I will rephrase - 3 round groups mean very little statistically, and nothing to me personally. Why? Because the greater your sample size, the closer your measurement will be to the actual value. You could shoot 1 round ‘groups’ and infer from the data that you have a perfect laser rifle, but that would obviously be a highly inaccurate statement. A 3 shot group is much better than a 1 shot group but still does not hold much statistical significance. Of course it is not practical to shoot 100+ round groups, so we need to stick to more practical group sizes.
You are correct, and it is unfortunate that 3 round groups are very common amongst the shooting industry – especially by entities with an interest in showing you a rifle in its most favorable (and biased light). There are several reasons for this:
Manufacturers obviously want you to think their product is as accurate as possible; the same rifle might reliably produce 1/2 MOA 3 round groups or 1 MOA 10 round groups – which sounds better?
Magazines make good revenue from advertising. How likely would a rifle manufacturer be to advertize in a magazine that reviews their rifle as 1/2 MOA (3 round groups); how likely would they be to advertise in a magazine reviewing their rifle as a 1 MOA rifle (10 shot groups)? How often do you read a scathing review about a rifle in a magazine?
Just as a casino knows you have a better chance of holding a single Ace in your hand than you do of holding 3 aces, a rifle company with an accuracy guarantees knows that you have a better chance of producing a 3 round group of any given size than a 5 round group of that same size.
Granted, a rifle may shoot less accurately if the barrel is hotter, but who said not to let the barrel cool down between shots? The statistical word for “fliers” would be “outliers”.
“If you can’t drop a deer with one shot you won’t with 3 shots” – this idea is 100% correct but irrelevant to the statistics. How many shots you shoot before measuring your group has nothing to do with how many shots you may need to take while hunting. What the number of shots in your group does tell you is how confident you can be that you could shoot that precisely again.
Well that was kinda long... I guess I could have just said that 3 rounds give less confidence that you can reproduce your results than a group shot with more shots. If you like 3 round groups shoot more of them and combine them so that two 3 round groups equal a 6 round group.
Precision guys never get any love in a black rifle or hunting forum
After reading this thread I miss my RFB... but it is with a better owner now, one who shoots it the way it was meant to be shot and not like a precision rifle