If Gary goes out and purchases a rifle because Larry and Steve like theirs.

Is there any chance at all that all three rifles till shoot very similarly with the same ammo?

Off the shelf rifles ,not special order elite custom modified jobs.

Or

Is it going to be a spin of the giant wheel of chance?
As
To what ammo will be optimal out of each gun?

I think factory tolerances will probably be close enough that three factory rifles coming off the same line will have very similar chamber dimensions and barrels and will therefore shoot pretty similarly with the same ammo (that was also manufactured with pretty decent tolerances.)

They’ll all kill a deer the same, when you get thousandths of an inch then there will probably be some differences.

Definately not the case with .22 LR rifles. Luck of the draw with them in most cases.

So if the first guy takes the time to try a dozen different makers of ammo and five different weights.

He can tell the others and they can come close to similar performance.

If the other shooters possess the same abilities.

I have 3 different AR15s 2 are the same barrel length and rifling twist. The 3 is an AR pistol.

The 2 carbines shoot the same about 2” at 100 yds with iron sights if I’m having a good day. I have a scope i can swap between them, they both are within an 1 - 1 1/2” (if I use a sling). Smaller if I use a bipod.

DPMS and Bushmaster purchased 5 years apart. Both new and no mag dumping etc.

Definitely maybe.

Not a bad place to start however those receivers and barrels came out of a bin at different times, perhaps built by a variety of shifts.

Really depends on the demands of the rifles mission.
In a regular hunting rifle or defensive AR for example, any difference is likely to be very small either unnoticeable or entirely inconsequential
In a precision rifle with a very high accuracy and consistency expectation, whole different story.

Depends on the platform and the consistency of the manufacturer.

Tony.

I would think they would be similar, not necessarily accurate or precise, that would depend on the particular specifications of the build.

The factual answer is "it depends". I would think with modern technology the preferences would be close, but I've found two exact models can sometimes give slightly different chronograph averages with the same loading. My Remchester made in March of 2023 could have slightly different tolerances than your Remchester made in November of 2023.

quote:

Originally posted by bendable:
If Gary goes out and purchases a rifle because Larry and Steve like theirs.

Is there any chance at all that all three rifles till shoot very similarly with the same ammo?

Off the shelf rifles ,not special order elite custom modified jobs.

Or

Is it going to be a spin of the giant wheel of chance?
As
To what ammo will be optimal out of each gun?

I would suspect that it would depend on how much time passed between the production of said rifles and the maintenance that had been done on the machines that cut (especially) the barrels.
For instance if the cutters that had been used were needing maintenance or near the end of life for rifles of Larry and Steve, but Gary’s rifle was produced by equipment that had been freshly calibrated and sharpened cutters would likely do better providing the 3 men’s skills were equal.
Just my humble opinion.

It would really depend on manufacturer, and their tolerances and quality, but in general, no.

Here’s an overly simplistic thought experiment. Let's say a manufacturer has two machines, A and B to make barrels, with tolerances of +/- 5. Machine A turns out barrels +5 and B turns out barrels -5. The same manufacturer has two other machines, A and B making bolts, with the same tolerances, and once again A is 5 long and B is 5 short.

Now, if you assemble a rifle with an A bolt and A barrel, fit will be ideal. Same thing with a B-B bolt and barrel. But, if you assemble a rifle with a bolt off of machine A and a barrel off of B, it will still be within spec, but you can easily imagine that performance would vary. Similarly with a B-A rifle.

Bendable -

Let’s assume Gary, Larry and Steve all like exactly the same brand, model and even get lucky enough to get three rifles each within 1,000 pieces of each other (extremely unlikely by the way).
What we are getting into is what used to be called “Statistical Process Control”. It involved a particular part being built within a specified tolerance. As an example - virtually all AR lower receivers are built to such a close tolerance that they will be compatible with every brand upper receiver. The parts aren’t prefect, but they are so close that they fit where they need to fit. How close is close?

Well a human hair averages .003”. They might be .0035, maybe .004” . Thin might be .002”. The AR receivers might be within .0002”, ten times finer than a human hair. They might be even closer than that. The tolerance for a particular fit might be .0001”. That would mean a target size for a hole might be .2500” - plus or minus .0001” Acceptable sizes would then be .24999 up to .2501”. More than that would be a rejected part. ALL parts have specified tolerances. Some are bigger, some maybe smaller.

Why not make them all “perfect” (ie .2500”} ? Costs are the reason. If all had to be perfect then the reject rate would go up and costs would rise. Also the equipment to manufacture the part would be more expensive (cost increase) quality of labor would go up, etc. etc. We can build the perfect rifle, we just can’t afford it.

So, how does this affect the three rifles in question? When production is started the machines are set to make the (almost) perfect part. After 100 parts the piece coming off the machine are a little looser, but still within tolerance. 500 parts? A little looser. A thousand parts and there are a few coming through out of tolerance. Quality control is by the way watching this “loosening” very closely. (That’s the statically process control part of the process) Admin. might have a standing policy of “50 rejects of every 1,000 parts and it’s time to reset the machines”.

With all this discussion we are talking about ONE part. ALL the parts in the AR have these tolerances. Now you want to ASSEMBLE a rifle. Some of the parts for our one rifle are perfect. Some are really close to perfect. Some are good. Some not so good. Larry’s rifle was built a month later, after half the machines were reset. Steve’s rifle was built the next week, after more machines were reset, but with some other, older parts in the batch. You can begin to see why they don’t shoot the same.

The more parts in an item, the more potential variation that can be introduced.

An interesting comparison might be three consecutively numbered rifles. They might be pretty close. Anything else is just a crapshoot.

The only factory AR15 I have ever bought was a Ruger AR556 back in 2017…it will shoot 3-5” at 100 yards (which is good enough to ring an 8” steel target at 100 yards for fun)…later on that year I built my first AR (just because I wanted to find out if I could)…my local range has members who would aid in supplying tools needed…I preceded to take advantage and built my first AR using an AERO lower, Ballistic Advantage 18” Hanson SS cross pinned barrel…AERO upper with the integrated barrel nut and everything else was Ballistic Advantage or AERO (however I did choose a ToolCraft BCG and RockRiver National Match 4# trigger)…this rifle has averaged minus 1 1/2” groups at 100 yards with range ammo (winning me several lunches at the local Burger King)…all that being said…I have since purchased three Bear Creek Arsenal uppers…the first was before they started offering the hammer forged barrels…it was the just pretty much normal AR accuracy) the other two (side charging with th HF barrels went past their price point…coming close to my Aero BA build’s accuracy…this just reinforces my opinion that sometimes it’s the little things that make a difference…your mileage may vary

quote:

Originally posted by got2hav1:
Definately not the case with .22 LR rifles. Luck of the draw with them in most cases.

This for sure...I keep a list of which ammo goes with which .22. I have identical Henrys and Rugers that all prefer different ammo.

I don't think different brand AR's fits the original question. But in reflection on that issue it occurred to me that I do have 3 of the same rifles that are identical from a number of manufacturers. none purchased serial, but for sure they are the same mfg. and model. So for those I can say the differences in performance are exceptionally small. Easily within bendable's "very similarly" language. Full disclosure none of them are special order elite guns but all of them cost 4 figures but are regular production guns anyone can buy. The guns span a number of different mfg.(FN, Geissle, Sako, Tikka, DD, CZ) and types (both bolt and semi) and two different calibers.
I have no clue if my experience would apply to guns that cost way less like ruger americans or the mossberg budget lines.
all fwiw...

I believe that it’s likely all three are capable of the same level of accuracy. I do not believe that the exact same load will be the most accurate out of all three.

No rifles in any style or in any types or combinations shoot to the same poi, cheap or expensive, custom or factory, hand made or otherwise. Each rifle is its own creature. Why do you think fighter pilots' names on on the cockpit of each plane ? Those machines are all hand built with precision, and yet they are all different, though they share the exact same specs for a given model. Same with race cars, everything. Rifles are no different.

There are theories for this effect in physics and engineering dynamics for this behavior, it's interesting stuff, way over my head.

"No rifles in any style or in any types or combinations shoot to the same poi"
Of course I agree with you at some level of precision.
But the level of precision needed to show that difference is IMO way, way more than what the OP asked about "very similarly". I interpret that to mean within a reasonable level of precision as would be expected for that type of rifle. And I'm pretty sure production level rifles can do that. Otherwise is would be impossible for mfg. to offer things like the Tikka 1MOA guarantee. And you would be reading how PRS comptetators have to buy 3 rifles to find one that shoots well. I don't know anything about the reason military airplanes have assigned crews, but I doubt its because of material plane differences. I do know that in race cars and/or motorcycle racing series with backup cars/bikes when the original is wrecked the backup is used to the same lap times (or at least "very similar"). But neither of those are good examples of series produced simple production line goods like a modern rifle. And in those I'm pretty confident at least at a certain price point (and can speak personally for a decent sample) that the OP would find they are "very similar".

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