quote:

Originally posted by bobtheelf:
Pshh, I'd be embarrassed by that flier in the top right.

Yeah, look at all the vertical stringing of that group! <humor>

This seems like an incredible accomplishment. I'm wondering how close to a possible minimum it might be. Is there some form of long range shooting that is basically without technical rules so that people use 200lb steel slabs and silly stiff barrels and some kind of electronic ignition actions that shows what the lower limit might actually be? Sorry if this is easily known.

quote:

Originally posted by hrcjon:
I'm wondering how close to a possible minimum it might be. Is there some form of long range shooting that is basically without technical rules so that people use 200lb steel slabs and silly stiff barrels and some kind of electronic ignition actions that shows what the lower limit might actually be?

I don't know much about bench rest rules. Maybe others can provide some insight.

I can put the 1" group in perspective to my 6.5 Creedmoor rifle. Let's assume my common 8,000' Density Altitude conditions. Also assume (ahem) that I point the rifle perfectly and break the shots perfectly. And that every bullet is perfect in design & construction -- so that all bullets fly exactly where they are pointed.

So now we're theoretically down to only two things that can mess up impact -- wind calls and muzzle velocity variation.

Ballistics charts state that for every one foot-per-second change in muzzle velocity, my bullets impact higher or lower by .2 inches. So a 1" group requires MV variation of no more than 5 fps. This is possible, but it requires really careful ammo loading.

Ballistics charts state that for every one mile-per-hour change in cross winds, my bullets impact left or right by 4.9 inches. So a 1" group requires wind calls to be correct within .2 miles per hour.

All this precision just boggles the mind. But sooner or later, someone will likely produce even smaller groups.

Excellent

Utterly amazing!!! Congratulations to him on that extraordinary feat of marksmanship skill!

It's not just marksmanship skills; it's actually much more than that. This is the product of many skills and total attention to detail.

This is the best example of what I frequently refer to as the rifle system, at the fine edge.

Rifle.
Scope.
Rests.
Handloads.
Bullet.
Marksmanship.

quote:

Originally posted by NikonUser:
It's not just marksmanship skills; it's actually much more than that. This is the product of many skills and total attention to detail.

This is the best example of what I frequently refer to as the rifle system, at the fine edge.

Rifle.
Scope.
Rests.
Handloads.
Bullet.
Marksmanship.

Bench rest is mostly about reading wind, a good rifle, and load development. And while that guy shot an impressive group, it's not nearly as impressive to me as somebody who cleans a PRS stage from multiple shooting positions and distances.

I always refrain from comparing one shooting discipline to another and then ascribing a value to one versus the other.

I'm old enough to understand there are specific difficulties in each discipline and ranking them is futile, at best.

So while I don't necessarily disagree with you, I also don't necessarily agree and I say they are both great. There is plenty of room to applaud and praise both.

quote:

Originally posted by NikonUser:
There is plenty of room to applaud and praise both.

It's too easy to point out why one discipline demands skillsets, experience, or equipment that isn't emphasized in another discipline. Too often, we tend to say our own turf is the bestest and mostest badass.

Take car racing, for instance. The winner of a given race or series is the top of that heap. But how can we compare winners of Indy, Dakar, Nascar, Forumula 1, drag racing, or Sprint Car racing? The winners all drive cars.....

PRS competition requires elements of movement (person, rifle, & targets) that isn't there in bench rest. But the PRS competitor doesn't have to shoot .1 MOA groups to win, either.

Bench rest isn't my game, at this time of my life. Maybe someday, maybe not. However, I completely understand that lessons learned in bench rest shooting have contributed to the high performance levels of my own PRS-type gear.

quote:

Originally posted by fritz:

quote:

Originally posted by NikonUser:
There is plenty of room to applaud and praise both.

It's too easy to point out why one discipline demands skillsets, experience, or equipment that isn't emphasized in another discipline. Too often, we tend to say our own turf is the bestest and mostest badass.

Take car racing, for instance. The winner of a given race or series is the top of that heap. But how can we compare winners of Indy, Dakar, Nascar, Forumula 1, drag racing, or Sprint Car racing? The winners all drive cars.....

PRS competition requires elements of movement (person, rifle, & targets) that isn't there in bench rest. But the PRS competitor doesn't have to shoot .1 MOA groups to win, either.

Bench rest isn't my game, at this time of my life. Maybe someday, maybe not. However, I completely understand that lessons learned in bench rest shooting have contributed to the high performance levels of my own PRS-type gear.

well said Fritz!

quote:

Originally posted by hrcjon:
This seems like an incredible accomplishment. I'm wondering how close to a possible minimum it might be.

See, this is where we get into that whole can of worms about one amazing group vs. consistent, repeatable results.

This level of accuracy is pretty obviously way beyond what any combination of shooter and this type of rifle is capable of doing consistently in this type of competition - otherwise, it wouldn't be a world record by a significant margin.

If we assume that the rifle and the ammo and the shooter are all perfect, then you can do a pretty good job of modeling group sizes using probability theory. Basically, you assign a probability distribution to the area of the target, where there's some probability the bullet hits near the center of the target, and the probability goes down as you move away from the center.

At that point, your group size is basically down to luck... did all the dice land right so that where each shot landed in the probability distribution is right next to all the other shots. Usually they don't. Occasionally they do.

You can modify the parameters on the probability distribution so that, say, five-round groups average something like .25 MOA, and only one out of every 100 groups is worse than .5 MOA, and only one out of every thousand groups is better than .1 MOA.

The group size variation will be smaller the more shots there are in the group. This is an oversimplification, but let's say with our perfect setup, each shot has a 20% chance of being inside the .1 MOA center of the target. To get a 3-shot group with all the shots in that circle, the probability is .2 * .2 * .2 = .008. That's 0.8%, 1 out of every 125 groups. To get a 5-shot group with all the shots in that circle, the probability is .2 * .2 * .2 * .2 * .2 = .00032. That's 0.032%, 1 out of every 3,125 groups.

That's why a lot of internet folks don't take bughole 3-shot groups seriously. If you shoot enough, you can get a good 3-shot group out of something that patterns like a shotgun. Groups with more shots, or firing multiple groups and showing them all without picking and choosing the best and discarding the worst, is a much better measure of shooter skill and rifle accuracy. I used to be on a shooting forum where the rule was, if you wanted to post a group, it had to either be a 10-shot group, or at least five, 5-shot groups on one piece of paper.

It would be pretty easy to write a little computer program to demonstrate this. Maybe I'll give it a shot some time.

quote:

Originally posted by hrcjon:
Is there some form of long range shooting that is basically without technical rules so that people use 200lb steel slabs and silly stiff barrels and some kind of electronic ignition actions that shows what the lower limit might actually be? Sorry if this is easily known.

I think you're looking for "Unlimited Class" benchrest. It's shot at closer ranges, but as the name suggests, the rules are pretty permissive, and the guns don't even really look like guns anymore. They're just a giant barrel clamped in a huge metal sled with mechanical adjustments for aiming.

http://bulletin.accurateshoote...pitome-of-precision/

The article has pictures of a couple of the guns, a link to a video about them, and a picture of a 100-yard 5-shot group where the "group" is just one hole perfectly centered in the bullseye.

Thank you for the link on rail guns. I knew they existed but I didn't know that they didn't go 'long'.
I'm 100% with you that this type of long range record group is really a statistical distribution. You of course have to get your mean on every element in the hunt (that's the real work) but then you have to get 'lucky'. And I don't mean that in any negative way.

quote:

Originally posted by fritz:
Bench rest isn't my game, at this time of my life. Maybe someday, maybe not. However, I completely understand that lessons learned in bench rest shooting have contributed to the high performance levels of my own PRS-type gear.

Benchrest is not my game either. But I certainly pay attention to records like this, what caliber. Believe there has been three records set with the 6BRA this year. I've been shooting a 6MM Dasher for quite awhile, 6BR before that. The Dasher was developed by a couple Benchrest shooters in 1998. No doubt there's magic in that little 6BR case and its variants. Three buddies around me had jelrod1 chamber them 6BRA's, all shoot amazingly well. Always good seeing this stuff first hand, mag feeding.... 6BRA is very efficient cartridge, same velocity as the Dasher with about a grain less of powder. Should get few hundred more rounds of barrel life. When my two Dasher barrels die, decision time. I'll need new brass anyway, can use my Dasher dies. 6BRA uses a Dasher seater, chuck my FL sizer in a lathe and take .080 off the bottom. 6BRA being a Ackley, uses the shoulder to headspace 6BR brass. Easy load and shoot fireform. Easier then the false shoulder fire forming business of the Dasher.

I commonly run into a rail gun Benchrest shooter and his son at my local range, known them for 3yrs. Shot their rifles a few times, a light fart will set off their triggers. His son holds a couple records with his 6PPC at 100 and 200yds. Load tuning is their world. They load at the range. I use his method to tune my loads.

quote:

Load tuning is their world. They load at the range.

Now that it SERIOUS.

quote:

Originally posted by fritz:
So a 1" group requires wind calls to be correct within .2 miles per hour.

And the luck that the wind doesn’t suddenly vary unexpectedly by more than that. I have no idea what the usual conditions are at the range where that group was achieved, but where I shoot when the wind starts blowing, it sometimes varies wildly in speed and direction from second to second. (And no, that’s not the reason I can’t shoot 0.1 MOA groups. )

No matter how skilled a shooter is and how good his gear is, not having bad luck in the middle of a string is also vital for records like these.