Rimfire accuracy...

[Tenntrapper]

I'm sure it would apply to centerfires as well, but for simplicity...let's keep it about rimfire rifles.
What makes one rifle more accurate than another...with everything else being equal?
Let's also just stick with bolt action for this...
Two rifles could come off the line one after the other, and could shoot different. I could understand a difference in say the first rifle...and the ten thousandth. Tooling wear, etc.
But even different manufacturers... generally speaking, why is CZ more accurate than say Marlin? Why are Annie's so accurate? What specifically is it about them that contributes to their accuracy? If it's the barrel, then why the (possible) difference in two consecutive rifles?
Just something I woke up curious about this morning. Any insight would be appreciated.
Thanks

 

[MUP]

Chamber reamer for a match chamber has something to do with it I'm sure. I've never encountered two factory consecutive serial # rifles where ones shoots great and the other terrible so I can't comment on that aspect. I do see the difference in CZ rifles that have a match barrel and those that do not tho firsthand. A tight match chamber appears to be a big factor.

 

[Iglow]

Aguila sub sonic hp LR ammo covers a lot of variation. There are so many factors I'd guess, humidity,wind, heat, cold,etc. For the shooter, blood pressure, frame of mind, skill, fitness.
You'd have to shoot thousands of rounds in different conditions with a range of ammo to chart and prove 1 rifle is more accurate than another.
But back to the Aguila, I use to shoot a lot from a bench in the back yard and that round shot noticeably better in every rifle and pistol I shot. I shot it against Eley, RWS and a bunch of domestic stuff and it always won.

 

[Tenntrapper]

Chamber reamer for a match chamber has something to do with it I'm sure. I've never encountered two factory consecutive serial # rifles where ones shoots great and the other terrible so I can't comment on that aspect. I do see the difference in CZ rifles that have a match barrel and those that do not tho firsthand. A tight match chamber appears to be a big factor.

Although I haven't seen it either...I've always heard that.
If it's the chamber, why doesn't everyone just use a match chamber reamer? Seems that would help everyone.

 

[dogsled]

I'm sure it would apply to centerfires as well, but for simplicity...let's keep it about rimfire rifles.
What makes one rifle more accurate than another...with everything else being equal?
Let's also just stick with bolt action for this...
Two rifles could come off the line one after the other, and could shoot different. I could understand a difference in say the first rifle...and the ten thousandth. Tooling wear, etc.
But even different manufacturers... generally speaking, why is CZ more accurate than say Marlin? Why are Annie's so accurate? What specifically is it about them that contributes to their accuracy? If it's the barrel, then why the (possible) difference in two consecutive rifles?
Just something I woke up curious about this morning. Any insight would be appreciated.
Thanks

I can't speak to rifles, but I can tell you my experiences with ammo. We used to have a group that got together to shoot rimfire in an ad hoc set up with metal targets at 25, 50, 75 and 100 yards. Everybody would toss in a quarter. Start at 25 yards and move to the next target after one shot, single miss elimination. I shot a Remington 581 that I bought from one of the other competitors, my buddy had a Remington too, 541T I believe.
We tried lots of different ammo to get the best accuracy from our rifles, Remington, Norma, PMC, CCI, Winchester, Federal, and anything else we could buy at the time.
My 581 loved the Winchester Wildcat ammo. Would shoot a ragged one hole group at 25 yards. The Federal and Remington would open up to 1.5" for me.
His 541T preferred the PMC Zapper and the CCI blazer with similar results for the Remington.

I have a Savage bolt action now that prefers the CCI and also performs poorly with Remington ammo.

 

[MUP]

Cost. Production cost would be the #1 reason for a company to not use a match dimension reamer for mass produced barrels. The reamers wear after so many uses and would have to be replaced often to keep match specs.

 

[Tenntrapper]

I can't speak to rifles, but I can tell you my experiences with ammo. We used to have a group that got together to shoot rimfire in an ad hoc set up with metal targets at 25, 50, 75 and 100 yards. Everybody would toss in a quarter. Start at 25 yards and move to the next target after one shot, single miss elimination. I shot a Remington 581 that I bought from one of the other competitors, my buddy had a Remington too, 541T I believe.
We tried lots of different ammo to get the best accuracy from our rifles, Remington, Norma, PMC, CCI, Winchester, Federal, and anything else we could buy at the time.
My 581 loved the Winchester Wildcat ammo. Would shoot a ragged one hole group at 25 yards. The Federal and Remington would open up to 1.5" for me.
His 541T preferred the PMC Zapper and the CCI blazer with similar results for the Remington.

I have a Savage bolt action now that prefers the CCI and also performs poorly with Remington ammo.

Do you think this comes down to barrel harmonics? I know some rifles shoot better with different ammo. Would that be chamber difference? Harmonics? Something else? A combination?

 

[Tenntrapper]

Cost. Production cost would be the #1 reason for a company to not use a match dimension reamer for mass produced barrels. The reamers wear after so many uses and would have to be replaced often to keep match specs.

I understand that...but all the reamers wear. Why not just make them to match specs? I can't imagine one spec is any more expensive to make than another.

 

[dogsled]

Do you think this comes down to barrel harmonics? I know some rifles shoot better with different ammo. Would that be chamber difference? Harmonics? Something else? A combination?

I would lean more towards harmonics and QC of the ammo than anything else.

 

[MUP]

Tolerances. Match tolerances. It's about the dimensions of the chamber being held to a very tight tolerance. Starting with a new reamer the tolerance is on the low end of the specified dimension, but as it wears it starts going to the high end. A match chamber just has a much tighter tolerance spec, and a reamer wears relatively quickly and goes out of that tight match tolerance within a certain number of uses, while a production chamber has less of a tolerance guideline to hold, and can be run longer, staying within the production spec longer.

 

[MUP]

And yes, regardless of match chamber or not, each rifle still has to be tuned to the particular ammo it prefers.

 

[MUP]

I believe it's Remington that will separate the first so many Model 700 barrels from new chamber and rifling reamers and designate them as their Sendero barrels.

 

[Iglow]

I can't speak to rifles, but I can tell you my experiences with ammo. We used to have a group that got together to shoot rimfire in an ad hoc set up with metal targets at 25, 50, 75 and 100 yards. Everybody would toss in a quarter. Start at 25 yards and move to the next target after one shot, single miss elimination. I shot a Remington 581 that I bought from one of the other competitors, my buddy had a Remington too, 541T I believe.
We tried lots of different ammo to get the best accuracy from our rifles, Remington, Norma, PMC, CCI, Winchester, Federal, and anything else we could buy at the time.
My 581 loved the Winchester Wildcat ammo. Would shoot a ragged one hole group at 25 yards. The Federal and Remington would open up to 1.5" for me.
His 541T preferred the PMC Zapper and the CCI blazer with similar results for the Remington.

I have a Savage bolt action now that prefers the CCI and also performs poorly with Remington ammo.

PMC was Aguila ammo, when they went under I had to scramble to find bricks of Aguila.

 

[Tenntrapper]

Tolerances. Match tolerances. It's about the dimensions of the chamber being held to a very tight tolerance. Starting with a new reamer the tolerance is on the low end of the specified dimension, but as it wears it starts going to the high end. A match chamber just has a much tighter tolerance spec, and a reamer wears relatively quickly and goes out of that tight match tolerance within a certain number of uses, while a production chamber has less of a tolerance guideline to hold, and can be run longer, staying within the production spec longer.

So basically...a "non match" chamber could possibly have a match chamber just by virtue of it being one of the first few tooled with a new reamer?

 

[TN Song Dog]

So basically...a "non match" chamber could possibly have a match chamber just by virtue of it being one of the first few tooled with a new reamer?

Adding for conversation factor, as im thinking you already have good thoughts on this subject.

First barrel from a new reamer would be closer to spec than the last, but wouldn't be match chamber. Tight match chambers can be finicky for the general public shooting cheap ammo and loading from a magazine into a chamber using a feed ramp. I'd say the user experience would go down if having issues with ftl and fte for most folks. Look at how a lot of Annie are single shot. Not having to strip off a mag and feed up into a chamber would keep bullet from deforming and reduce issues of misalignment going into a tight chamber.

I had a TacSol 10-22 variant with a tighter chamber than a standard ruger. It shot great, but it occasionally gave issues feeding reliably out of the ruger magazine design. I suspect too much issue coming up the feed ramp at a harder angle into the tighter chamber. It shot great, though. Wasn't a major problem, but was a frustration when shooting NRL and had to eject the round to keep going. Would leave you short a round or two on that stage, depending on what it took to clear the issue. Polishing the feed ramp may of helped, bit I just stuck with the bolt action instead of tinkering a ton with it.

 

[MUP]

So basically...a "non match" chamber could possibly have a match chamber just by virtue of it being one of the first few tooled with a new reamer?

It's possible I would think, at least as Tn Song Dog related, it would be the best dimensioned chamber for that particular reamer tho. I have a buddy that has trouble chambering and ejecting cheaper ammo in one of his custom match barrels, but he still keeps trying to find something cheaper to shoot.

 

[Tenntrapper]

Adding for conversation factor, as im thinking you already have good thoughts on this subject.

First barrel from a new reamer would be closer to spec than the last, but wouldn't be match chamber. Tight match chambers can be finicky for the general public shooting cheap ammo and loading from a magazine into a chamber using a feed ramp. I'd say the user experience would go down if having issues with ftl and fte for most folks. Look at how a lot of Annie are single shot. Not having to strip off a mag and feed up into a chamber would keep bullet from deforming and reduce issues of misalignment going into a tight chamber.

I had a TacSol 10-22 variant with a tighter chamber than a standard ruger. It shot great, but it occasionally gave issues feeding reliably out of the ruger magazine design. I suspect too much issue coming up the feed ramp at a harder angle into the tighter chamber. It shot great, though. Wasn't a major problem, but was a frustration when shooting NRL and had to eject the round to keep going. Would leave you short a round or two on that stage, depending on what it took to clear the issue. Polishing the feed ramp may of helped, bit I just stuck with the bolt action instead of tinkering a ton with it.

So, manufacturers give up some accuracy for reliability....for the average shooter? Makes sense I guess.

 

[Tenntrapper]

It's possible I would think, at least as Tn Song Dog related, it would be the best dimensioned chamber for that particular reamer tho. I have a buddy that has trouble chambering and ejecting cheaper ammo in one of his custom match barrels, but he still keeps trying to find something cheaper to shoot.

So using cheap ammo in a match chamber is a no-go. Guessing it's QC and specs of the cheaper ammo?

 

[MUP]

So, manufacturers give up some accuracy for reliability....for the average shooter? Makes sense I guess.

And to make sure that the average Joe has no issues chambering any factory ammo offering as well.

 

[MUP]

So using cheap ammo in a match chamber is a no-go. Guessing it's QC and specs of the cheaper ammo?

Maybe or maybe not, but the cheaper ammo, in some cases just will not chamber into a match chamber. It's a matter of the match chamber being the tighter, smaller dimension, while the factory ammo is apparently on the upper, larger side of the specification, like a press fit.