How come more pistols don't have an open top slide like the M9?

[Degtyaryov]

It seems like a really great way to save weight, and if implemented on a modern polymer based gun could give a really lightweight final product. And if the M9 is .mil standard issue, it must not have too many issues with reliability. It looks like there'd be a lot of potential in that type of platform. Is there something I'm missing?

 

[gunman41mag]

I would say, that weaken the slide

 

[roadrunner681]

poly guns are ridiculously light already why do they need to be lighter? would that not increase recoil? i rather see a glock with no finger groves.

 

[87iroc]

From an engineering standpoint...the opening in the slide is being pulled open by the force of the gases so it carries no real load....if it was being pushed open from the front it might be a problem(but I doubt it too)...but being pulled would put less force on it I think.

On a polymer gun...not sure. Same principal applies but I can't foresee it being an issue either as a polymer gun still has a metal slide on it.

Not sure why the M9 does it...I have held one but never really looked at it torn apart.

 

[rvb]

most common pistols have the locking lugs that mate the barrel to the slide on top of the barrel. the beretta / walther design with the falling locking block allows the open-top design. The JMB designs of the 1911 and browning (on which the glocks/Sigs/M&Ps/etc are based) are considerably more durable.

From there it's a debate about whether the open-top design is better because it lets the cases eject easier or if it's worse because it allows in more debris.

There was a version of the M9 w/ a closed slide and std-looking ejection port.... quite rare. The "dolphin" slide, iirc. edit: from Phrobis.

http://www.justpistols.co.uk/dolphin_real.htm

-rvb

 

[JasonB]

Love the Thoughts behind Dolphin Slide, but it was never actually put in production...

Single Biggest drawback to M9/92 is lack of Front Barrel lockup similar to 1911's... Slide change that would fix this would be something I'm willing to hand over $$$'s toward for my 92's.

Second in line for M9/92's is easily resolved with about a $4 Wolf 13lb Trigger Spring... Oh and ~$50 for Sear/Hammer/Trigger Bar Polish.

 

[rvb]

Single Biggest drawback to M9/92 is lack of Front Barrel lockup similar to 1911's... Slide change that would fix this would be something I'm willing to hand over $$$'s toward for my 92's.

It can't lock up similar to 1911 since the barrel doesn't move vertically during lockup. The M9 locks up just fine in its own way, it's just different than the 1911.

Few people understand how the M9 locks up, so to most it's a "problem." The 1911 gets two points of contact at the muzzle since it can tilt down and "unlock" those two points during recoil. The M9 doesn't tilt so a similar system up front would just bind the gun up. The barrel of an M9 comes to rest at the bottom of the opening in the slide. This is its repeatable stop (most think it's just 'loose' and that not being centered is a problem, and blame it for their poor accuracy). The breech in the slide pushes forward on the barrel, causing the locking block to stop on the take-down lever. This causes the barrel to 'cam over' so the muzzle hits the bottom of the slide, and now the gun is locked up. If not for a place to hold the front sight, you wouldn't even need the top half of the front of the slide.

I competed with a 92 for many years. It's accuracy is on par w/ any mass production 1911 out there (not talking custom shops like les baer). I could ring an 8" plate at 75 yds about 80% of the time w/ just good sights and some trigger work.

The 1911 is better for "accurizing" and bullseye use, but not better in terms of the guns provided to the troops...

-rvb

 

[Birds Away]

I was surprised at this question. Most 92 owners I know complain about the slide. I can't imagine why anyone would want one like it. Could be just me.

 

[hrearden]

It can't lock up similar to 1911 since the barrel doesn't move vertically during lockup. The M9 locks up just fine in its own way, it's just different than the 1911.

Few people understand how the M9 locks up, so to most it's a "problem." The 1911 gets two points of contact at the muzzle since it can tilt down and "unlock" those two points during recoil. The M9 doesn't tilt so a similar system up front would just bind the gun up. The barrel of an M9 comes to rest at the bottom of the opening in the slide. This is its repeatable stop (most think it's just 'loose' and that not being centered is a problem, and blame it for their poor accuracy). The breech in the slide pushes forward on the barrel, causing the locking block to stop on the take-down lever. This causes the barrel to 'cam over' so the muzzle hits the bottom of the slide, and now the gun is locked up. If not for a place to hold the front sight, you wouldn't even need the top half of the front of the slide.

I competed with a 92 for many years. It's accuracy is on par w/ any mass production 1911 out there (not talking custom shops like les baer). I could ring an 8" plate at 75 yds about 80% of the time w/ just good sights and some trigger work.

The 1911 is better for "accurizing" and bullseye use, but not better in terms of the guns provided to the troops...

-rvb

Thank you. I havent seen any die without sustaining something which would not also kill a 1911.

 

[rvb]

Thank you. I havent seen any die without sustaining something which would not also kill a 1911.

I was just speaking in terms of accuracy from the guns. I think the locking system of the 1911 has better durability (less likelyhood of part failure) than the M9... however.... the improvements to the locking block over the years have closed that gap for sure.

M9 compared to GI M1911 (both w/ GI ball) I think the reliability (likelyhood of malfunction) is pretty even... 92FS compared to average commercial 1911s, I think the 92 is hands down more reliable. But that's not a function of the open-top slide, that's a function of magazine feed angle, adhearance to specs (with a 92FS you are getting a mil-spec slide with different roll marks, w/ a commercial 1911 you are getting some shops interpretation or re-design of the specs), etc.



-rvb

 

[cmamath13]

There was a version of the M9 w/ a closed slide and std-looking ejection port.... quite rare. The "dolphin" slide, iirc. edit: from Phrobis.

Just Pistols - The Truth about the Beretta Dolphin

-rvb

That's a damn good looking firearm!

 

[indyjohn]

That's a damn good looking firearm!

Olive Drab, eh? I'd [STRIKE]hit it[/STRIKE] have it as my EDC..

 

[85t5mcss]

It seems like a really great way to save weight, and if implemented on a modern polymer based gun could give a really lightweight final product. And if the M9 is .mil standard issue, it must not have too many issues with reliability. It looks like there'd be a lot of potential in that type of platform. Is there something I'm missing?

Glock 34, 35, 17L, 24 but these are the competition length and have longer slides. They are out there but just not required or needed as mentioned in other posts.

Not sure if it would be more costly in the manufacturing process or not since it would need milled out vs. cast