PDA

View Full Version : You're not going to believe this.


kawasakifreak77
March 8, 2014, 06:52 PM
Or maybe you will.

I got my .35 Remington Handi rifle ('02 SB2 frame & wood, new barrel & Simmons 4x) together & out to the range Friday morning to break it in. Ammo was off the shelf Federal 200gr stuff.

The second group I shot (@100m) measured at it's widest point, 9/16"!

No trigger job, free floated forearm, etc.

Of course I wasn't sighted in yet, so I had to keep shooting & my groups went back to my usual 2 moa.

Still. I'm amazed. I've been trying to shoot a sub moa group for what feels like an eternity. Then to do it with a $200 rifle & a cheap scope. Now I just have to remember how I did it...

Brian Pfleuger
March 8, 2014, 06:53 PM
I've been trying to shoot a sub moa group for what feels like an eternity. Then to do it with a $200 rifle & a cheap scope. Now I just have to remember how I did it...

How many shots was it? If it was three, you did it by random chance, proved by the follow up groups being 4 times larger.

Bart B.
March 8, 2014, 07:10 PM
Yes, I will.

One guy holds the smallest 5-shot benchrest record group at 100 yards; .0077 inch. That rifles' other groups go up to about .375 inch or bigger.

Welcome to the world of statistical reality of assessing accuracy.

James K
March 8, 2014, 08:04 PM
I once stepped up to the line, raised my .45, and put a bullet dead center in the 25 yard X ring, a true pinwheel. Unfortunately, I kept shooting.

Jim

AllenJ
March 8, 2014, 11:41 PM
The second group I shot (@100m) measured at it's widest point, 9/16"!

Congratulations, that is a nice group and it sounds like you've been searching for it a while now.

nemesiss45
March 9, 2014, 01:14 AM
Those occasional groups are nice. I shot a 3 shot .181 MOA group at 200 yds. With my remington 700 .308 not long ago... id never claim the rifle shoots groups like that, but ill still pin it on my wall.

JD0x0
March 9, 2014, 02:13 AM
Nice, my first Ruger surprised me in the same way. After reading how everyone claims that Rugers aren't very accurate, and me not having much experience, with shooting, at the time, I wasn't expecting my holes to even touch. Much to my surprise, my first group after sighting the rifle in, was likely sub MOA. Two bullets, pretty much through the same hole, with the third one touching at 100 yards, with Remington factory ammo. 130 grain core-lokts in .270 cal.
I had less luck with the round nosed 150's (though they had devastating performance on pumpkins)
Then I tried some 150 grain spitzers and pretty much got the same results as I got with the 130's.

kawasakifreak77
March 9, 2014, 07:29 AM
Of course I figure a certain percent of it was in fact luck.

I just find it odd the first time I take this rifle out I shoot that one good group. It never happened with my other two rifles that I shoot quite often & have dialed in handloads just for those rifles.

I'm going to keep trying. Now I have a goal to duplicate.

Bart B.
March 9, 2014, 09:15 AM
This thread may show some folks why using the smallest group, or even the average of several groups, may not be the best indicator of what the accuracy of shooting stuff is that can be counted on all the time.

Arsenals use the mean radius of many dozens of shots calculated from the group center for small arms ammo. Good example for rifles is the 1965 National Match lot of .30-06 M72 ammo had 270 shots in its qualifying test group. Mean radius was about 1.9 inch; the probable average of all the 5 or 10 shot sub groups fired is about 3.8 inch. Extreme spread of all shots was about 10 inches. Most of the shots were inside 6 inches. There was 1 bullet hole closest to dead center in the group. The group with that hole and 4 others next to it had a spread of well under an inch.

This reminds me of a conversation I had with a ballistics man at Lake City Arsenal regarding a bad lot of M118 7.62 NATO match ammo back in the 1960's. We were discussing accuracy and he told me about a funny incident with a new hire. They had just shot over 200 rounds of M118 ammo from their test barrel at 600 yards and were inspecting the target. The new kid said: "Wow, look at all those 5-shot groups under an inch." The experienced ballistician said: "Yes, there's a few dozen of them scattered all over that 15 inch composite." Or something like that. . . . .

nemesiss45
March 9, 2014, 04:46 PM
Agreed bart,

I'll extrapolate on my previous post to help illuminate that point.

On the day I shot that .181, I was just sighting that rifle in to a load I had developed. I shot 3 groups. 1st was half off the target. 2nd was .5ish MOA, 3rd was .181. I mentioned it to some guys as work telling them "I am exited to see how this load will do when I can put some more groups up" I got a lot of "dont bother trying anything else, stick with that load, thats awesome"

I have since shot it some more and it has averaged about .95 MOA across a still very small statiatical set. It is by no means a bad round, but it has shot 3x the group size of that first day's average, and with a larger set of groups to tally, it will surely grow a bit more too.


I dont mean to be discouraging though. I will always be looking to shoot the smallest group I can, and there is nothhing wrong with it... and even if you only shoot that tiny group once, you still shot it.

Hammerhead
March 9, 2014, 07:20 PM
9/16" is awesome, even if a bit flukey.
I love Handis and the 35 Rem, just never found a 35 Rem Handi. Don't ever let yours go. (if you do, it's OK to sell it to me)

Sarge
March 9, 2014, 07:53 PM
There are a lot of variables which can affect each individual group and the greatest of these is the human factor. Sometimes we pull it together and shoot nearly to the potential of the gun and load. I absolutely count those groups as a indicator of what the gun and load a are capable of.

The only 'given' is that I cannot repeat them on demand. It'd be a sorry gun, that couldn't shoot better than I do.

curmudgeon1
March 9, 2014, 08:13 PM
Barrels heat up during the first few rounds fired, then start whipping a little because of the temporarily softer steel and the combustion pressure wave traveling through the barrel. True accuracy of the rifle is the first three-round group when the barrel is cool. This is most noticeable on a hot 90° f. day

nemesiss45
March 9, 2014, 09:56 PM
There are a lot of variables which can affect each individual group and the greatest of these is the human factor. Sometimes we pull it together and shoot nearly to the potential of the gun and load. I absolutely count those groups as a indicator of what the gun and load a are capable of.

The only 'given' is that I cannot repeat them on demand. It'd be a sorry gun, that couldn't shoot better than I do.

I agree, for the most part, but a true fluke would be that random chance shot where you are pulling your POA just enough in the opposite direction of where your gun is trying to send the bullet, canceling out the guns natural "inaccuracy." The chance of this happening on consecutive shots becomes exponentially less likely as you increase the number of shots you put in a group.

That is why, occasionally, you can shoot a smaller group than your rifle could, on average, if you wete to remove the human factor.

SaxonPig
March 9, 2014, 10:08 PM
Random chance? The rifle did it. Nothing random about that.

Now, can the shooter do it on demand? That's another question. But now he knows the rifle is capable of doing it.

nemesiss45
March 10, 2014, 04:27 AM
Random chance? The rifle did it. Nothing random about that.

sure there is some chance to it. I'm not saying this group is all chance, and skill ALWAYS plays a part, but an anomalously small group is a chance happening, here's how:

first, imagine your rifle is in a perfectly rigid vise, shooting at a target using a theoretical load. Many factors determine the average group size that rifle will shoot including imperfect charge weight, neck tension, case thickness, case hardness, seating depth, bullet weight, bullet concentricity, primer, flash hole, barrel rigidity, stock rigidity, the symmetry of barrel and stock rigidity, bore imperfections, etc...
Lets say a rifle under these circumstances will shoot a group like this:
http://i740.photobucket.com/albums/xx44/Sean_O_Farrell/gun_zps54d171cb.jpg

Next, imagine a shooter is shooting a theoretically perfect version of this gun with a perfect load that would always go through the same hole if shot from the vise. the shooter's skill, habits, physical condition, eyesight, etc... as well as atmospheric conditions will determine the shooters average group size.
lets say this shooter would shoot groups like this:
http://i740.photobucket.com/albums/xx44/Sean_O_Farrell/shooter_zps88a63e2a.jpg

now if we combine the guns inherent grouping with the shooters effect on the grouping, the average will tend to increase the overall group size because, half the time, the shooters input will be drawing the guns point of impact away from center. Occasionally, however, a shooter's input will counteract the guns point of impact for a specific shot in just the right amount and direction to put a shot dead center. This becomes exponentially less likely with each shot added to a group.
Lets say it happens with 3 shots, like this. purple is the gun's deviation. green is the shooters deviation. red is the combination of those 2 inputs and shows the resultant group (approximately), which is anomalously smaller than the gun's average theoretical grouping with the ammo being used.
http://i740.photobucket.com/albums/xx44/Sean_O_Farrell/group_zps3bc33551.jpg

this group size cannot be directly attributed to the shooters skill because there is no possible way for a shooter to know, on any given shot, where a shot would fall within a gun's average grouping, and thus, cannot knowingly compensate to bring a given shot closer to center.

So if a group is only 3 shots, and is significantly smaller than average for the gun/shooter, it is chance... skill plays a part... but chance is what causes the significant deviation from average.

Bart B.
March 10, 2014, 06:52 AM
Every barrel I know of whips and wiggles at the same frequencies and amounts for every round fired. They don't heat up enough to change their resonant and harmonic frequencies.

http://www.varmintal.com/amode.htm

Every bullet of a given type I know of is not exactly the same shape nor perfectly balanced nor leaves at exactly the same speed. Nor is the air they go through constantly stable for each one fired.

If these weren't true, then a test made with bullets selected for perfect balance shot from a rifle clamped in a machine rest shoot several 10-shot groups well under 1.5 inch at 600 yards. And a 40-shot group under 2 inches. Each group started with the barrel cool and shots fired once every 20 to 30 seconds. All done at dawn when the air is most stable.

Commercial factory barrels walk shot impact as the heat up from poor fit to receivers. Refit them to a squared up receiver face and that won't happen. If they're properly stress relieved.

Every rifle fired will once in a great while shoot a very tiny group. Even a few record setting benchrest rifles do that once in their life. A lot fewer do it twice.

Slamfire
March 10, 2014, 04:28 PM
Or maybe you will.

I got my .35 Remington Handi rifle ('02 SB2 frame & wood, new barrel & Simmons 4x) together & out to the range Friday morning to break it in. Ammo was off the shelf Federal 200gr stuff.

The second group I shot (@100m) measured at it's widest point, 9/16"!

No trigger job, free floated forearm, etc.

Of course I wasn't sighted in yet, so I had to keep shooting & my groups went back to my usual 2 moa.

Still. I'm amazed. I've been trying to shoot a sub moa group for what feels like an eternity. Then to do it with a $200 rifle & a cheap scope. Now I just have to remember how I did it...

Outstanding! Just ignore all the gabblings about statistical significance and truth, pin that target to your cubicle wall and tell everyone you always shoot that well.

That’s what I do. :)

nemesiss45
March 10, 2014, 04:42 PM
pin that target to your cubicle wall and tell everyone you always shoot that well.

That’s what I do.


lol!

but seriously, despite my ranting, I am not trying to say not to be proud of it. I hang my smallest groups out for all to see regardless of how anomolous they are.... there would not be much point in hanging your most statistically average group up. ;)

reynolds357
March 10, 2014, 05:54 PM
Thankfully you got a Handi rifle that was put together right. My .35 Remington TC contender pistol shoots 2.5" at 200 yards; so the .35 Rem in break action definitely has accuracy possibilities.

Bullet Bill
March 10, 2014, 06:44 PM
I once stepped up to the line, raised my .45, and put a bullet dead center in the 25 yard X ring, a true pinwheel. Unfortunately, I kept shooting.

Jim

Always happens to me me with my 1911, nail the bullseye or soda can placed out ridiculously far away on the first shot, then the following shots are a disappointment.

9/16" is awesome, even if a bit flukey.
I love Handis and the 35 Rem, just never found a 35 Rem Handi. Don't ever let yours go. (if you do, it's OK to sell it to me)

I have just never found a 35 Rem Handi handy but I still like them.


My personal best group was a 9 shot 1.0" group at 300 yards so a little less than 1/3 MOA. Its definitely a sub MOA rifle though that consistently puts down 1 MOA groups or better. (.308 Win)

curmudgeon1
March 10, 2014, 11:27 PM
Weatherby advertised their .223 rifle as sub-minute-of-angle-accurate using the first three rounds from a cool barrel as a measurement; I found this to be so. When I continued firing a rapid string of up to twenty rounds and the barrel got no-touch hot, three-shot groups grew to 1 1/2 to 2 MOA. This is with a twenty-two-inch barrel and on a pretty hot day at 100 yards.

kawasakifreak77
March 11, 2014, 03:29 AM
Oh it's stapled up on my cabinet where I keep all my other good targets. I've gotten so close with my other rifles (1 & 1/4" with my blackout, 1 & 1/2" with my Swede & 1 & 5/8" with my Winchester 67. All iron sights (: ) but now I have my sub-moa group!

Gives me something to 'shoot' for again!

Bart B.
March 11, 2014, 07:12 PM
I once put 5 consecutive Sierra 155's from my .308 into less than 2 inches at 1000 yards while the cross wind speed was changing back and forth. Used aperture sights, not a scope. None of them went where I called them.

hooligan1
March 11, 2014, 07:59 PM
Bart I would have had to be there to see that and I sfill wouldnt believe it.
Kawasakifreak it happens....just like the shirt says...

Bart what caliber shot .0077 at one hundred?

Sarge
March 11, 2014, 08:39 PM
I once put 5 consecutive Sierra 155's from my .308 into less than 2 inches at 1000 yards while the cross wind speed was changing back and forth. Used aperture sights, not a scope. None of them went where I called them.
__________________

You flinched just enough to override all the variables or that would never have happened
;)

curmudgeon1
March 11, 2014, 08:54 PM
Murphy resides at both of the extreme tail ends of bell-shaped statistical probability curves.

BingoFuel
March 11, 2014, 09:46 PM
This is an interesting thread, and one that should be read by a lot of new or mid-level shooters.
As an ex-academic that taught graduate level spatial probability and statistics years ago it always bugged me that people associate accuracy with the size of their groups. The size of of a group, or mean radius or whatever is the populate reference is really a function of repeatability which is a function of variance. But it's not accuracy.
That is, you could fire a very tight group (one with only small variance between each shot landed) but they all could be wide of the intended mark, or the target center.
Is that accurate? No, not really. Said another way, if you consistently missed your target placing shot after shot in the same hole it would be true that you are consistent, low variance, extremely repeatable. But you'd not be very accurate.
B

curmudgeon1
March 12, 2014, 03:39 AM
If a very tight group was a little wide of the bullseye, a few clicks on the horizontal adjustment of my Weatherby's scope would bring 'em right in there .... every time.:)

Bart B.
March 12, 2014, 08:20 AM
hooligan, that .0077" record's villafied in:

http://bulletin.accurateshooter.com/2013/08/mike-stinnett-breaks-the-unbreakable-record-with-0077-group/

Regarding my "lucky 5" at 1K, such is the statistical norm when all the variables cancel each other out. Had they all added up in different directions those 5 shots would have gone into about 20 inches. I called them inside about 10 inches on paper but the wind changed after I made a correction from observations in my spotting scope to when those shots were fired some 10 to 15 seconds later. My scorekeeper acknowledged that after that 15-shot string was finished as he also was watching the wind change back and forth while I was on the gun. His comment after that string of fire was "Welcome to Las Vegas. What name should we give your slot machine shaped like a rifle held by a human?" We both laughed.

It's my opinion that the smallest groups are happenstance when all the variables cancel each other out to the sum of zero. Or everything is perfect without any variables; the sum of all zeros in any direction is zero. How does one prove which one it was?

curmudgeon1
March 12, 2014, 07:18 PM
It would be interesting to witness a calibration of the instrument that measured that .0077" group.:cool:

Bart B.
March 13, 2014, 09:55 AM
curmudgeon1, calibration of the precision calipers benchresters use to measure their groups is easy. I've calibrated a couple of my own in a metrology lab on Jo blocks and noted any error. It's easy to measure groups that small as their outside edges are "blackened" quite accurately in the special tagboard paper used for targets; a single bullet hole diameter's blackened edge is exactly what the bullet is; within .0001". I've measured bullet holes made in that paper with bullets .3075" diameter (groove diameter of the barrel they came from) with a 20X loupe and their blackened edge is just that. Benchresters often use single bullet holes on sighter targets to "calibrate" their calipers for the group holes in the target.

Resolution is easy with magnifying glasses observing the edge of the caliper's caliber ring to less than .0001" As many precision machinists with high levels of skills and knowledge measuring tiny things play that game, they've no issues with scorers in stool shooting matches well qualified to meaure precicely to resolve dimensions to that level. And the average of several measurements ends up being close enough to exact and actual for benchresters' objectives.

curmudgeon1
March 13, 2014, 09:08 PM
Bart B., most experienced shooters have no problem using digital calipers to measure distribution of a shot group, but it may be a slight stretch for someone to claim a "new record" .0077in. over the old .0090in. (.00065) per side) record using eyesight alignment of the caliper edges to the ragged/blackened edges of the bullet holes, don't you think ?:rolleyes:

kawasakifreak77
March 14, 2014, 12:38 AM
This has turned into one heck of a read guys! Thanks for sharing such knowledge.

It's funny how you go about learning things as you strive to perform better at certain tasks. When such a wealth of information is dropped in your lap, you realize how much farther you have to go even though you feel as if you've achieved so much.

Bart B.
March 14, 2014, 09:40 AM
curmudgeon1, I believe that with a decent loupe on the calipers placed over the gauging rings on its glass plate, one can easily discriminate within a couple ten-thousandths where a blackened edge is relative to the gauging ring. A 10X loupe makes a .001" gap look like a .010" gap to the naked eye.

Here's a link to a popular one used these days:

http://bulletin.accurateshooter.com/2013/10/measure-groups-precisely-with-neil-jones-tool/

You can see light coming through caliper jaws when they're only .0002" apart.

It does help to have exceptional vision.

curmudgeon1
March 14, 2014, 03:27 PM
Okay, your knowledge and experience has now convinced me that the equipment shown can accurately measure bullet-hole dispersion in .0001's".
Kudos to the new .0077" champ. Now, no doubt these benchrest-shooters have given this one some thought: when someone eventually gets five bullets through the same hole, how will they know ?

Bart B.
March 15, 2014, 04:00 PM
There's a roll of paper moving behind the stationary target they shoot at. With a string of shots clustered in one hole barely larger than bullet diameter, there are separate ones on that backer target.

curmudgeon1
March 15, 2014, 05:40 PM
Ingenious ! Somehow I knew your experiences would have met up with that situation along the way. Some guys will be interested in your answer. Thanks.