012 at 05:10 AM.
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Old October 11, 2012, 06:23 AM   #19
4runnerman
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Mr Pond. Wow my head is spinning with all this info here. Ya the earth rotates and if you shoot far enough that will affect your accuracy to. BLAH BLAH BLAH. Get yourself a good rifle,work up a load ( work that load up at min of 300 yards). Listen to what Kraigwy say's and practice. I started shooting 800 to 1000 this year and when you have the right set up and you learn the rules it is really not that tough. I shoot 600 a lot. I remember the first time. Um pull out the card,count the clicks,shoot. Well I did 3 shots before i went and looked ( Thinking lord knows where they went). WHen i got to target all 3 shots were 1 inch high and grouped with in 3 inches of each other Horizontally. At that point i realized it's not as tough as some make it seem. I agree with Kraigwy ( HI Kraigwy,it's your friendly pest here) I have e-mailed him many times for advice. I have listened to what he say's and applied it. The world is much nicer that way. But,I also must say to do this job you do need a set up that can do it. 1000 yards for a 308 is not a un doable thing,but it's getting there. Once you try it you will see what i mean. It's fun,it's a challange and it's a learning thing. Since i started shooting F-Class open i have learned that those people are some of the most awesome people you will ever meet. They have a ton of advice and are always wiling to share it with you. My first NRA Match i shot in i was nervous as you could be. After shooting and doing ok ( 191 out of 200 ) One of the guys came up to me and said--As we were looking at my target- Trust what your rifle is telling you. Maybe makes no sense to you,but that day i knew right away what he was talking about. As for wind and such, That is something you just have to learn ( it's a strange thing) When i did the 600 yard. Flags at 200 and 400 were flapping slow,the other flags were still?????.
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Old October 11, 2012, 07:59 AM   #20
tobnpr
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Quote:
For now my ranges are 100m and 300m
Then, that's not "long range"...don't overthink this, it's not much different than shooting at 100 yards, except that you do have to compensate a bit for bullet drop and wind.

Tons of free ballistic programs online that provide you with the bullet drop data. If you don't have a chronograph, zero at 100 yards. Then guess best you can at your come-ups until you're dead center at 300, and "back into" determining your muzzle velocity that way. Now that you know your MV, you can input it into the program to more precisely calculate your wind and come-ups for any range.

Bullet drop is able to be easily and precisely compensate for, it's wind that requires the trigger time. Good read, here:

http://www.6mmbr.com/winddrift.html
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Old October 11, 2012, 08:39 AM   #21
Bart B.
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James Pond, your 60 cm (23.6 inch) barrel will do well with 150 to 155-gr. bullets through 600 yards/meters.
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Old October 11, 2012, 09:17 AM   #22
Jim Watson
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Bart and Kraig have a lot more experience than me, so I will just say that with the gear you ALREADY OWN, I would go with a 155 gr bullet, the Lapua Scenar or a Sierra Palma or other similar. That will get you the highest BC in that weight and a relatively light bullet will moderate the recoil in a light sporting rifle.
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Old October 11, 2012, 01:35 PM   #23
Pond, James Pond
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Quote:
James Pond, your 60 cm (23.6 inch) barrel will do well with 150 to 155-gr. bullets through 600 yards/meters.
Thanks for the endorsement of bullet choices!!

I called the Sierra Palma supplier: sold out until the end of the month, but then I'm not buying before then, anyway. I'll check out the Lapua options, although it seems the local shop only stocks the Scenar in 167gr, so I may opt for the 150gr Lockbase, if Lapua ends up as my choice: that seems to have a healthy BC, too!
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Old October 11, 2012, 02:40 PM   #24
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All depends on whether his rifle likes that particular bullet...
My son's .308 shoots the 175 SMK into half the group size of the 168...
Every rifle is different.
Which is why we use different weights, different manufacturers, different powders, and charge weights.
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Old October 11, 2012, 04:45 PM   #25
Bart B.
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It's been my experience with the .308 Win. barrels I've worn out that all the 30 caliber Sierra HPMK bullets as well as several of their hunting bullets all shot sub 1/2 MOA at 100. These are weights from 150 to 200 grains. 'Course the HPMK's were more accurate, but those barrels "liked" all of them. Perhaps the reason is all those Sierra's were all the same diameter; .3082" except for the 155's that were.3084" but they shot very good, too.
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