And you thought accuracy claims with 5-shot groups were suspect

[wally]

Here is an article using 2-shot "groups" with a straight face.

http://dailycaller.com/2016/10/11/gun-test-savage-arms-10-ba-stealth-in-308-winchester/

Its got some nice photos of the new Savage 10 BA Stealth "Chassis Rifle"

MSRP a couple hundred less than the Ruger Precision Rifle Gen2, about the same as the Gen1. Straight away I'd lean toward the Ruger (neglecting the fact that I'd already bought one) because it uses a "standard" .308 P-mag which are easy to find and have a lot of capacity options.

Also the RPR accepts M-14 mags, I've verified fit, but not function as off a bi-pod I prefer the 10 round Pmags.

 

[M1key]

Maybe with a drilling or double rifle...

M

 

[Sembob]

The Savage also offers a couple of long actions as well. 300 win and 338 Lapua.

 

[Bart B.]

I think that rifle shoots the Hornady ammo about 1.5" at 200 yards as shot; maybe bigger. The odds of all three group centers being at the same place relative to point of aim is slim to none. Too bad the targets weren't pictured.

Ne'er the less, that's pretty good for a commercial rifle. I don't judge accuracy by smallest few-shot groups fired. They don't happen every time one's shot. They do happen as often as the largest few-shot groups.

 

[bfoosh006]

Clearly his testing for group size is twice as accurate as just one round ....

( Yes, I realize that would be virtually impossible... but my comment is in "stride" with the article... )

 

[wally]

Clearly his testing for group size is twice as accurate as just one round ....

Actually a "1-shot" group fired from a clean, cold barrel measured against the point of aim can be a useful test for a hunting rifle. As would be a second quick follow-up shot, and one done after these two when the barrel has had plenty of time to cool.

 

[agtman]

Throwing the big ol' B.S. flag on this one ... Maybe another for flagrancy.

Your first shot from a clean, cold barrel is your "cold-bore" shot. It will impact differently, even if just by a little, than your following shots.

That's why firing 3-shots only establishes a bare minimum for concluding that you have a point of aim on paper with that rifle and that load, preferably at 100-yds.

Thereafter, you need to fire a minimum of 5-shots to establish one or more consistent groups, from which to make sighting adjustments (elevation & windage), or if doing accuracy testing with reloads.

If you think you've found two or three loads your rifle likes, whether they're factory or handloads, you should shoot a 10- shot group of each as a final vetting.

 

[wally]

Throwing the big ol' B.S. flag on this one ... Maybe another for flagrancy.

Your first shot from a clean, cold barrel is your "cold-bore" shot. It will impact differently, even if just by a little, than your following shots.

My point is if you are primarily a hunter, You sight in your rifle at the start of a season, clean it and are "ready to hunt" This 1-shot or its 3-shot variation test tells you what is most important if you are really ready or not. If there is a big shift between cold & clean and the others it is a problem! Hunters don't really care about group size, they care about POA vs. POI as more than about a 5" deviation at the range of interest is unlikely to result in a humane kill.


Maybe current hunting doctrine is to not clean your rifle after sighting in at the start of a season -- I'm not much of a hunter but when I did hunt twice a year with my first wife's family, a "clean bore" first shot was the norm -- but that was like 30+ years ago.

 

[MachIVshooter]

Your first shot from a clean, cold barrel is your "cold-bore" shot. It will impact differently, even if just by a little, than your following shots.

That's the point wally was making. With a hunting rifle, it doesn't matter if it starts stringing and making large groups as it warms up, as long as your cold bore shot is on target. Likewise, it matters not if the thing can shoot 1/2 MOA at 500 yards if the cold bore shot is not on target.

I also agree that 3 shot groups are fine for sighting in. 5+ are necessary for accuracy claims.

 

[lysanderxiii]

Yeah, but....

Let's assume an extreme case of a rifle/shooter combination that has a group size of 12" at 100 yards.

If you shoot one round and it hits the bullseye dead center, where is the most likely place the second round will go? Six inches to the right or left? Or, twelve inches to the right or left?

In order to verify the POA and POI are coincident, you have to shoot a reasonable group.

 

[Art Eatman]

What has worked for me since a half-century back: First, I check out the rifle's capability with several five-shot groups. I'll do whatever is needed to reliably get sub-MOA groups. Tweak the bedding, maybe; play with handload combinations.

Okay, let's say I change the scope. All I need to do is sight it in. For that, I want the center of a three-shot group to be two inches high at 100 yards.

After that, a single shot is enough to check that nothing has changed--although I'll shoot more, just to test myself.

Color me lucky if you want to: My two pet rifles shoot into the same group sizes whether or not the first shot is from a clean cold barrel. Most of the time, my cleaning of a barrel is via WD40 on a patch for a couple of swipes, followed by a patch with a little RemOil sprayed on it, for a couple of swipes. IOW, minimal oiliness against rust; nearly dry.

 

[entropy]

I've always used three-shot groups for sighting in. I usually put five or ten on a new target after to verify.

 

[MachIVshooter]

Yeah, but....

Let's assume an extreme case of a rifle/shooter combination that has a group size of 12" at 100 yards.

If you shoot one round and it hits the bullseye dead center, where is the most likely place the second round will go? Six inches to the right or left? Or, twelve inches to the right or left?

In order to verify the POA and POI are coincident, you have to shoot a reasonable group.

To that I submit that if it hits bullseye dead center every time on a cold bore shot, that's what's most important to a hunter.

Of course, you're not gonna see 12" 100 yard groups unless you're using the wrong diameter bullets or the scope has come loose (or you're shooting a mini 14). Which brings us back to the point; for a hunter, whether the rifle is sub MOA or 2 MOA, if the cold bore shot doesn't hit POA within a reasonable margin, the capability or lack thereof to produce tidy little groups from the bench doesn't matter. No hunter I've ever met throws his first shot and hopes the critter will stick around for the accurate follow up "warm bore" shot

 

[Bart B.]

Rifle making companies could fix the cold bore to hot bore bullet impact change for $25 to $50 per rifle. That's enough to cover one extra machining step to face the receiver square with its barrel tenon thread axis.

If they did it with a stop-mill that went against the bolt face, all receivers would then have the same distance from closed bolt face to receiver face.

 

[Corn-Picker]

One other thing hunters should consider is the error in where you aimed vs where you should have aimed. Hitting the center of a paper plate at 100 yards is relatively easy. Hitting the center of a paper plate that's hidden inside of a paper grocery bag is less easy. The latter situation is more analagous to what it's like when shooting at the lungs of a deer.

 

[Casefull]

After the fouling shot. Shoot one cold bore shot each day for 3 days. That is where your sights need to be adjusted to if you are hunting with the rifle. All the other theories about multi shot groups have zero application as the rest is target shooting. If you are a military sniper then group size is obviously important if things get hot and busy in combat. Most guys shooting 1 inch groups off a bench or with bipod/some forearm support would have trouble hitting a deer offhand at 100 yds. What matters is what the rifle and the shooter can do when the instant opportunity presents itself. I am sure I am in the minority here as most on the forum seem to be target guys rather than hunters.

 

[Orcon]

I've started shooting incredibly small groups recently. I take my rifle out and chamber a special hand loaded cartridge. BANG, BANG, BANG, BANG, BANG, BANG, BANG, BANG, BANG, I yell. Then I pull the trigger. I only do this when I'm wearing 5.11 and have a shemagh handy. I've been shooting 1000 yard one hole groups lately, I am so sniper.

 

[Bart B.]

agtman, I agree the second shot will go somewhere away from the first one.

What direction does the second shot usually go from the first one from a clean barrel?

Is that second shot always the same distance away from the first one?

 

[barnbwt]

This is why you need more than two shots . Yeah, two shots is pretty lame. Either really lazy shooter (who's too lazy to shoot more than twice unless it's some monster magnum?) or a really bad shooter trying to get a decent looking photo for the article. The reason for more shots is to minimize the possibility this was the fourth or fifth grouping attempt that finally got the bullets close together by random chance (gun or shooter)

TCB

 

[agtman]

I've started shooting incredibly small groups recently. I take my rifle out and chamber a special hand loaded cartridge. BANG, BANG, BANG, BANG, BANG, BANG, BANG, BANG, BANG, I yell. Then I pull the trigger. I only do this when I'm wearing 5.11 and have a shemagh handy. I've been shooting 1000 yard one hole groups lately, I am so sniper.

LOL, ... almost spit up my morning Starbucks reading that one. Funny stuff.

 

[agtman]

agtman, I agree the second shot will go somewhere away from the first one. What direction does the second shot usually go from the first one from a clean barrel?

Depends on which bolt rifle or SPR, I'm shooting.

On my WOA 18" SPR (shot suppressed), the second round after the clean cold-bore (CCB) first round will impact about .50" right and low, beginning a sub-MOA cluster with the following four shots, or a vetted group, if I shoot five shot (for a total of six rounds fired).

Is that second shot always the same distance away from the first one?

On this SPR, pretty much, when shooting the match load it prefers. Admittedly, there will be variation. I recall once after shooting the CCB shot, the next four shots hit right and low by about two inches, but those four shots created something like a .333" cluster ... I'm was pretty sure that deviation from the POI of the first CCB shot was my fault, but the temps that day were also 40-degrees different than when it was zero-ed the day before, and the match ammo was temp-sensitive.

 

[Sheepdog1968]

I tend not to shoot much better than 2 MOA on average with my rifles. I base this on 10 shot groups. I can't imagine I'd even be that good in filed conditions hunting. If I am coarse zero adjusting a new scope I will use single shots to get me within two inches of bullseye. After that I will usually start to,use 5 shot groups to refine it further.

 

[lysanderxiii]

To that I submit that if it hits bullseye dead center every time on a cold bore shot, that's what's most important to a hunter.

Of course, you're not gonna see 12" 100 yard groups unless you're using the wrong diameter bullets or the scope has come loose (or you're shooting a mini 14). Which brings us back to the point; for a hunter, whether the rifle is sub MOA or 2 MOA, if the cold bore shot doesn't hit POA within a reasonable margin, the capability or lack thereof to produce tidy little groups from the bench doesn't matter. No hunter I've ever met throws his first shot and hopes the critter will stick around for the accurate follow up "warm bore" shot

1) Your bold implies that you shot more that one round.....and probably more that two.

2) I stated "Rifle/shooter combination is 12 MOA", or are you saying that everyone that goes hunting has the skill to make a snap shot with the ability to remove their own aiming error from the equation and their "probable circular error" is the same as the gun's inherent accuracy?

As I prefaced, the example was an extreme case, but even with a 2 MOA rifle shot from a bench under calm, measured, unhurried conditions, after a few fouling shots, if the first shot is a bullseye, where is the second shot going to be? are you going to assume that the first (and only) shot was in the center of the bell curve or at one of the ends?