Advantages / disadvantages of the "open slide"-design

[Walt Sherrill]

Originally Posted by Limnophile

I read somewhere that the Beretta open slide design was intended to increase ejection reliability.

I think I mentioned this earlier. I don't see HOW an open slide can have any role in ejection-related reliability.

When slide moves back the extractor draws the spent round out of the chamber.

• If the round isn't pulled cleanly out of the chamber by the extractor it's either still in the chamber or left loose in the chamber area, laying on top of the magazine.
  
• If it's still in the chamber, the open slide isn't going to do a thing. If it's laying loose in the chamber area on top of the mag, the slide will be moving so fast, trying to feed the next round, all you're going to have is a jam...

Maybe something else is going on that I don't understand... but otherwise, I don't see how that open slide can do much to improve ejection reliability...

[Gats Italian]

The open top slide aids in ejection by sporting the biggest ejection port for 9mm cases you will ever see.

On closed top autos, the size and shape of the ejection port is critical to flawless ejection. With a CZ-75 for example, I have seen weakly ejected cases, (from sticking momentarily in the chamber, or an underpowered round providing an insufficient recoil impulse, etc.), fail to clear the smallish ejection window cleanly, bounce back, and jam the pistol.

Never seen that particular jam on a beretta 92 unless a nearby obstacle to the flying brass was the culprit.

[Limnophile]

Walt,

Here is a quote from an October 2011 story about the role of the M9's open-top slide in the pistol's reliability:

The M9 has been accused of being less reliable and less durable than other pistols in its class. This is simply not true. The open-top slide, while it may allow a lot of superficial dust and sand to “stick” to the weapon, is one of the features that makes it so reliable. It is much more difficult to “bind up” than other pistol designs. The M9’s slide is “self-regulating” meaning during the firing cycle, some rather violent forces act to expel any trapped foreign debris in the action.
-http://www.guns.com/review/2011/10/28/coming-out-in-defense-of-the-beretta-m9/

Nothing specific, unfortunately. I don't recall hearing complaints about the M9, other than typical 9-vs-.45 stuff, until it went to war in desert environs. In every article I've read about the promised Army Modular Handgun competition, the open-top slide is vilified.

[tipoc]

I don't recall hearing complaints about the M9, other than typical 9-vs-.45 stuff, until it went to war in desert environs. In every article I've read about the promised Army Modular Handgun competition, the open-top slide is vilified.

Let's see. The 92 entered U.S. military service in 1986 or so. Went to teh invasion of Panama. The first Gulf war began in 1990. The M9 went there. Went to Somalia in 1992 as well. Then back to the Second Gulf war. In all of that the biggest complaint was the bad magazines that were bought aftermarket by the Army.

So in 25 years the U.S. military has used the M9 in the dust and dirt of north Africa and the mid-east. The result of that is they ordered many more M9s. They have not had an official complaint about the gun in sand.

The complaints about the open slide design have appeared in some articles discussing the possibility of a new handgun for the U.S. military. But they have not come from officially the U.S. military.

Given that the 92 and it's open slide predecessors (the Helwan for example) have served in the mideast in just about every nation there (Israel to Tunisia) I'm willing to say the open slide ain't a big disadvantage in the sand.

You can scroll down here and see a few of the dusty places that it is the service sidearm...

http://en.wikipedia.org/wiki/Beretta_92

The open top slide aids in ejection by sporting the biggest ejection port for 9mm cases you will ever see.

That's about right.

tipoc

[Walt Sherrill]

Originally Posted by Gats Italian

The open top slide aids in ejection by sporting the biggest ejection port for 9mm cases you will ever see.

If the round hasn't been caught by the extractor, it's not being going to be extracted or ejected. The open slide doesn't help there.

If it has been caught by the extractor, it will have moved back with the opening slide, and the open area on the top of the slide is functionally meaningless (with regard to extraction or ejection.) The open slide doesn't help there.

If the spent case is partially extracted (the extractor loses its grip), you're still going to have a collision with the next round being pushed out of the magazine and fed to the chamber; you'll have something like a "stovepipe" jam and all of that will be happening near the breech area, as the slide closes -- and not near the open part of the slide. The slide will be moving far too quickly for the shooter to flip an un-ejected casing away... The open slide doesn't help much there, either.

I may be wrong --but I would argue that guns, when they cycle, don't work in a way that the Beretta's open slide can have much role in ejection-related issues.

Originally Posted by Limnophile

Here is a quote from an October 2011 story about the role of the M9's open-top slide in the pistol's reliability:

Could be that it plays some role in overall reliability. But I'm not sure that "binding up" has anything to do with ejection reliability.

Just the fact that junk might not accumulate inside the slide in bad conditions might be helpful. That said, there's still room under the barrel for junk to accumulate, and it's just as easy for the junk to get in there with the slides moves to the rear as with other guns -- and easier, when the slide is forward. I've never heard of problems with the open slide.

The only complaints I've heard about from guys who have used them in combat had to do with magazines -- and some of those weren't factory-issued mags, but later, government-issued replacement mags.

[tipoc]

Here is a slo-motion vid of the 92 extracting and ejecting. We can observe.

https://www.youtube.com/watch?v=9eT2OststG0

If the round hasn't been caught by the extractor, it's not being going to be extracted or ejected. The open slide doesn't help there.

If the case has not been caught by the extractor on any gun that has one it won't help ejection on any gun. So for purposes of this discussion I don't think that point is a useful one.

I think that if we look at the video (there are others like it) we note that the top of the slide is open where the round is ejected. We also see that the great bulk of the open area of the slide forward of that point plays no role in ejection as the slide does not retract that far for it to play any role.

The trend over the years has been towards larger ports. the original port on the 1911 has been enlarged and those on the Glock, Sig and M&P line, etc. as enormous by comparison to older designs. This helps to increase reliability of the gun by aiding in clean ejection.

The wide open area of the M92s slide makes for a very large ejection port in that area that it matters to clean ejection.

I think that the open slide design plays little role beyond that area one way or the other.

tipoc

[Gats Italian]

Of course you didn't bother to tangle with the issue I identified.

Ammo can be inconsistently loaded. One way this manifests itself is how positively the recoil impulse manages to impart rearward momentum to the slide.

In the case of an underpowered round, it can still facilitate proper function and not see the case energetically tossed clear of the ejection port.

The ejected case from a Beretta 92 doesn't have to have the precise ejection timing for a case to clear a little window cut into the slide. It can weakly eject at nearly any angle and the spent case will clear the chamber area.

[Walt Sherrill]

Originally Posted by Gats Italian

Of course you didn't bother to tangle with the issue I identified.

Ammo can be inconsistently loaded. One way this manifests itself is how positively the recoil impulse manages to impart rearward momentum to the slide.

In the case of an underpowered round, it can still facilitate proper function and not see the case energetically tossed clear of the ejection port.

The ejected case from a Beretta 92 doesn't have to have the precise ejection timing for a case to clear a little window cut into the slide. It can weakly eject at nearly any angle and the spent case will clear the chamber area.

I underlined the key part of your comment, above.

If the ammo is weak but still allows proper function, even if the slide is moving a bit more slowly, the round is still being held by the extractor against the breech face until it hits the ejector. The speed of the slide isn't going to change much about what is purely a mechanical process -- It's not a TIMING issue.

If the round hits the ejector everything is lined up properly for ejection and ejection will likely happen -- just not as robustly or predictably as when the slide is moving with a higher speed. I would argue that the larger ejection port adds little or nothing to ejection process.

If the slide is moving so slowly that the ejected round doesn't clear the chamber area, it's also possible that the slide won't have enough force to strip the next round and feed it into the chamber -- and then you've either got to clear a jam or manually push the slide closed.

.

[DAVID NANCARROW]

I fail to see how an open topped slide is going to help a weakly loaded fired case eject. If the round has sufficient power to extract the empty case and strike the ejector, it still clears the ejection port at the same angle-just not with the force that one would expect in a higher pressure loading. The ejection is assisted by the next round in the magazine pushing up-that part of it would be a timing issue, controlled by the magazine feed lips.

I have loaded powder puff loads for my lady when she was just beginning to learn how to handle a pistol. These loads were exceptionally weak with the empty brass falling about 2 feet to her right side. In no way did the angle of ejection change, just the distance the empty brass flew. BTW, these loads were run in a Gold Cup Trophy Match 45 ACP, a closed slide. IIRC, the load was 4 grains of Accurate #2 behind a 200 grain LSWC and OAL at 1.250". All I expected her to do with the load was to feel the trigger and get used to the slide cycling. We ran a few hundred rounds of that setup and everything functioned well.

I am not down on open topped slides vs closed, but I really do not see much if any advantage.

[btmj]

The evolution of pistols has lead to larger and more streamlined ejection ports. Compare a WWII 1911A1 to a modern 1911. Compare a SW 59 to a SW M&P. Compare any pistol designed before 1970 to any modern pistol, and the large profiled ejection port is one of the most obvious differences. A small ejection port requires everything to go just right, while a large streamlined port allows some "slop" in the way the gun cycles and the cartridge ejects. It is nonsensical to argue that an enlarged, profiled ejection port is not a significant factor in the pistols reliability. If it weren't, why would sig, glock, walther, HK, SW, ruger, springfield, colt, CZ, Taurus, keltec, Wilson, kimber, etc all go the trouble of making an enlarged streamlined ejection port.

The 92 open slide is simply a very very large ejection port.

[Walt Sherrill]

Originally Posted by btmj

... It is nonsensical to argue that an enlarged, profiled ejection port is not a significant factor in the pistols reliability. If it weren't, why would sig, glock, walther, HK, SW, ruger, springfield, colt, CZ, Taurus, keltec, Wilson, kimber, etc all go the trouble of making an enlarged streamlined ejection port.

Couldn't we use that SAME LOGIC to say that plastic grips or polymer frames are significant factors in pistol reliability? I would argue, however, that just because it seems intuitively obvious that the Beretta's open slide (your "larger ejection port") would aid ejection, thinking so doesn't make it so.

Can you offer us some evidence that a profoundly larger ejection port (like that found in the Beretta) has made THAT weapon more reliable than all of the other guns you've mentioned?

All of the guns you've cited above are generally considered very reliable weapons, but NONE of them has a VERY LARGE (Beretta-like) ejection port. it would seem logical, given your assertion above, to assume that the Beretta would almost have to be SIGNIFICANTLY more reliable than the other guns if ejection port size is really all THAT important a factor in ejection reliability. IS IT?

With a locked breech gun, when a round is fired, the slide and barrel move to the rear, and then start to separate. The empty cartridge is held in the chamber and against the breech face until pressure drops. With some guns an extractor isn't even used. With all of the other guns you mentioned as the slide moves back, the smaller (than Beretta) ejection port moves, too! That port is always where it needs to be and if the designers have made it big enough in the first place, and the round works as it should -- it really doesn't need to be much bigger! If the pressure from the fired round is sufficient to hold the round in place, that spent casing is going to go the rear and it's going to hit the ejector and flip out, somewhere.

If something happens during the firing cycle, like a grossly underpowered round or a ruptured case, and the round doesn't make it to the ejector, it's going to stay in the in the chamber/feed ramp/mag area, as there's not really anywhere else for it to go: the explosion of the round started the casing moving to the rear (along with the slide and barrel) and there's not much way for it to go in any other direction! It's unlikely to flip forward, which would be necessary for that open slide to be a factor. The magazine and the next round (ready to be stripped) are going to keep it the spent casing from going down very far.

If the fired round is underpowered or has ruptured, the slide isn't going to cycle properly anyway, and things are going to quickly come to a stop: there'll probably be a jam as the next round (if the slide can strip it) tries to enter the same relatively small space.

I would argue that main reason the VERY LARGE Beretta ejection port isn't going to be play too big a role in ejection reliability is that the round really won't leave the rear of chamber and breech area unless it gets kicked out by the ejector.

.

[DAVID NANCARROW]

If it weren't, why would sig, glock, walther, HK, SW, ruger, springfield, colt, CZ, Taurus, keltec, Wilson, kimber, etc all go the trouble of making an enlarged streamlined ejection port.

Look up the Petter improvement to the Browning patent for recoil operated pistols.

The reason pistols such as SIG and Glock have the oversized ejection port is the Petter improvement did away with the internal slide lugs of the 1911 and used instead a squared off barrel at the chamber to fit the ejection port. This accomplishes the same thing as the original internal slide and barrel lugs. This is really more of an ease in manufacturing than anything else, and has not one single thing to do with more positive or reliable ejection.

The US military used the small ejection port 1911/A1's for a few years if I recall correctly, and without issue even when they were shot to very loose fit. In fact, about 70+ years without an ejection problem inherent in the design. So long as the relevant parts are within military spec, it keeps doing what it was designed to do.

If anything, and this is only theoretical, the "very large ejection port" on the Beretta compromises the strength of the slide, although it doesn't seem to cause any day to day reliability problems. The top of the slide in a dropping block action doesn't lock the barrel at the top as a swinging link does, so there is no real need for metal to be there. The original design, the Walther P-38 also has an open top design.

I am still trying to understand how an open top slide is going to affect ejection in any meaningful way? The ejector, at least in my Beretta is fixed, and is not capable of adjusting its location. It depends entirely upon the slide retracting far enough for the empty case, held by the extractor, to strike the ejector with enough force to send it on its way.

I have no doubt that if someone made a closed top slide with an adequate opening for ejecting brass for a Beretta that the pistol would function. The only change might be to install a lighter recoil spring to compensate for the heavier slide.

I think its interesting that most of the recoil operated pistols use the Browning design or the Petter Improvement to the Browning well after the patents on all of them expired a very long time ago. Having that choice, most manufacturers stay away from the dropping block.
Manufacturing ease? That would be my guess.

[44 AMP]

Couldn't we use that SAME LOGIC to say that plastic grips or polymer frames are significant factors in pistol reliability? I would argue, however, that just because it seems intuitively obvious that the Beretta's open slide (your "larger ejection port") would aid ejection, thinking so doesn't make it so.

I suppose you could use the "same logic" to argue anything, but that doesn't mean you would be correct.

I think plastic grips or polymer frames are more like radial tires. They may give you a better "grip" on the road, they may give you better gas mileage, but they have NOTHING to do with how the car engine runs...

I think the belief that an open slide is an advantage to positive ejection simply comes from the general attitude that, if something is good, then more of it must be better.

And, while true for some things, it is not true for everything, and even when it is true, it is often not a matter of a direct arithmetic progression. It can also be a direct progression, but only apply over part of the possible range of outcomes, as well.

thinking it is a constant linear relationship leads you into the trap of extremes.
All auto pistols require some clearance (distance) between the slide and the frame, in order to function, right? And if more is better (an assumption) then the most reliable pistol possible would have the slide miles away from the frame!

IT is possible that the open slide design might have some slight statistical (mathematically definable) advantage, but if it does, it is either not easily quantified,, or is so small as to have no practical effect.

Once you have enough, having more doesn't necessarily get you improved results.

[Walt Sherrill]

Originally Posted by 44 AMP

I suppose you could use the "same logic" to argue anything, but that doesn't mean you would be correct.

I think plastic grips or polymer frames are more like radial tires. They may give you a better "grip" on the road, they may give you better gas mileage, but they have NOTHING to do with how the car engine runs...

That wasn't a serious argument -- just an example of making a claim without any supporting evidence.

From a different perspective, the "plastic grip/polymer frame" claim was also a version of the kind of argument that gives the statistician's or scientist's headaches. They will immediately point out that CORRELATION DOES NOT IMPLY CAUSATION.

Just because a trait or mechanism is present when something happens doesn't AUTOMATICALLY mean that the trait or mechanism caused that "something" to happen. Thus far we have only claims of improved ejection performance but no evidence that the claims are based on fact. (They may be based in fact, but the those facts are not being seen or shared.) Even if we see enhanced ejection reliability in the open-topped Beretta slides, we don't know for sure that it's due to the open-top slide, or something else, like a better extractor design -- until those other variables are also examined.

Beretta claims on its website that "the open-slide design practically eliminates 'stove-piping' and helps flawless cycling and feeding even after thousands and thousands of rounds." In my experience, if the extractor loses it's grip on that spent round, the casing is still moving to the rear and hasn't really moved away from the standard ejection port area of the slide. If there's enough speed and pressure, the round might still eject. If it's not moving fast enough or not positioned properly it could go astray.

If that happens, the slide is already started to change directions as it strips the next round from the mag and moves it forward. That is where and when the stovepipe problem generally occurs -- at the chamber end of the barrel, when spent case and live round collide, as the slide (and then the barrel) move forward. It seems to me that at that point, the open slide can play almost no role in preventing stove-pipe jams. (That said, I'll be the first to admit there may be something I'm overlooking, but it's not because I haven't tried to see it. I acknowledge that I'm still a student on this general topic, so I welcome correction/education if I've misunderstood or misrepresented what's happening.) It could be that their approach has eliminated "stovepipe" jams but just given us a different kind of jam... not explained.

I've owned several Berettas (92s including a Vertec, and a 96), and I don't remember having stovepipe problems with any of them -- probably because they were all NEW and unlikely to have damaged or weakened extractors or other problems caused by wear. But the same is true of every NEW gun I've purchased -- including SIGs, Glocks, Steyrs, CZs, S&Ws, different 1911s, and even five different Kel-Tec guns!!

.

[Limnophile]

Walt,

You could ask Beretta USA directly: http://berettausa.custhelp.com/app/u...t/redirect/ask.

Let us know what they say.

[Walt Sherrill]

Originally Posted by limnophile

Walt,

You could ask Beretta USA directly: http://berettausa.custhelp.com/app/u...t/redirect/ask.

Let us know what they say.

Heck, you went to the trouble of finding that link, why didn't YOU ask them and share their response, here?

To me, that would be like asking Glock about "Glock Perfection," or CZ about their "most widely used handgun" claim... I would be skeptical of any response. I'd rather hear from someone who used or has tested the weapons, is unbiased and doesn't have a dog in this technical discussion/fight. Do you know of any such person or group? Or a source for some a head-on evaluation? Participants here sometimes seem to uncritically rely on claims and advertising points from the manufacturer on many issues.

Reviewing the available information from the original DoD Pistol Competition isn't particularly revealing. Lots of information out there about the guns makers that didn't compete, and why S&W was wrongly kicked out of the competition, but not much about the actual observed performance of the weapons from the two firms that did compete: SIG and Beretta.

I also found some General Account Office reports on the claims and counter claims following the award of the contract, and their (the GAO's) analysis of number of slide, frame and one barrel failure as the Berettas were being field tested by the Army and Navy after acceptance. All of those problems were quickly resolved.

I believe that the Berettas are just as reliable as the other guns that were then or are now considered Beretta's competitors -- S&W, SIG, Glock, CZ, H&K, FN, and maybe Ruger or Steyr -- but have seen nothing to make me believe Berettas are MORE reliable, in regard to ejection or any other area of function or performance.

Do you have evidence that supports the claim that they are more reliable, or are you just relying on input from Beretta's marketing machine?

[Walt Sherrill]

Afterthought...

In doing some related reading on the 'net, I found that Clint Smith (of Thunder Ranch), Bill Wilson, and Ken Hackathorn all think Berettas are among the most reliable guns.

Wilson may have a dog in that fight -- since he's selling "improved" Berettas, now -- but Smith and Hackathorn arguably don't. And, trying not to be snarky -- it could just be that Wilson is selling his upgraded Berettas because he thinks they're good, reliable guns that can be tuned to a sufficiently high level to carry the Wilson imprimatur.

I'm still not entirely convinced, but...that sort of feedback comes closer to the non-advertising-sourced info about reliability I've been looking for than what I've seen in these discussions.

.

[tipoc]

While it may be difficult to prove that the open top slide of the 92 is an aid to clean ejection it is most certainly true that it don't hurt it.

I encourage fellas to look at the slo-mo pics of the 92 ejecting.

A point about the Petter design lock up was made earlier in this discussion:

The reason pistols such as SIG and Glock have the oversized ejection port is the Petter improvement did away with the internal slide lugs of the 1911 and used instead a squared off barrel at the chamber to fit the ejection port. This accomplishes the same thing as the original internal slide and barrel lugs. This is really more of an ease in manufacturing than anything else, and has not one single thing to do with more positive or reliable ejection.

I believe the statement is true as far as it goes. Meaning that the Petter lock-up was not done with the purpose of increasing the size of the ejection port. But a larger ejection port does increase reliability by decreasing the possibility of port related jams.

The lowering of ports on 1911s began in the 1930s as part of custom touches for competition guns. This was one of a number of modifications done to increase reliability with a wider variety of loads beyond just ball ammo. The modifications evolved some over the years. Nowadays you buy a 1911 you expect a gun with a lowered and flared ejection port. The lowering helps reliability and the flaring largely helps reloaders I believe.

Many books and articles on custom work make this point, from Nye's old book, to Layne Simpson, Wilson, etc.

Jerry Kuhnhausen makes the point on page 133 of Vol. 1 of his manuals on the 1911:

"Enlarging the ejector port size, and thereby increasing shell clearance, is even more helpful, since the empty shell is guaranteed a completely unobstructed way out.

The combination of porting work, a well fit extractor and a positive ejector, virtually eliminates port related jams."

I think Beretta placed an open top slide on their gun because that's been their trademark look for decades. There is no actual evidence that it impairs functioning or reliability of the gun in harsh environments. It's done well in those. There may be no hard evidence that it aids in clean, trouble free ejection...but it certainly don't hurt.

It seems hard to build a gun in 9mm that does not function well. You'd likely have to put more effort into it to make a poor gun than the effort to make a good. The 92 is a good gun. It has no trouble jecting.

tipoc

[Walt Sherrill]

Originally Posted by tipoc

I think Beretta placed an open top slide on their gun because that's been their trademark look for decades. There is no actual evidence that it impairs functioning or reliability of the gun in harsh environments. It's done well in those. There may be no hard evidence that it aids in clean, trouble free ejection...but it certainly don't hurt.

If a larger ejection port to help ejection were the sole reason for it's existence, it could have been done with a much less open slide... just extending forward an inch or two more toward the sight. Let's assume it helps (maybe with stove pipes), which I think can still happen -- but does no harm.

I suspect that the point above, that the open slide has been a "trademark look for decades" may play a bigger role in the open slide's presence than most imagine.

Even the very early Beretta Model 1915 (left, immediately below), which had a conventional ejection port, had the open slide... But the M1923 (to right of the M1915) Beretta went whole hog. I'm not sure that all subsequent Beretta semi-auto shared that features, but many of them did. Maybe it IS a trademark look!



Browning, the Marketing firm, importer, and sometime gun-maker (and not John Moses B.), apparently didn't consider the open slide to be critical. Their version of the Beretta design, the BDA in .380, had a conventional slide -- but no reputation for being a jam-prone gun. The Beretta is to the left, below, and the Browning on the right.

[Limnophile]

Heck, you went to the trouble of finding that link, why didn't YOU ask them and share their response, here?

I almost did, but the need to register and expose my e-mail to further spam stopped me.

I did find a link to a recent Army Times article preview where Beretta is saying the Army never passed on any concerns about the open-slide design, and indicating that they regard the design as integral to the pistol's proper function, but one has to subscribe to read further. There must be a reason for the design, as it has been used across multiple models in several calibers for decades. I assume Beretta would be happy to share its reasoning. Whether or not such reasoning makes sense would be up for debate, unless they also had and were willing to share empirical evidence of prototype performance with and without the open-top slide.

[Limnophile]

it could just be that Wilson is selling his upgraded Berettas because he thinks they're good, reliable guns that can be tuned to a sufficiently high level to carry the Wilson imprimatur.

I read an article (sorry I didn't save the link) about the US Army Pistol Team shooting highly modified M9s in bullseye competitions. The modifications appear to take great skilled labor, but usually yield a pistol that shoots sub-1.5-inch, 10-shot groups at 50 yd. Isn't that a bit better than what a typical M1911A1 modification can achieve? One of the modifications involves removing a bunch of mass from the hammer to prevent the force of the hammer drop from driving the muzzle downward.

I was under the impression that the Army Pistol Team was still shooting modified M1911A1s. That they are using M9s seems to attest to they're quality.

[Walt Sherrill]

Originally Posted by Limnophile

I read an article (sorry I didn't save the link) about the US Army Pistol Team shooting highly modified M9s in bullseye competitions. The modifications appear to take great skilled labor, but usually yield a pistol that shoots sub-1.5-inch, 10-shot groups at 50 yd. Isn't that a bit better than what a typical M1911A1 modification can achieve? One of the modifications involves removing a bunch of mass from the hammer to prevent the force of the hammer drop from driving the muzzle downward.

I was under the impression that the Army Pistol Team was still shooting modified M1911A1s. That they are using M9s seems to attest to they're quality.

I've seen a number articles over the years, some photo heavy, about the Marksmanship Unit Pistol Team's guns -- and the gunsmiths who built them. (They shoot anything from .22s to custom shotguns...)

The Army put a LOT of custom work into those guns -- and I suspect the same effort put into any reasonably well-designed gun would give very good results. The Marksmanship Unit has been using Berettas for a long time -- beginning not too long after Berettas became the standard handgun for most Army personnel. The inserted dialogue below shows that it took the AMU's gunsmith over a full year working on nothing else to get the guns about where they should be. Think about that: it would have been bad ju-ju image-wise for the Army to use anything else, i.e., "we think the M9 is great for our soldiers in combat, but we use X when we're competing internationally..."

There have also been a number of articles in various gun mags over the years about the Army gunsmiths -- some of whom have retired and who now create custom guns, Berettas among them, for the civilian market.

Here's a link to an interesting discussion about the AMUnit's Berettas and what was done to make them so darned accurate. Much of it is top-notch gunsmithing, and that's probably a big factor in the gun's performance. As to the Beretta's fundamental accuracy: The P226 was also in the competition, and had it been accepted, I would expect something at least as good as the P-226 X-Five in 9mm to have come out of the AMU's gun shop. The AMU's gunsmiths could probably make a Hi-Point (which can be surprisingly accurate) look like a world-class gun, too. It would probably still be ugly, though.

More than the gun, I think it's the shooters and the gunsmiths that really make the difference when it comes to the AMU's stellar performance.

Here's a link to a discussion on another forum that is the source for the citation, below. It is the source of the quoted material, below. It addresses the gunsmith's role in the unit's performance. http://forums.vwvortex.com/showthrea...215&viewfull=1

Though Master Sergeant David E. Sams’ modifications to the Service M9 were developed for exclusive use by the AMU, it is interesting nonetheless to see what can be done to the Beretta to make it shoot.

Let’s skip the main course for now and get to the dessert: A tricked-out AMU M9 shoots 0.875-inch groups at 50 yards with factory match ammo. That’s right. Just over 1.5 MOA from a handgun. Even the best 1911s shooting tweaked handloads can’t do better, and most .45s can’t approach that level of accuracy.

What’s the secret, and why hasn’t anyone else been able to work out the Beretta’s bugs to this level?

“You’ve got to give full credit to the Marksmanship Unit,” the 39-year-old Sams said. “The unit commander called me into his office and told me to make the M9 fit for competition. About a year later, it was ready. But I didn’t have to work on anything else, and I could order or build whatever it took to get the gun right. I can’t think of a commercial gunsmith who could dedicate a full year to a single project. They’ve got to eat.”

Its a good discussion with a lot of details in the responses. The key question asked but not directly answered is "why hasn't anyone else been able to work out the Beretta's bugs to this level?" Good question: why haven't others also done so?

Sams, the AMU gunsmith above, apparently had a no-limits budget and no time constraints. Even the best (for profit) custom gunsmiths don't have that much freedom to improve a gun -- it can take them YEARS of testing and innovation to get there from here, and as Sams notes above, they've got to pay the bills in the meantime.

It looks as though Bill Wilson (of Wilson Combat) is giving some thought to the Berettas. Note, too, that Bruce Gray has already addressed the P226 (and other P-series guns, including the P320.)

David Sams, the gunsmith mentioned above, is now retired and offers his services to the public. Here's a link: http://www.samscustomgunworksusa.com/

[tipoc]

A bit more on the AMU Beretta:

http://www.gun-tests.com/pdfs/1-4-berettamods.pdf

tipoc

[Mike Irwin]

As far as I can tell, Beretta wasn't the first to use an open slide design.

The Mauser 1910 used an open slide design.

[B.O.F.H.]

The open slide design does make it easier to load individual rounds by hand should magazines be lost or damaged. Beretta literature also states that the extractor is designed to accomplish this feat. So, the most commonly used benefit of this design is direct chamber loading, think +1 without topping off the mag.

Also, I have an older Book of Beretta by Massad Ayoob in which he states that Bill Wilson recommends the M9 for out of the box, no time to test, reliability. Copyright 2005, at least a decade before he had skin in the game.

I am also of the mindset that the open slide design allows dirt and debris to clear the weapon while the locking block/ pistol action is buried safely in the frame.