How many in a group size??

How's about this for some rules:

5 consecutive days, 10 shots per day shot at 300 M on an ISU target (unless your locale precludes the use of one due to difficulty sourcing a supply same - like Otokiak and I would have) . Unlimited sighters on day 1 prior to commencement of first 10 shot string. No sighters after you start shooting for score on day 1 (that means no sighting shots on days 2-5). No cleaning of the rifle once the official string has started. Ammo must be loaded during the same loading session and stored in a MTM-50 or similar container (50 shot string ammo seperated from sighting ammo). Once the string has started you can only have the MTM-50 box at your shooting position. Must have a spotter to confirm compliance with the rules. You may have your own spotting scope on your bench along with notebook and writing implements. No Kestrels or wind flags (flags are only acceptable if they are fixed in position by the operating authority of the shooting range). Groups can be fired from bipods or other front rests so long as the front rest is not fixed to the rifle (exception for Harris/Parker Hale/Sinclair/Versapod etc bipods). Use of a read sandbag is permitted. "Lead Sled" or other weighted bench rests meant to mitigate recoil are prohibited. Any optics are permitted as are iron sights of any description. Any caliber is permitted. Group size will be measured by the greatest diameter method (outside to outside of the extreme opposed bullet holes with caliber subtracted). All entries will supply photographic evidence of group size with a scale (ruler, tape measure etc) measuring imperial units included in the photo. Group size should be measured using a dial or digital caliper reading to the thousandth ( .001" ) of an inch. Caliper should be in the photo measuring the extreme outside of the group. If no caliper is present then groups can be measured with a ruler or tape measure and rounded up to the nearest visible graduation (example, if your group is between 5 and 15/32nds of an inch and 5 1/2 inch then you must round up to 5 1/2" or buy a caliper).

Cheating in any fashion is punishable by taunting and a rotten fish sent to you in the mail.

That was more rules than I had intended. That often happens.

Sounds like a damned good test of man and machine and fun to boot.
 
I'd be down for this :D
Do we have a general outline of the rules? eg. calibers allowed ect ect

I'm interested to try with my my .338LM TRG-42 :p Ive been working on some shorter range loads as the BT's don't seem to stabilize as well withing 300 yards or so.
 
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The only rifle I have ever heard of with a 50 shot accuracy guarantee was the H&K PSG1. The rifles accuracy standard is (was) to shoot 3 inch 50 shot groups at 300 metres. Not too impressive by today's standards until you consider that this was intended to happen at a high rate of fire (using 20 round mags from the G3)....All this in the mid 1970's following the Munich massacre.

The idea of wasting 50 300gr .338 SMKs is more than I could take.....Unless the target was far enough away!

My old 10' twist 223 was never a bug holer, but I once put 20 rounds into one inch at 200 yards as fast as I could shoot and reload the mag box.....While I was unimpressed by the rifles ultimate accuracy I was impressed by its consistency.....

OK! It has a new 8 twist barrel!:redface:
 
Yes you can say only one round counts and sometimes that is true. But it has to hit the middle of the target and this is what we are talking about here.

Ugly, I think you have it. Only thing I would change is no other firing of the rifle once you start, ie you are not allowed to shoot a different target or range and then go shoot the record target, to emphasize the no sighters rule.

I think we also need some sort of score & group size formula because hitting what you want is really more important in the real world that group size. You have to read wind and deal with conditions.

This will open some eyes!!
 
X-fan said:
The only rifle I have ever heard of with a 50 shot accuracy guarantee was the H&K PSG1. The rifles accuracy standard is (was) to shoot 3 inch 50 shot groups at 300 metres. Not too impressive by today's standards until you consider that this was intended to happen at a high rate of fire (using 20 round mags from the G3)....All this in the mid 1970's following the Munich massacre.
Click to expand...

You don't find 50 into 1MOA at 300 impressive for a 30 cal semi?
 
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Ian Robertson said:
Ugly, I think you have it. Only thing I would change is no other firing of the rifle once you start, ie you are not allowed to shoot a different target or range and then go shoot the record target, to emphasize the no sighters rule.

I think we also need some sort of score & group size formula!!
Click to expand...

How about two scores - one for group size and another for the distance from group center to target center? I kind of took for granted that groups would be shot with the center of the bull as the POI. I also like the "no other shots once 5 Day String has been started.

If we get a few people into this it should produce some interesting discussion!
 
carbonrod said:
You don't find 50 into 1MOA at 300 impressive for a 30 cal semi?
Click to expand...

Yes I do think it impressive...Thought my post said that....guess not!:redface:

1 moa from a (precision bolt action) at 300 meters is nothing special.
Add a battle proven semi auto and 50 shot groups and it certainly is impressive!

Factor in late 1970's technology and the accuracy was (and still is) nothing short of astounding!
 
Ian Robertson said:
Maybe add some extra size for every point dropped?
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How about distance from point of aim (or Desired Point of Impact)?

Theoretically a 6" group could be 3 inches from Point Of Aim.....
Conversely a 1/2" group could be 20 inches from Point Of Aim.:eek:

This tests rifle, ammunition, as well as the shooters ability to hit a specified target size at a specified distance.

Ten rounds will do the deed.
 
Ring Diameter Color
10 100 mm (±0.5 mm ) Black
9 200 mm (±1.0 mm ) Black
8 300 mm (±1.0 mm ) Black
7 400 mm (±3.0 mm ) Black
6 500 mm (±3.0 mm ) Black
5 600 mm (±3.0 mm ) Black
4 700 mm (±3.0 mm ) White
3 800 mm (±3.0 mm ) White
2 900 mm (±3.0 mm ) White
1 1000 mm (±3.0 mm ) White
 
Probably the best test of rifle precision is the old "string measure" method. This is especially applicable if the first shot is taken as the established point of impact.
String measure is the total distance of all shots from the center of the target or from the established point of impact. The use of "string measure" can eliminate some of the failures of the simple group diameter and score methods.
If shooting for score, a flyer resulting in a dropped point is there for the rest of the string and the score is reduced by that point. If it happened that this was the first shot and all others were tens, we don't get a true measure of the rifle's precision capability.
In the case of a measured group, the flyer's effect can be minimized by "filling in" so the group never gets any bigger but it won't get any smaller either.
So in the case of a target fired for score, the flyer turns a 500 into a 499 and a 499 with one flyer and the other forty nine clustered tightly in the centre is beaten by the 500 where all fifty shots nicked the ten ring.
Likewise, the group with forty nine in one inch and a flyer one inch out is, at best, a two inch group and is beaten by the group where all fifty are randomly scattered over 1.9 inches.
If the first group was scored by string measure, the distance of each shot from center would be added so a dead center shot is a zero. A thirty caliber just touching center is, roughly, .150 and so on. A flyer two inches out is there but it's effect on the final score can be minimized by the rest of the shots. In other words, you can compensate, with good shooting, for an errant shot rather than just avoiding another.
I have pointed out before the big differences between 5 shots for score and five shots for group. In five shots for score, all five shots have to be placed near enough to center to receive the top value. Once top value has been achieved, however, there is no reward for placing the shots even closer to center. In addition, if the first shot is errant, the point is gone and can't be retrieved.
In firing five shots for group, the first shot is a gimme ( I've found, if the first shot goes somewhere remote from where I expected, it's not likely I'm going to have a good day, mind you!) and it's only necessary to place the other shots precisely in the same place. You are, however, rewarded for better placement of those shots. A group with a thirty caliber in which the last four shots just touch the center of the first hole will measure
.308" while one in which the four shots overlap the center of the first by.025 inches will measure .258. Either of these groups will beat the group in which the first four shots go precisely through the same hole but one shot is .310" out.
Using string measure, the first group would score .608. The second would score .524 and the third would score .310. This if the center of the first shot was taken as the center from which the string was measured. So, the shooter would be rewarded for the four superb shots or penalized for four scattery shots. If the center was the pre-determined center of the target, then the distance of the group from that center would come into play and different groups would win depending on placement and orientation.
Beyond this, the statisticians could get into the act and the score could be the average distance from center or even the standard deviation from center. Then they could argue over which was the REAL measure of rifle/shooter competence. Regards, Bill.
 
Before I get too far into this please note I am a Target Rifle shooter, shooting an iron sighted .308 off my elbows with a jacket and sling.
Usualy when shooting long range and short range (600 yards and under) I always figure rifle/shooter/ammo combination is at it best when the vertical group is small. How wide the group is depends on how well the shooter can read the wind and make the proper sight adjustments. Loosing points at long range because of the wind is one thing, but if you are making good wind calls and loosing points the elevation problems:bangHead::bangHead::bangHead:
 
Ian Robertson said:
Ring Diameter Color
10 100 mm (±0.5 mm ) Black
9 200 mm (±1.0 mm ) Black
8 300 mm (±1.0 mm ) Black
7 400 mm (±3.0 mm ) Black
6 500 mm (±3.0 mm ) Black
5 600 mm (±3.0 mm ) Black
4 700 mm (±3.0 mm ) White
3 800 mm (±3.0 mm ) White
2 900 mm (±3.0 mm ) White
1 1000 mm (±3.0 mm ) White
Click to expand...

I just made this target in Illustrator and saved it as an Adobe PDF file (Acrobat Reader). Kinko's could probably print them up for a few bucks each. Anyone who wants a copy PM me.

B
 
Considering that we want to hit the middle of the target, if you measure the distance to all shots and add them up would be about the most accurate way to pick a winner. I would imagine that electronic target systems should be able to do this. The final shoot off in Olympic type, for example, is essentially scored this way I believe.
 
I have often wanted to test a rifle or test ammo (factory and handloads). Have shot groups many, many times on the range behind the house (200 yards) . I have a good bench set up, so shooting groups on a fairly consistent basis has been easy.

The challenge has been figuring out what the groups mean.

I usually install a 24X or 36X scope on whatever rifle I want to test. A Mini14 looks kind a strange with a 36X scope perched on top.

My firing point is indoors, so barrel heat destroys a sight picture after about 3 shots. So I have fans to blow across the barrel. Outdoors, on a dead calm day (perfect for testing) the same problem occurs. I have a 120volt inverter to run off the car battery (parked behind the firing point) and a fan to keep a clear sight picture. In the picture below you can see the fan on an outdoor firing point.

Having watched thousands of groups form, I can say that many a great looking 5 shot group became a ho-hum group by shot 10. When testing target rifles and target ammo, I use only 10 shot groups.

My procedure is to fire 5 fouling shots to warm the rifle and to help me “get into the groove”. Some rifles shoot these 5 shots perfectly. Others need the 5 shots to settle down. This would be a good thing to know about your rifle.

Flyers can go into the group as well out of the group. For this reason I think 5 shot groups to be a poor indicator. When I find a load or lot number of ammo that grouped well in a test, I go back and shoot a couple more groups, to make sure the first 10 shot group was not a fluke.

I have also tested a lot of hunting rifles. Some will shoot a good 3 shot group and then go to hell. Others will shoot 5. Only a few will shoot 10. This has to do with bedding and maybe barrel heat treating for stress relief.

If I have a hunting rifle that will hold zero and shoot a good 3 shot cold barrel group, every time, then what more do I need??

P7180005.jpg
 
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