Just when I thought I was over 1911's.....

[Tuesday]

The standard (i.e. small) radius firing pin stop is a reliability feature. The leverage disadvantage absorbs more of the impulse of the slide at the beginning of the slide's travel, sparing the extractor compared to a heavier recoil spring, which slows the slide as the slide moves rearward.

Because of Newton's third law—for every action there is an equal and opposite reaction—you cannot reduce recoil, regardless of what you think you feel, by changing (effecrive) spring rates. At most you'll change when you experience the recoil impulse during the cycling of the pistol.

[farscott]

The standard (i.e. small) radius firing pin stop is a reliability feature. The leverage disadvantage absorbs more of the impulse of the slide at the beginning of the slide's travel, sparing the extractor compared to a heavier recoil spring, which slows the slide as the slide moves rearward.

Because of Newton's third law—for every action there is an equal and opposite reaction—you cannot reduce recoil, regardless of what you think you feel, by changing (effecrive) spring rates. At most you'll change when you experience the recoil impulse during the cycling of the pistol.

I am not sure I am following you. The larger the radius applied to the bottom of the firing pin stop, the higher on the hammer the firing pin stop impacts. That allows the hammer to experience more applied torque for the same given slide force (mass times acceleration). So providing a larger radius to the firing pin stop makes cocking the hammer easier. For the flat-bottom firing pin stop, the slide needs to provide more force to cock the hammer as the force is applied closer to the hammer's center of rotation. Another way to think about it is that there is a given amount of torque needed to cock the hammer, and there are several variables that can be changed to adjust that torque. One variable is where the torque is applied, another variable is slide acceleration, and a third is the mainspring spring constant. A fourth would be the recoil spring constant. There are other variables, including how the barrel bushing is fitted, but the four listed are the primary ones. The variable we are discussing is the torque. The initial reason for the radius was to make loading easier when starting with the hammer in the at rest position.

Since cartridges that have more recoil energy (same slide travel, so has to be more force, so more acceleration as slide mass is constant) apply more recoil acceleration to the slide, it makes sense to use a smaller radius on the firing pin stop. The same amount of torque is applied to cocking the hammer, but more of the slide's rearward travelling energy (force * distance) is needed to cock the hammer. That makes the gun's perceived recoil seem less as the slide is using more energy to cock the hammer than it would with the "standard".

It is also the reason why a flat-bottom stop should not be fitted on a 9x19 pistol as the amount of acceleration provided by the 9x19 round is already marginal for the 1911 design. My 9x23 gun also has a barrel fitted with a Kart 9x19 barrel. To use the same firing pin stop and mainspring from the 9x23 with the 9x19 barrel, the recoil spring is a 9# unit and the gun is hard chromed to decrease frictional losses. The 9x23 barrel uses a 18# recoil spring. While perceived recoil with the 9x23 is more than the 9x19 barrel, most shooters feel it is similar to a standard .45 ACP, even though the 9x23 energy is much more.

[Tuesday]

I am not sure I am following you. The larger the radius applied to the bottom of the firing pin stop, the higher on the hammer the firing pin stop impacts. That allows the hammer to experience more applied torque for the same given slide force (mass times acceleration). So providing a larger radius to the firing pin stop makes cocking the hammer easier. For the flat-bottom firing pin stop, the slide needs to provide more force to cock the hammer as the force is applied closer to the hammer's center of rotation. Another way to think about it is that there is a given amount of torque needed to cock the hammer, and there are several variables that can be changed to adjust that torque. One variable is where the torque is applied, another variable is slide acceleration, and a third is the mainspring spring constant. A fourth would be the recoil spring constant. There are other variables, including how the barrel bushing is fitted, but the four listed are the primary ones. The variable we are discussing is the torque. The initial reason for the radius was to make loading easier when starting with the hammer in the at rest position.

Since cartridges that have more recoil energy (same slide travel, so has to be more force, so more acceleration as slide mass is constant) apply more recoil acceleration to the slide, it makes sense to use a smaller radius on the firing pin stop. The same amount of torque is applied to cocking the hammer, but more of the slide's rearward travelling energy (force * distance) is needed to cock the hammer. That makes the gun's perceived recoil seem less as the slide is using more energy to cock the hammer than it would with the "standard".

It is also the reason why a flat-bottom stop should not be fitted on a 9x19 pistol as the amount of acceleration provided by the 9x19 round is already marginal for the 1911 design. My 9x23 gun also has a barrel fitted with a Kart 9x19 barrel. To use the same firing pin stop and mainspring from the 9x23 with the 9x19 barrel, the recoil spring is a 9# unit and the gun is hard chromed to decrease frictional losses. The 9x23 barrel uses a 18# recoil spring. While perceived recoil with the 9x23 is more than the 9x19 barrel, most shooters feel it is similar to a standard .45 ACP, even though the 9x23 energy is much more.

Leverage is the same as torque here. Calling it one or the other makes no difference whatsoever. The hammer cocks only the first little bit of slide travel and has relatively little effect on the slide thereafte. The hammer requires constant force to cock, regardless, because the down and fully-cocked/positions are the same regardless. The larger the FPS radius, the more leverage the slide has on the hammer, the more leverage the more distance required to cock the hammer, and thus greater initial slide velocity, but no substantive difference once the hammer is cocked.

The rest of the factors are irrelevant because we're obviously considering all other factors equal.

And unpacking it at the other end works the same way. Your feelings are a lie. You're getting the same recoil impulse.

[BWT]

It requires more leverage or atleast a longer duration because the slide takes more time and/or energy to unlock.

Then again, maybe John Moses Browning was a moron and made the change and the US Army didn't know how trust their lying eyes.

This isn't some dude talking about his snake oil. The change was made to ease the process of cocking the hammer by a man that revolutionized every version of small arm known to man.

I'd be careful to call people liars over a Flat Bottom Firing Pin Stop. Especially when there are literally millions of examples of that firearm floating around and it's been around over 100 years.

God Bless,

Brandon

[StraitR]

Well, I thought and thought about grabbing a basic blue Colt in .38 Super or 9mm... but went with another pizza gun instead. A 92 Compact in this case.

Normally, I would FULLY support and applaud that decision, but right now all this PF 1911 talk has given me the withdrawn shakes. I can't decide if I want to take a chance on the new Colt LW Commander 9mm or sell off six pistols and get a Wilson Combat Ultralight Commander 9mm.

YIKES!

I can't find much on the new 9mm Colt LW Commander.

[Jared]

Normally, I would FULLY support and applaud that decision, but right now all this PF 1911 talk has given me the withdrawn shakes. I can't decide if I want to take a chance on the new Colt LW Commander 9mm or sell off six pistols and get a Wilson Combat Ultralight Commander 9mm.

YIKES!

I can't find much on the new 9mm Colt LW Commander.

What would you like to know about Colt's new 9mm LWC?

[StraitR]

What would you like to know about Colt's new 9mm LWC?

10-8 performance extractor test results?
Extractor fit
Barrel fit (link, hood, bushing)
Bushing to slide fit
Small parts fit (i.e. loose safety/beavertail)
Slide to frame fit (not end of the world, but curious)
Obvious defects

And the typical stuff...

Functionality issues, Round count, failures, parts breakage, what mags are working/not working?

I'm really interested in this Colt.

ETA: I found this article on 9mm vs. .45acp 1911's by Bill Wilson very encouraging.

[Totem Polar]

^^^watching...

[HCM]

Normally, I would FULLY support and applaud that decision, but right now all this PF 1911 talk has given me the withdrawn shakes. I can't decide if I want to take a chance on the new Colt LW Commander 9mm or sell off six pistols and get a Wilson Combat Ultralight Commander 9mm.

YIKES!

I can't find much on the new 9mm Colt LW Commander.

Split the difference and get a Dan Wesson Valkrye Commander.

[45dotACP]

I've got a 1991 series Commander in 9mm. I find that overall I like the gun, but there were a few things that irritated me after a bit.
-Extractor tension: Didn't pass the 10-8 test, but after a quick bend and checking the gauge, it does.
-Springing: The gun seems a bit heavily sprung for a 9mm.
-Barrel fit: The gun rides the link and the bushing is loose. It's accurate enough to stay in a USPSA A zone at 25 yards, but it's not quite as accurate as I'd expected. Will be adjusting with an EGW bushing
-Trigger: Was bleh, even for a 1911. Not on account of the Series 80 system, but it was just a bit heavier of a break than I expected.
-Mag catch: Not adequately relieved. 10 round metalform mags won't drop free and are difficult to insert.

I ended up replacing the rat tail beavertail and the rear sight with a 10-8, but the LW has a novak dovetail and a beavertail.

Not certain if these things would carry over the LW commander, but I'd probably suggest the DW if you're looking at a gun that doesn't need some finishing work.