Thread: More 3 shot group fun!

Some time ago I bought a Bradley made 308 heavy target profile barrel off a forumite who I think shoots mainly F Class. Anyhoo this barrel didn't make the cut although his 3 shot groups didn't look too bad - certainly sub MOA at about 0.65" at 100 if I recall correctly. It's Savage threaded and since I had some Savage bits lying about (ex @Padox haha) it finally got put on a rifle.

Bought a packet of Hornardy 155 ELDMs. Set them up in some Lapua cases with the old standby of 46.0gn of 2208 (I made a few test rounds up to work up - just in case) This load delivered 2940 fps, so fairly snotty even from a 30" barrel.

I shot my normal 10 shot group at 100M, then moved back to the 300Y (274M) and shot the following 3 shot group for validation ( was 3 cause that's all I had left). Not too shabby eh - measures 19mm centre to centre?



Now just for shits and giggles I dare ya's to guess the size of the 100M 10 shot group . . .

Really nice!

Question. Do you think the one shot lower is the guns inherent accuracy? Or human ability to judge such a microscopically small required aiming point?

Aiming points are another poorly understood concept by many shooters. The guys shooting Double aperture sights can maintain sub 0.5 MOA holds, and that with a big round aiming point . . . . How, well the eye has a marvelous ability to "centre" the white space round or between a black or darker area. I was using a pretty good 24X scope to shoot that group, but could easily (and have done in the past) done it with 10X, the white target centre is the key. I just relax my eye and let it centre the reticle. The commonly held opinion of "aim small shoot small" by trying to put a reticle on a small dot is counter-productive and only works to a limited extent with young eyes.

So, the group is a poor representation of the rifles mechanical accuracy and my ability these days to maintain a consistent hold/follow through.

10 shot at 100 = 0mm all one hole

It's an impossibility to guess, But for what it's worth, I tend to find relatively speaking, that my hundred yards groups are slightly bigger on scale than my longer range ones. And its 10 shots where a number of other factors including human error are more likely to show.
So Ill say 27mm

1.5in

^^ @chainsaw - close

Here is the 100M group:


So yes, statistics in action, a much larger 100M group. It does tell me the rifle is shooting well, a Mean Radius of under 0.5 MOA is gonna cleanly kill deer to any distance, and a low 0.3 MR is going to get you most plates bar the 1/2 MOA size and at anything past 300-400M your wind call is likely more important than your absolute accuracy.

Your'e meant to be getting the .257R ready for our Longwoods trip, that I haven't mentioned yet.

Originally Posted by nor-west

Your'e meant to be getting the .257R ready for our Longwoods trip, that I haven't mentioned yet.

It is ready, raring to go.

Here is todays effort. We had an MOA challenge day. The challenge starts at 100M where one is attempting to put 5 shots into a 1.0 MOA "dot". Its a good bit harder than it looks. Here is my effort today with the 308, close but no cigar. I think this rifle should get to 5 shot 0.5 MOA groups with a little more discipline on my part.



Even though this 5 shot group ran a tad over 0.8 MOA we all had a tough day in a difficult wind with some of us (me included) not able to make a hit on the 1.0 MOA plate at 400Y and 600Y. In fact there was only one 0.5 MOA plate hit at 400 across about 10 shooters and none at 600.

Very nice @Tentman I really like the sound of the challenges your club puts on

Did you make an adjustment between your 10 and 5 rd 100m groups?


You should expect that 95% of your shots from this system will fall within around a .45MRAD circle due to dispersion, based on your 100m mean radius. It will be a little smaller or larger as a 10rd mean radius measurement isn't exactly precise. You should expect a group of any number of shots at 300m to have an extreme spread of anything up to 13.5cm purely due to dispersion, although most of them will be smaller. The ability to centre that on a target, or any wind error, ranging error, additional shooter errors off the flat range, etc are of course additional issues to deal with.



The 3 shot group at 300 of course tells you nothing informative.

Originally Posted by Tentman

Here is todays effort. We had an MOA challenge day. The challenge starts at 100M where one is attempting to put 5 shots into a 1.0 MOA "dot". Its a good bit harder than it looks. Here is my effort today with the 308, close but no cigar. I think this rifle should get to 5 shot 0.5 MOA groups with a little more discipline on my part.

Attachment 267234

Even though this 5 shot group ran a tad over 0.8 MOA we all had a tough day in a difficult wind with some of us (me included) not able to make a hit on the 1.0 MOA plate at 400Y and 600Y. In fact there was only one 0.5 MOA plate hit at 400 across about 10 shooters and none at 600.

In my view shooting at 0.5MOA plates is a bit of a waste of time - hit probability is well below 100% at any distance or conditions, making it a game of chance to a large degree. You can do everything perfectly and still be unlikely to hit. That isn't a good situation for learning.

Originally Posted by Tentman

Aiming points are another poorly understood concept by many shooters. The guys shooting Double aperture sights can maintain sub 0.5 MOA holds, and that with a big round aiming point . . . . How, well the eye has a marvelous ability to "centre" the white space round or between a black or darker area. I was using a pretty good 24X scope to shoot that group, but could easily (and have done in the past) done it with 10X, the white target centre is the key. I just relax my eye and let it centre the reticle. The commonly held opinion of "aim small shoot small" by trying to put a reticle on a small dot is counter-productive and only works to a limited extent with young eyes.

So, the group is a poor representation of the rifles mechanical accuracy and my ability these days to maintain a consistent hold/follow through.

On this note, My scope has a central dot. Since getting it ive shot really well. Even though it takes up a larger area of the target. Im wondering if its helping me centre on the bull better than a standard cross?