50 yard vs. 100 yard Accuracy?

[DanTheFarmer]

Hi All,

The Short Version - Does accuracy at 50 yards on a centerfire hunting rifle indicate accuracy at 100 yards and longer ranges?

The Longer Version - I had a rough day at the range while working up some loads for my 257 Roberts and my 7mm-08. It was stinkin' hot, I was having trouble with my chronograph and I was shooting horribly. I mean no grouping at all. Anyway, I took a break, had some water, and shot some factory ammo at 50 yards and got a decent group. I then tried some of my loads I was working up. Some didn't group well but a couple behaved nicely. The low end loads had some spread, higher loads got better until one was an actual cloverleaf, and then the highest loads spread out again. So is the load that cloverleafed at 50 yards a good one or is the range too short to tell?

The best behaved load was a 257 Roberts with a 100 grain Hornady Interlock using H414. The velocity for the cloverleafed powder charge was right at 3000 fps. Should I load some of these up for this Fall's hunting season?
I also got decent results from 257 Roberts, 75 grain Sierra HP's using
BL-C(2). The velocity for the best load here was 3450 fps or so.

Thanks for any input.

Dan

 

[Jasper1573]

I also have those days at the range, and I put them behind me until another day.

I would reload some of the rounds that performed well and try them at 100 yds.

An accurate round at 50 yds is no guarantee of accuracy at 100 yds any more than accuracy at 100 yds guarantees accuracy at 500 yds, but it is a good starting point.

Keep working on your reloads and you will eventually find one that is good at multiple ranges.

 

[JDGray]

Since bullets spread out in a cone shape, the 50rd group will be X2 at 100yrds. Your tightest group at 50, will be the tightest at 100. Load up 20 or so, and look for repeatability

I would also try to check groups at your hunting distance if possible.

 

[Sunray]

50 is too close. Shoot for group only, off a solid bench rest, at 100. Once you have a group, sight in, high, according to a ballistics chart. The Hornady 100 grain SP, 3" high at 100 will put you on target out to 200. Drops like a brick past there. Hornady's Ballistic Calulator with more accurate inputs, temperatures, etc. will give you more accurate numbers though.
"...75 grain Sierra HP's..." Varmint bullet. Not suitable for deer sized game.

 

[gamestalker]

Anything shooting from around the 2800 fps range to 3800 fps needs to work from no closer than 100 yds. as Sunray stated above. I use 100 yds. as a refrence point and sight in to what the TBR on my RXIV range finder BDC indicates to be POI when zeroed to 300 yds.. If it says down 2.3 MOA than I adjust to that. It's an accurate method if you know your MV.
I just got back from the range with the 700 SPS in 7mm rem. mag.. It was windy but I still managed to group well. I had the wind in my face so it didn't cause much of a problem.

 

[Baldy]

Here's some info that will help you with your accuracy and tuning of your rifles.

http://www.gundigest.com/shooting-a...ing-minute-of-angle?et_mid=510697&rid=3608102

 

[Walkalong]

No, it will not.

 

[JDGray]

A bad group at 50, will certainly be worse at 100, than the cloverleaf group you shot. Granted, load development should start at 100 or farther out if you got room, but the cloverleaf group at 50 would be a great starting point for tweaking.

Would be intresting to set paper targets at 50, 100, 150yrds in perfect alignment, to watch the same group as it progresses down range

 

[Walkalong]

The only trouble is, you don't shoot that group at 100, you shoot it at 50. You shoot a different group at 100 yards.

In BR I always preferred to shoot at 200 yards. I felt like I shot better at 200 than 100. Perhaps it was only in my head, but that matters. Some folks hated shooting at 200 and much preferred shooting at 100. Bah, all in their heads.....

I did shoot well at 100 yards from time to time.

 

[BigN]

A clover leaf group at 50 yards may not even be close at 100 yards. It's not much of an indication of how you'll group at the longer ranges. Unless of course, your max hunting/target range will be 50 yards, then you're all set.

 

[Clark]

With the 270 the point of impact is higher at 100 than 50.
With the 45/70 the point of impact is lower at 100 than at 50yards.

 

[Cosmoline]

I use fifty as the rough cut. You can get more information more quickly at fifty yards, and changing targets is faster. It can weed out the dogs. Plus the target is easier to see, there's no mirage to speak of and wind plays very little role. Most importantly for myself, I'm shooting with iron sights most of the time and I can get a crystal-clear target at 50 but not always at 100.

I take it to 100 for the next step, but if you are consistent at fifty and measure correctly there, 100 will just confirm what you already know.

For sighting in, as opposed to pure handload testing, then you obviously need to be shooting at your chosen range.

 

[snuffy]

50 is to close.

Some bullets do not even fully stabilize until just before 100 yds. Some don't even then. It's called "going to sleep". Some laugh at that term or even the notion that some bullets aren't fully stabilized right out of the muzzle. A heavy-for caliber/long for caliber bullet can keep wobbling through it's entire flight until it goes completely unstable and tumbles.

If I get a good looking group @ 100 yds., AND I can do it more than once, I'll move out to 200 to see if the group behaves like it should. Meaning it should be around twice the size.

 

[bigedp51]

Range will effect group size.

You could have a tight group at 600 yards and a big group at 100.

Barrel movement and vibrations will effect group sizes at different ranges.

Below is the exaggerated cone of fire we think about with groups getting bigger the farther they get from the end of the barrel BUT............



The barrel is like a tuning fork and has vibrating node points and can be more accurate at longer ranges than it is closer up. It has more effect on the lighter weight barrels and the amount they flex and vibrate.



I do not want to start an argument but by collecting the British Enfield rifle I was surprised to learn more about barrel vibrations and long rang accuracy. This deals with the British Bisley shooting ranges that go beyond 1000 yards and tuning the Enfield rifle.

Download the Canadian Marksman below and tuning/bedding the 7.62 No.4 Enfield rifle, the center bedding and fore end bedding points and up pressure weights and which rifles shot best at which distance.

The Canadian Marksman (Bedding the 7.62mm No.4 Rifle) - 1965
http://www.milsurps.com/content.php?r=305-The-Canadian-Marksman-(Bedding-the-7.62mm-No.4-Rifle)-1965

 

[kingmt]

Just for myself I wouldn't even continue to 100 if it didn't leave 1 hole at 50.

 

[Cosmoline]

Some bullets do not even fully stabilize until just before 100 yds.

I've heard that for the big fifty and even larger cannons, but not for standard high powered rifle rounds. And I've never been clear on exactly what's supposedly happening with very large cannon projectiles. I have a very hard time believing a .30 caliber bullet from a standard rifle is only going to get itself stabilized after 50 yards. These aren't gyro-pistol rounds.

 

[Eb1]

I generally shoot better at 200 yards with my .25-06. I shoot about an inch high @ 100 yards, and I am on at 200 yards with a 115 grain BT.

The groups @ 100 look like 1/2" groups sometimes, but @ 200 yards they touch. It depends more about me, and how long I let the pencil barrel of my light XL7 cool. If I shoot fast the groups open. Slower and they come together. Either way I know I am good out to 300 yards for an ethical kill on a medium sized animal. I am not saying that I can't get the rifle to shoot one hole groups @ 100 yards. Because I can. I have done it several times.

I have a 30-30 that will cloverleaf 3 shots @ 100 yards, but @ 150 the same bullet group will open up to 1 1/2". Doesn't matter it just does, and @ 200 yards with the same load I get 3-4" groups with that 30-30. I don't generally take the 30-30 into pastures to hunt deer. I take the .25-06, but in the woods 75 yards or less the 30-30 with the 125 grain HP @ 2500+ fps is a show stopper.

I would say bench shooting is 80% mental over anything else. If you have a good loading for the rifle. B.R.A.S.S. is key, and sometimes you just have bad days at the range. Don't breath right. Force the shot. Don't squeeze the trigger. Heart beats at the wrong time. You get frustrated.. On and On.

I have also noticed that if I shoot with my glasses on instead of my contacts. My POA is off by 2" because of the parallax that the glasses give me vs. a naked eye. Don't really know if any of this is relevant to your shooting today. I am just throwing this out there from my shooting experience.

 

[amlevin]

And then you can add the quality of the bullet to the equation. Some bullets just don't travel long distances without starting to wobble. The slower they go the worse they behave.

 

[Eb1]

Yes, in deed. That is exactly what I was trying to get at. Thx lol

 

[Redneckly33]

Look up MPBR. Find out what it means. If you are Hunting or just practicing. I've always thought that I should start my zero at 25 yards. You can use 50 if ya like. With this zero, as long as you're shooting a centerfire rifle with a velocity of at least 2500 ft/sec. you should be good out to 300 yards and have a group within a 6 inch circle. I personally start at 25 yards. This way I don't have to worry about holdover out to 300 yards. I'm shooting a .243 Savage model 11. It should never be over about 3.5 inches high or below 3.5 inches out to 300 yards. I hunt alot and this zero has always worked for me. I'm not trying to start a arguement, some folks zero at 100 yards, some at 150 , others 200, so own and soforth. With the 25 yard zero, i'm good out to 300, if I can be still and do my part.

 

[snuffy]

Look up MPBR. Find out what it means. If you are Hunting or just practicing. I've always thought that I should start my zero at 25 yards. You can use 50 if ya like. With this zero, as long as you're shooting a centerfire rifle with a velocity of at least 2500 ft/sec. you should be good out to 300 yards and have a group within a 6 inch circle. I personally start at 25 yards. This way I don't have to worry about holdover out to 300 yards. I'm shooting a .243 Savage model 11. It should never be over about 3.5 inches high or below 3.5 inches out to 300 yards. I hunt a lot and this zero has always worked for me. I'm not trying to start a argument, some folks zero at 100 yards, some at 150 , others 200, so own and so forth. With the 25 yard zero, i'm good out to 300, if I can be still and do my part.

MPBR - Maximum Point Blank Range.

Sighting in at 25 yards, then NOT checking that sight-in at longer distances is a recipe for disaster. The reason is you have to be measuring your group with an accurate tape measure to be SURE the group CENTER isn't too high. ½ inch too high at 25 yards interprets to be a foot and a half high at 300 yards.

MPBR is a fine way to be able to shoot a scoped rifle without worrying about hold over out to the maximum yardage, say 300 yards. Theory is that the small amount above or below the cross-hairs will put you in the heart/lung area of a normal size deer. Most high velocity modern rifles have a flat enough trajectory to put a bullet into that +- 3 inch area out to 350 yards.

55 years or so ago, the NRA put trajectory tables in the rifleman magazine. They had a shooter sight in at IIRC 12 yards! He had my 3 brothers all sight in at that distance. They had to raise their sights on the 30-40 krags they were shooting quite a bit to hit the bull @ 12 yards.

My brother John, got the only chance that year at a small fork horn that presented himself at 75 yards standing facing him on a side hill with his head lower than his butt. He shot for the brisket, the deer collapsed where he stood. The was no apparent bullet wound, certainly not where he aimed. Upon skinning and cutting him up, the bullet had gone between the horns and entered the spine mid-back. The perfectly mushroomed 180 coreloct was found in the rump! All three rifles were then checked at 100 yards, they were all at least 15 inches high!

 

[Redneckly33]

No one said don't check it out. I check at 50 & 100. Site in dead on at 25 yds. As one guy said, you should put 3 shots in the same hole. I agree. When you get to 100 yards, adjust for windage only. Will you be high at 100? Sure you will. Center up your shot at 100 with windage only. Your are shooting into an imaginary circle of 6 inches. Your true zero with the .243 will be some where in the neighborhood of 255 to 270 yards. A Rimfire Rifle zero should start at 12.5 yards. In the State I live in, there are very few times you will shoot a Deer much over 100 yards. the furtherest I have personally killed one was between 200 to 225 yards. Most shots I take are between 25 to 80 yards. There is that small chance at a longer shot. If it comes up, I'm good to go. I knew when I made that post,I could get ready for an argument. My advice to anyone is to zero where they have the most confidence. I'm confidant with the zero technique I use. I ain't as good as I once was, but I'm as good once as I ever was.

 

[snuffy]

No one said don't check it out. I check at 50 & 100. Site in dead on at 25 yds. As one guy said, you should put 3 shots in the same hole. I agree.

You and I aren't the only ones reading this thread.

I've always thought that I should start my zero at 25 yards.

The "start" is the only thing that implied you might check at longer ranges. This is a public forum. You don't have to be a member to view the threads. Some 18 Y.O. kid with no father, uncle or other adult to teach him, see's this, sights in his brand new rifle at 25 yards. He goes hunting, shoots over the back of a deer at 150 yards because he saw it on the internet that that's the way you do things.

Some of us hunt bean fields or open areas with flat shooting rifles. Theory of trajectory is fine, but unless you KNOW the actual velocity of your rifle, the trajectory tables are useless. That means putting targets up at the ranges you hunt to find out what's really happening.

 

[Redneckly33]

Snuffy, No offense intended. I thought about it before I posted and decided to do it anyway. I tried to shorten it up because I type so slowly. There are numorus forums and places to check things out. There are also numerous ways to zero a Rifle. that ain't the only way. I guess I should also have said, to do this and make the one hole shot at 25 yards is to have a sight Vice. I'm 62 years old and I ain't what I used to be. Your points are well taken. In the future, if I decide to post, I'll think it thru a little better. I am to old to argue over sighting in a Rifle. I'm just saying this has worked well for me. It may not for others. I read your post and agree with alot you had to say. If you are sighting in with this method, it saves alot of ammo and a lot of walking. Everone may not reload as I do and probably you also. Probably everyone on this thread does or they wouldn't be on here looking. Perhaps I assumed to much from people. You Know what asuming will do for you. It will make and ass out of you & me. I'm making a peace offering. I have no desire to continue arguing over this. I should have also said that having a chronograph, which I have, is a must. You have to know, as you stated, what the trajectory, ballistics, is for the round you intend to shoot. Everyone may not have the time I have for all of this. I'm retired. Thats all I have is time.

 

[Walkalong]

sights in his brand new rifle at 25 yards. He goes hunting, shoots over the back of a deer at 150 yards because he saw it on the internet that that's the way you do things.

Had a grown man go to the range with me with his 300 WSM that he had sighted in at 25 yards. He said by "the chart" it would drop something like a foot at 300 yds. I told him it would not, that I had not looked at any charts, but it just wouldn't. He would not hear of it. After missing a 15" round steel plate at 300 yards about 4 times he got all flustered and asked me to try. I aimed dead in the middle and hit about one inch off dead center. He wanted to know where I aimed and I told him. Still didn't believe. He had to try it himself to believe it. Then he was just bewildered.