Inherently accurate calibers
- Thread starter Ben
- Start date
I don't know if this is relevant or not, but the Accurate Arms reloading manual has an interesting comment on the .357 SIG - they say that among all the calibers they have developed and tested loads for, the .357 SIG chronos remarkably consistent velocity (very low standard deviation) compared to other cartridges.
Hmm, I keep forgetting to tell my P99 in 40S&W that it's not supposed to be as accurate at 15 yards as my 9mms and 1911. But it just doesn't listen to me:
Sure, the recoil is much snappier than 9mm or 45acp, and it takes slightly longer for me to get back on target when shooting more rapidly, but the cartridge itself isn't inaccurate.
Note also that my P99 performs similarly well with the 357Sig conversion and I'm not trying to boost the self esteem of these two picked on calibers, I just assume that enough supports will chorus that 9mm and 45acp are always accurate as well.
Sure, the recoil is much snappier than 9mm or 45acp, and it takes slightly longer for me to get back on target when shooting more rapidly, but the cartridge itself isn't inaccurate.
Note also that my P99 performs similarly well with the 357Sig conversion and I'm not trying to boost the self esteem of these two picked on calibers, I just assume that enough supports will chorus that 9mm and 45acp are always accurate as well.
voyager4520
New member
It may not be the caliber's fault, but you're only talking about the diameter of the bullet. The casing, the design and grain of the bullet are huge factors that are only removed when you have multiple loads developed for one caliber.
Edit: Such as in the case of 38s, 380s, and 357s.
You could even argue that the 40SW isn't the greatest designed load for accuracy because it's identical caliber brother, the 10mm, always produces tight groups.
Edit: Such as in the case of 38s, 380s, and 357s.
You could even argue that the 40SW isn't the greatest designed load for accuracy because it's identical caliber brother, the 10mm, always produces tight groups.
Ben, a kindred spirit!
I'm a bit of a physics buff myself; however, more toward particle physics and cosmology. I earn my daily bread as a lawman, too.
Among bench rest shooters, the current theme is a short, wide cartridge burns powder in a more uniform and reproducible manner, and is therefore more inherently accurate than a narrow, long cased round. This gives pride of place to the .223 and 6mm PPC (can't remember the names involved) rounds in bench rest shooting.
There may be a similar effect in handgun cases. The bottle neck of the .357 SIG may keep powder in the case during burn time and therefore give more consistent burn rates. But then, why isn't the .30 Luger or .30 Mauser desired as 'accurate' rounds?
The .38 and .44 Specials have been hailed as 'accurate' rounds for years. Out of revolvers, no less. They're not bottle necked, so who knows? I think it may have something to do with bullet design and bearing surface in the bore. Elmer Keith claimed his bullet designs centered themselves in the chamber throat and forcing cone and that made them accurate.
Super .38 has been mentioned, regarding headspace on the rim. I've got a Super built as a target gun and it is simply dandy. However, I use bullets with as much bearing surface as I can.
.32 ACP has never been considered greatly accurate. The standard bullets are short and seem to have a short area of contact with the rifling. To my knowledge, no one has ever built a serious 'match gun' chambered in .32 ACP. Again, who knows? For that matter, who has the money to have one built just to find out?
The .45 ACP is used in competition simply because it was the U. S. sidearm for so long. It was required in Bullseye shooting and popularized by the late Jeff Cooper in 'combat' shooting. As a result, the guns for .45 ACP have been highly developed and refined for accuracy. Not to mention years of ammunition research. It is still popular in part due to the large diameter; a shot hole touching the scoring ring gets the higher value.
The 9x19 is now the official round of the U. S. Armed Forces and is undergoing the same research and refinement as the 1911 did in the old days. Ammunition is also being researched and experimented and developed and such.
I'm think, but am not so sure some cartridge is 'inherently' more accurate than another in a scientific test sense. (I think cartridge internal shape has an effect in the matter.) Most accuracy winners are a combination of the round and the weapon involved. Face it, a S&W "N" frame revolver is going to shoot better than a Glisenti pistol any day of the week. To determine definitely the answer, one would have to conduct an experiment with controlled equipment and conditions. 44AMP mentioned using the Contender pistol as the test frame and I think that would be a perfect place to start. Sadly, I don't have one and probably can't afford one in the near future. Nor does Thompson-Center manufacture all those various barrels that used to be available.
I'd happily do the research if I could get the funding.
I'm a bit of a physics buff myself; however, more toward particle physics and cosmology. I earn my daily bread as a lawman, too.
Among bench rest shooters, the current theme is a short, wide cartridge burns powder in a more uniform and reproducible manner, and is therefore more inherently accurate than a narrow, long cased round. This gives pride of place to the .223 and 6mm PPC (can't remember the names involved) rounds in bench rest shooting.
There may be a similar effect in handgun cases. The bottle neck of the .357 SIG may keep powder in the case during burn time and therefore give more consistent burn rates. But then, why isn't the .30 Luger or .30 Mauser desired as 'accurate' rounds?
The .38 and .44 Specials have been hailed as 'accurate' rounds for years. Out of revolvers, no less. They're not bottle necked, so who knows? I think it may have something to do with bullet design and bearing surface in the bore. Elmer Keith claimed his bullet designs centered themselves in the chamber throat and forcing cone and that made them accurate.
Super .38 has been mentioned, regarding headspace on the rim. I've got a Super built as a target gun and it is simply dandy. However, I use bullets with as much bearing surface as I can.
.32 ACP has never been considered greatly accurate. The standard bullets are short and seem to have a short area of contact with the rifling. To my knowledge, no one has ever built a serious 'match gun' chambered in .32 ACP. Again, who knows? For that matter, who has the money to have one built just to find out?
The .45 ACP is used in competition simply because it was the U. S. sidearm for so long. It was required in Bullseye shooting and popularized by the late Jeff Cooper in 'combat' shooting. As a result, the guns for .45 ACP have been highly developed and refined for accuracy. Not to mention years of ammunition research. It is still popular in part due to the large diameter; a shot hole touching the scoring ring gets the higher value.
The 9x19 is now the official round of the U. S. Armed Forces and is undergoing the same research and refinement as the 1911 did in the old days. Ammunition is also being researched and experimented and developed and such.
I'm think, but am not so sure some cartridge is 'inherently' more accurate than another in a scientific test sense. (I think cartridge internal shape has an effect in the matter.) Most accuracy winners are a combination of the round and the weapon involved. Face it, a S&W "N" frame revolver is going to shoot better than a Glisenti pistol any day of the week. To determine definitely the answer, one would have to conduct an experiment with controlled equipment and conditions. 44AMP mentioned using the Contender pistol as the test frame and I think that would be a perfect place to start. Sadly, I don't have one and probably can't afford one in the near future. Nor does Thompson-Center manufacture all those various barrels that used to be available.
I'd happily do the research if I could get the funding.
David the Gnome
New member
Olympic level target shooting is done with small bore 22LR and air rifles. It makes sense that the ultra-low recoil of the 22LR would naturally lend itself to greater accuracy. So for an inherently accurate caliber, I would say 22LR is a pretty good choice. 
Oh, my brain hurts
There are so many variables in shooting that it is meaningless to try to isolate one of them as the cause for relative accuracy or inaccuracy. Think about it: there's the type of gun (revolver vs, semi-auto) the operation of the gun's trigger (single vs. double action in revolvers, sa vs. da vs. striker fired in semis), the particular make and model of the gun (for example, is a Smith revolver a more accurate shooter than, say, a Charter Arms?), how the particular gun was built (did the person who did the final assembly have a hangover on the day he/she put your gun together?), the caliber of the bullet, the type of bullet, the powder charge, the type of powder (fast vs. slow burning), whether the bore of the gun is clean or dirty when the bullet passed through it, the skill of the shooter, the shooter's relative efficacy on the day he/she fires the bullet, wind, temperature, humidity, altitude, distance from the target, and a host of other factors that I can't catalogue. Given all of these variables, this discussion, while interesting, is essentially pointless.
When I was a mere lad I deluded myself into believing that I could become a good racehorse handicapper. I spent a lot of time and a lot of money at the racetrack proving beyond doubt that the task I'd set for myself was hopeless. What I discovered there was that there were too many variables to handicap. What's true about horse racing is equally true about shooting. There are too many variables to generalize about a particular caliber's accuracy. One can say that a particular caliber in a particular gun under certain conditions will produce average groups at a predetermined yardage of "x" width. That's about it.
There are so many variables in shooting that it is meaningless to try to isolate one of them as the cause for relative accuracy or inaccuracy. Think about it: there's the type of gun (revolver vs, semi-auto) the operation of the gun's trigger (single vs. double action in revolvers, sa vs. da vs. striker fired in semis), the particular make and model of the gun (for example, is a Smith revolver a more accurate shooter than, say, a Charter Arms?), how the particular gun was built (did the person who did the final assembly have a hangover on the day he/she put your gun together?), the caliber of the bullet, the type of bullet, the powder charge, the type of powder (fast vs. slow burning), whether the bore of the gun is clean or dirty when the bullet passed through it, the skill of the shooter, the shooter's relative efficacy on the day he/she fires the bullet, wind, temperature, humidity, altitude, distance from the target, and a host of other factors that I can't catalogue. Given all of these variables, this discussion, while interesting, is essentially pointless.When I was a mere lad I deluded myself into believing that I could become a good racehorse handicapper. I spent a lot of time and a lot of money at the racetrack proving beyond doubt that the task I'd set for myself was hopeless. What I discovered there was that there were too many variables to handicap. What's true about horse racing is equally true about shooting. There are too many variables to generalize about a particular caliber's accuracy. One can say that a particular caliber in a particular gun under certain conditions will produce average groups at a predetermined yardage of "x" width. That's about it.
This is what I was thinking for example; I'm thinking that the 40 was designed as a COMBAT round, so the guns that chamber it are typically combat guns that deliver combat accuracy. So the round hasn't had a sufficient platform to deliver the round more accurately.
Basically, they design guns around the intent of the cartridge.
Ben
Basically, they design guns around the intent of the cartridge.
Ben
45_Shooter
New member
I can tell you that at least one article I've read recommends staying away from the .40 S&W when pinpoint accuracy is desired; it has to do with it's inherent pressure sensitivity to relatively small changes.
9mm has a more sharply tapered case and theoretically should allow a tighter chamber to be utilized, and given that it's not incredibly sensitive like the .40, and heavy subsonic loads can be used, I might say the 9mm has the most accuracy potential.
The .45 is probably the most accomodating to small changes in OAL, charge, etc. because of its large case and every load is inherently subsonic in nature. However, it's real advantage is the 100 years of development it's had. I'd say the .45 is the easiest to make accurate of the autoloading cartridges.
For wheelguns, the .38 special had the most development and probably is able to pull the tightest groups when using the old 148 grain HBWC puffballs. Other than a whole lot of development though there isn't much else that makes it inherently more accurate than any other wheelie cartridge.
9mm has a more sharply tapered case and theoretically should allow a tighter chamber to be utilized, and given that it's not incredibly sensitive like the .40, and heavy subsonic loads can be used, I might say the 9mm has the most accuracy potential.
The .45 is probably the most accomodating to small changes in OAL, charge, etc. because of its large case and every load is inherently subsonic in nature. However, it's real advantage is the 100 years of development it's had. I'd say the .45 is the easiest to make accurate of the autoloading cartridges.
For wheelguns, the .38 special had the most development and probably is able to pull the tightest groups when using the old 148 grain HBWC puffballs. Other than a whole lot of development though there isn't much else that makes it inherently more accurate than any other wheelie cartridge.
.22
But....a lot of this discussion has centered on cartridges. That's all well and good but....the OP was about calibers, not at all the same thing.
Are .22 caliber bullets inherently more accurate than .355(6), .357(8), .400, .429, .452 bullets?
Pete
Arguably, the .22 is the most accurate cartridge. I don't believe that recoil has anything to do with it - or at least not much. More to the point is that the best .22LR match ammo tends to be subsonic and avoids the transition problems that other cartridges have when the bullet slows. Then, again, many pistol loadings are subsonic.
But....a lot of this discussion has centered on cartridges. That's all well and good but....the OP was about calibers, not at all the same thing.
Are .22 caliber bullets inherently more accurate than .355(6), .357(8), .400, .429, .452 bullets?
Pete
Chuckusaret
Moderator
Can't tell the difference between my 9MM and two 40 calibers. Both are darn accurate but all three have been cleaned up by a "Real" gunsmith.
Ben, I see a teeny flaw in your logic.
The .45 Awfulmatic was designed as a combat weapon. The M1911 pistol and the M1911A1 and the Colt Government Model were all designed as a personal defense - badguy repellent.
So if the .40S&W is not so accurate because it was designed for combat, how'd the .45 get that way?
Sir, I respectfully submit you are discussing the pistols and not the cartridge.
45 Shooter, the 9x19 NATO, or 9mm Parabellum, aka 9mm Luger operates at a chamber pressure of 34,000 psi maximum; whereas the .40 S&W runs a maximum of 32,600 psi. The .40 S&W has a larger case capacity than the 9x19. In plain words, the .40 S&W is not as sensitive to small variations of powder charge as the small and higher pressure 9x19. That's just how interior ballistics work. I'm not going to argue with the article you read, but it simply isn't so. (HIgh pressure and small burn chambers are what are sensitive to changes in powder charge.)
Aside from that, one of the reasons the .45 ACP, the .38 Special and so on are so accurate as target guns is they are not loaded to maximum pressures in target loads. Therefore, 'target' loads for .40 S&W need not run at maximum either.
But you're right about all the research and development in .45 ACP, .38 Spl, .44 Spl and Magnum and so forth. Maybe in another thirty years, the .40 S&W will be the nee plus ultra target pistols.
Dark Gael, your question about bullets is a good one. I know bench rest shooters agree 6mm is the largest bullet diameter that can be 'perfectly' balanced and symmetrical internally. That's why the ultra bench rest shooters don't shoot .308 caliber rifles. In handguns, I think it's more the .22 rimfire bullet is typically rather soft and fits itself to the bore better than larger, centerfire bullets. On the other hand, I shoot my .45 wadcutter gun better than I shoot my 41 Smith .22 pistol. That's dopey, I know, but it's true.
The .45 Awfulmatic was designed as a combat weapon. The M1911 pistol and the M1911A1 and the Colt Government Model were all designed as a personal defense - badguy repellent.
So if the .40S&W is not so accurate because it was designed for combat, how'd the .45 get that way?
Sir, I respectfully submit you are discussing the pistols and not the cartridge.
45 Shooter, the 9x19 NATO, or 9mm Parabellum, aka 9mm Luger operates at a chamber pressure of 34,000 psi maximum; whereas the .40 S&W runs a maximum of 32,600 psi. The .40 S&W has a larger case capacity than the 9x19. In plain words, the .40 S&W is not as sensitive to small variations of powder charge as the small and higher pressure 9x19. That's just how interior ballistics work. I'm not going to argue with the article you read, but it simply isn't so. (HIgh pressure and small burn chambers are what are sensitive to changes in powder charge.)
Aside from that, one of the reasons the .45 ACP, the .38 Special and so on are so accurate as target guns is they are not loaded to maximum pressures in target loads. Therefore, 'target' loads for .40 S&W need not run at maximum either.
But you're right about all the research and development in .45 ACP, .38 Spl, .44 Spl and Magnum and so forth. Maybe in another thirty years, the .40 S&W will be the nee plus ultra target pistols.
Dark Gael, your question about bullets is a good one. I know bench rest shooters agree 6mm is the largest bullet diameter that can be 'perfectly' balanced and symmetrical internally. That's why the ultra bench rest shooters don't shoot .308 caliber rifles. In handguns, I think it's more the .22 rimfire bullet is typically rather soft and fits itself to the bore better than larger, centerfire bullets. On the other hand, I shoot my .45 wadcutter gun better than I shoot my 41 Smith .22 pistol. That's dopey, I know, but it's true.
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best
Archie:
I've read that info about the 6mm and the benchrest guys.
Is there a handgun equivalent to the 6mm?
Pete
Archie:
I know what you mean. I've shot my best highest scores with my .45 (though my best precision scores are with the .22). That's not, I believe, because the bullets are more accurate; it has more to do with me and the gun/body system (and big bullets).
I've read that info about the 6mm and the benchrest guys.
Is there a handgun equivalent to the 6mm?
Pete
Bigger caliber = bigger hole.
I don't formally compete, so I'm not clear on scoring details, but in my case, it's simply because my .38spl HBSW makes a bigger and cleaner hole that touches a ring a similarly placed .22LR hole doesn't. Group size, though, when measured c-c is similar.
45_Shooter
New member
It was Hodgdon's reloading annual 2009 issue; I believe it's still on the shelves if anyone want's to read it.
From what I've read in other sources (I'm not an expert in this area and I won't pretend to be one), the .40 S&W becomes very sensitive when heavier weight bullets are used due to the reduction in case capacity. From what I understand, this (namely bullet setback from repeated chambering) is one of the primary reasons for the frequency of kabooms reported in handguns chambered in this caliber.
Since most accuracy-based target shooting is done with heavy bullets for caliber, this probably represents Hodgdon's reasoning behind the recommendation to stay with 9mm and .45 for accuracy.
45 Shooter
Hodgdon (despite the irrational spelling) is a respected source of gunpowder and information. Notwithstanding, the statement still doesn't make sense from an internal ballistics standpoint. I'm going to have to find a 2009 Hodgdon's manual and check this out. It really sounds odd.
"...heavier weight bullets ... [reducing] case capacity..." and "...bullet setback from repeating chambering..." are two completely different factors. Also, since the original bullet weight in the .40 was 180, I find it curious to list 'heavier' bullets as an overpressure factor in this context.
"... frequency of kabooms..." How frequent is frequent? I've had a H&K USP40 for seven to ten years now, and it's never blown up with my handloads. Nor do I know of any first hand information regarding blowups of .40 S&W pistols - other than Glocks. They've all been in Glocks as far as I've heard. Maybe it's a Glock design problem in their 40s rather than a cartridge problem?
And, as I mentioned, target loads in handguns are pretty always loaded to lower pressure levels than 'standard' or 'service' loads. No reason to do otherwise with .40 S&W, is there?
Please note, 45 Shooter, I'm not arguing with you reporting what you read; I'm finding the original information illogical.
Ben, that was my point.
Dark Gael, any handgun rounds on the same principle as the PPC rounds? Let's see, short and wide... short and wide... .45 ACP comes to mind. .44 Special (and the obsolete .44 Russian) more or less fit in the category. For that matter, on a ratio perspective, .40 S&W is shorter and wider than 9x19. I think the .45 GAP is shorter and just as wide as .45 ACP; so it could have prospects as a target round. But I doubt if there will be a mass migration of target shooters to buy new barrels on that basis.
Mr Borland, you are of course correct on the subject of 'bigger holes get more scoring rings'. I mentioned that in my first posting, responding to Ben. Some of us need all the help we can get. If I could get away with it, I'd shoot a ".50 Very Reduced" to get a little more edge.
Hodgdon (despite the irrational spelling) is a respected source of gunpowder and information. Notwithstanding, the statement still doesn't make sense from an internal ballistics standpoint. I'm going to have to find a 2009 Hodgdon's manual and check this out. It really sounds odd.
"...heavier weight bullets ... [reducing] case capacity..." and "...bullet setback from repeating chambering..." are two completely different factors. Also, since the original bullet weight in the .40 was 180, I find it curious to list 'heavier' bullets as an overpressure factor in this context.
"... frequency of kabooms..." How frequent is frequent? I've had a H&K USP40 for seven to ten years now, and it's never blown up with my handloads. Nor do I know of any first hand information regarding blowups of .40 S&W pistols - other than Glocks. They've all been in Glocks as far as I've heard. Maybe it's a Glock design problem in their 40s rather than a cartridge problem?
Which is why the .45 ACP in target form ususally runs 180 to 200 grain bullets? Standard loads use a 230 grain bullet. .38 Special target loads are 148 grain wadcutters, as opposed to the standard 158 grain bullet. The only 9x19 target loads are service equivalent loads, they run the same bullet weight as issue ammo.
And, as I mentioned, target loads in handguns are pretty always loaded to lower pressure levels than 'standard' or 'service' loads. No reason to do otherwise with .40 S&W, is there?
Please note, 45 Shooter, I'm not arguing with you reporting what you read; I'm finding the original information illogical.
Ben, that was my point.
Dark Gael, any handgun rounds on the same principle as the PPC rounds? Let's see, short and wide... short and wide... .45 ACP comes to mind. .44 Special (and the obsolete .44 Russian) more or less fit in the category. For that matter, on a ratio perspective, .40 S&W is shorter and wider than 9x19. I think the .45 GAP is shorter and just as wide as .45 ACP; so it could have prospects as a target round. But I doubt if there will be a mass migration of target shooters to buy new barrels on that basis.
Mr Borland, you are of course correct on the subject of 'bigger holes get more scoring rings'. I mentioned that in my first posting, responding to Ben. Some of us need all the help we can get. If I could get away with it, I'd shoot a ".50 Very Reduced" to get a little more edge.