1911s - Some Thoughts

[BLR]

Objective: begin dispelling myths and misconceptions about short recoil operated pistols, and 1911s in particular.

Requests from the Author: Please do not quote authorities of the 1911 out of context. If they care to chime in, great. Chances are they are simplifying an observation and quoting them will not do justice to their insight. Please don’t simply say “my experience with 1911s has been poor.” It adds nothing to the discussion. In other words, I’m going to spend more than a few “unbilled” hours on this, so please don’t turn it into every other 1911 thread out there.

I stated previously that for Browning Tilt Barrel Short Recoil Operated pistols, the magazine is the primary concern. For background, and to dispel Myth 1 (1911s have a more torturous feed path), please consider the following pictures. Picture 1 is of a Sig P220 with current generation magazines.



Picture 1. Sig P220 Feeding Angle

Notice the nearly horizontal angle of the round in the magazine. I don’t believe anyone will argue that the P220 isn’t a reliable design and I’ve never heard anyone say it had a difficult feed path or that it was the “King of the Feedway Stoppage.” Now let us take a look at a Colt. First up, in Picture 2, a typical 7 round magazine with tapered feed lips.



Picture 2. Colt S70 of Recent Manufacture and a 7 Round Magazine of Recent Manufacture

Now it seems appropriate to look at a more modern magazine. In Picture 3, a Wilson ETM is shown in the same Colt S70.



Picture 3. Colt S70 of Recent Manufacture and an 8 Round Wilson Combat ETM Magazine

Obviously, there is no indication in these pictures of a more tortuous feed path when compared with a Sig P220. There does exist a distinct and significant difference between a P220 mag and even an ETM mag. For the sake of argument, lets carry this line a bit further before broaching that difference. In Picture 4, the “Benchmark of Modern Design and Reliability” – a 3rd Generation G17 with a factory magazine.



Picture 4. 3rd Gen G17 with Factory 17rd Magazine

I don’t believe that to be a significant improvement in cartridge position over the 7 round 1911 combination, but that begs the question – What is significant? Picture 5 is of a “Short Extractor” P226 Elite Dark, using factory (MecGar) magazines.



Picture 5. Sig P226 Elite Dark with Factory Magazine

Picture 5 shows similar position relative to the chamber as the G17 in Picture 4. Picture 6 shows a MkIII P35 with a factory (MecGar) 13rnd magazine.



Picture 6. MkIII P35 with Factory 13rd Magazine.

Finally, Picture 7 shows a Beretta M9A1 with the new PVD coated magazine.



Picture 7. Beretta M9A1 with PVD Coated Factory Magazine.

As can be seen, the largest departures of magazine position to chamber position are with the P220 and the M9A1, both highly regarded for reliability. By logical conclusion, another factor(s) is at play.

First, let us see if we can agree on a principal of mechanical reliability. That is reliability a function of consistency. If the ammunition is identical round to round, the firearms operation (excepting the magazine) identical round to round, the firearm is held the same, then reliability must stem from the magazine. That is not to say reliability is a function of the magazine and magazine alone, but we must understand the components before the system. In that light, it seems appropriate to look for indications of variation in how the round is presented to the feedramp/chamber. Picture 8 shows the feedramp of a 10mm Nighthawk Custom Falcon using the factory 8 round magazine (Checkmate welded base) and fresh recoil spring and Hornady 155gr factory loads.



Picture 8. NHC Falcon in 10mm Feedramp Markings

Inspection of the feedramp indications inconsistent presentation of the round. The firearm to date has been reliable. Figure 9 shows the feedramp of a Springfield Armory Professional Model of recent manufacture using “tuned” Wilson ETM magazines and 200gr LSWC ammunition.



Picture 9. SACS Professional Model with Tuned ETM 8rd Magazine

As can be seen in Picture 9, a much more consistent, higher in position to the bore centerline mark can be seen. To investigate this further, 4 Wilson ETM 8rd magazines were modified with new followers, base plates, and springs (springs were stock, but tuned to modify the load distribution on the followers). The result is shown in Figure 10.



Picture 10. Wilson CQB (WCOO range) using Modified ETM Magazines.

As can be seen in the Picture 10, nearly no contact with the feedramp is indicated. Picture 11 shows the same magazines used in the S70 Colt from above.

[BLR]

Picture 11. S70 Colt using Modified ETM Magazines.
To contrast this, Picture 12 shows the feed ramp of the M9A1, clearly showing contact points on the barrel as well as the frame cut.



Picture 12. Beretta M9A1 using Factory PVD Magazine.

[Super77]

Bill thanks for your posts. This is an interesting topic that doesn't get as much attention as it deserves. Is there a way to quantify the different factors at play here to find out which really matter? There are obvious ones such as the cartridge angle as it sits in the magazine and the distance from the top of the mag to the bore line. I also notice different designs place the tip of the cartridge at varying distances from the breach. Does the angle at which the barrel tilts to unlock from the slide affect consistency across different pistol designs? I know you're intent was to keep this 1911-centric but there's a fair amount of variation even within that species. Unlike say Glock pistols there are a number of aftermarket magazines available for 1911s that have design tweaks meant to improve on the original. For instance I seem to remember that Tripp Research CobraMags supposedly have modified feed geometries. Do you have any insight on how manufacturers tweak the original design to improve feeding?

[JHC]

In the other recent thread you said the BHP had the best orientation. What makes it so? The Sig seemed most direct into the chamber.

Pretty neat thread already.

[BLR]

Bill thanks for your posts. This is an interesting topic that doesn't get as much attention as it deserves. Is there a way to quantify the different factors at play here to find out which really matter? There are obvious ones such as the cartridge angle as it sits in the magazine and the distance from the top of the mag to the bore line. I also notice different designs place the tip of the cartridge at varying distances from the breach. Does the angle at which the barrel tilts to unlock from the slide affect consistency across different pistol designs? I know you're intent was to keep this 1911-centric but there's a fair amount of variation even within that species. Unlike say Glock pistols there are a number of aftermarket magazines available for 1911s that have design tweaks meant to improve on the original. For instance I seem to remember that Tripp Research CobraMags supposedly have modified feed geometries. Do you have any insight on how manufacturers tweak the original design to improve feeding?

Yup! Kinematics. Factors include static and sliding friction of the round in the magazine and on the feedramp, position and attitude departure, and distribution of spring pressure along the cartridge/feed lips.

First, a definition of the problem needs to exist, and I don't think one exists. Then definition of the design operating envelope (min/max allowable friction, angles, etc), which I know doesn't exist.

I'm unaware of a magazine design for the 1911 that was approached scientifically.

Like I said, it's all about the magazine. In so far as the how of tuning? In a later post. I think we, as in all of us, need to reach some common ground first.

[BLR]

In the other recent thread you said the BHP had the best orientation. What makes it so? The Sig seemed most direct into the chamber.

Pretty neat thread already.

Yep, orientation means more than initial position relative to the chamber, though.

[45dotACP]

Very interesting! I have always wondered about whether or not it was a bad thing for a 1911 to "nose dive" when feeding. It was my understanding that it was necessary for the bullet to strike the frame ramp, which was angled just such that the cartridge will "bounce" into the chamber. Seems to be the case with a couple of more modern guns too. My personal Caspian has strike marks all over the frame ramp. Never has had any problems with feeding the rounds other than when the rounds are loaded too long and hit the slide stop lobe and locked the gun open. But there have never been any feedway stoppages with factory ammo...

[JodyH]

Please don’t simply say “my experience with 1911s has been poor.” It adds nothing to the discussion. In other words, I’m going to spend more than a few “unbilled” hours on this, so please don’t turn it into every other 1911 thread out there.

"Let's not turn a thread that's already just like every other 1911 thread into every other 1911 thread".
Ok... Thank you for not billing us for this information.

[BLR]

Very interesting! I have always wondered about whether or not it was a bad thing for a 1911 to "nose dive" when feeding. It was my understanding that it was necessary for the bullet to strike the frame ramp, which was angled just such that the cartridge will "bounce" into the chamber. Seems to be the case with a couple of more modern guns too. My personal Caspian has strike marks all over the frame ramp. Never has had any problems with feeding the rounds other than when the rounds are loaded too long and hit the slide stop lobe and locked the gun open. But there have never been any feedway stoppages with factory ammo...

That's not a good thing.

And that highlights a number of issues and misconceptions around the 1911. The cartridge need not, and should not, bounce around when feeding. It should be fed in a controlled manner, just like a P30 or G17 or P226. After all, functionally, they are identical mechanisms. All short recoil magazine fed designs, right?

Marks all over the feed ramp (typically) indicate different motions for the 1st, 2nd, 3rd, and so on, round. I would expect that if you fed just the top round in a full magazine, then just the last round in a magazine, you'd have two distinct marks on the feed ramp at the extremes.

[45dotACP]

That's not a good thing.

And that highlights a number of issues and misconceptions around the 1911. The cartridge need not, and should not, bounce around when feeding. It should be fed in a controlled manner, just like a P30 or G17 or P226. After all, functionally, they are identical mechanisms. All short recoil magazine fed designs, right?

Marks all over the feed ramp (typically) indicate different motions for the 1st, 2nd, 3rd, and so on, round. I would expect that if you fed just the top round in a full magazine, then just the last round in a magazine, you'd have two distinct marks on the feed ramp at the extremes.

I'll try what you suggest. It might be the result of all the various different brands of 8 round magazines I use