Design, Function, and Repair
This week I started on the core of the course. One of the things emphasized heavily in this course, according to the introductory material that I reviewed last week, was the essential of design, function, and repair (DFR).
Design, Function, and Repair (DFR)
To be anything more than a rudimentary parts swapper, you have to have a complete understanding of how the firearm was designed to work, how it functions, and what your courses of action are to make any sort of repairs or changes to it. Without understanding the design, it’s just a black box that works magic when you pull the trigger. Very few firearms are so simplistic that you can instantly understand why things are designed the way they are. In fact, many firearms are literally works of art. The ability to see and understand how the parts fit together and their relationship in a three dimensional space is a critical skill.
This is where I found AGI’s cutaway views inside of functional firearms to be invaluable. It amazes me how sensitive some of these parts. Changes of only a few thousandths of an inch can have a huge impact on the reliability or whether or not the firearm even functions. This is also where I wish that there were some three dimensional depictions or animations of the parts, but I suspect that if/when these videos are updated, that will make it in. In the meantime, the primary instructor– Bob Dunlap– does very well at explaining the “how” and “why” using these cutaway views, disassembled parts, and working firearms.
Single Action Pistols
The course starts with the study of single action semi-automatic pistols and opens with the venerable Colt 1911. John Moses Browning was a genius, and most modern firearms are based, at least in part, on his designs. I own several of these pistols. While they are not my absolute favorite (the Browning Hi-Power holds that spot), they are very good and still very popular.
It was while viewing this section of videos that I began to understand what Gene Kelley saw in Bob Dunlap. The man’s knowledge is amazing. I took the statement that he made in the introductory videos about working on multiple hundreds of thousands of guns with a grain of salt. However, after having sat through only 10 hours of classroom with him, I have no doubt about that now.
Back in College
When I was in college, I had a professor who taught a course in “Rotating Electrical Machinery”. This was a course that dealt with large, powerful electric motors and the complex calculations that were required in their design and maintenance. The instructor was one of the toughest instructors I had ever had. He changed books every year so there was never a compendium of questions/answers circulation through the campus. Additionally, he assigned every homework problem there was and never even looked at the book while teaching. He knew it all by heart. Where we looked at the formulas as disjointed, he could derive one formula from another and link them all together.
He really knew his stuff. When it came time for tests, he never gave partial credit at test time, and his tests were often only four questions long. It wasn’t uncommon to totally fail his course. Yet, afterwards, you could set a meeting with him and walk him through your thought process where he would point out your errors and you would then get partial credit on the question. He was the most accessible professor I every had. At the time, I literally hated him and his class. When I made it out into industry, he was the professor that I respected the most. There was no slacking there, and I learned more from him about his subject matter than any other professor from their respective areas.
Bob Dunlap reminds of that guy. He knows his stuff forward and backward and is very proficient at teaching it.
This week was spent entirely on the Colt 1911, beginning with the field stripping of the gun and then progressing to the complete takedown and dissasembly. I was very impressed with the detail given as Bob took them apart, carefully explaining what each part was and how it functioned. Bob then moved to the aspects of working on the 1911. He identified what types of problems are common and how to fix them. Great detail was given when dealing with modifying parts and how tiny modifications can make the difference between just working and working well.
Bob spent considerable time on trigger jobs for the 1911. This is one of the most requested modifications and one of the most messed up operation by many gunsmiths. If you don’t understand exactly how the relationships work, you can get in trouble, as I’ll explain below.
One other notable addition to this section was where Bob explained how you can use the methods that Sig uses on their firearms to make the 1911 a very accurate firearm. It’s not even difficult to do. This is something that I’m putting on the project list for all of my 1911s and Brownings.
Impressions of Video
Some of the teaching obviously occurred in a classroom with an audience, though the production crew did an admirable job of keeping classroom noise down. I can hear some faint machining noises in the background and an occasional door opening and closing. However, for the most part, those noises are not a distraction at all.
Some of the teaching also takes place in a different setting where its pretty obvious that there were no students attending, as it was more of a studio type arrangement. In these settings, Bob’s hair is grayer, so I know they were recorded at a different time. That tells me that these videos have been remastered at least once to update and improve them. That’s good to know. I’m not buying something that is old and outdated. They are willing to update when they needed to.
The audio in the DVDs is mostly excellent. There are a few places where there is some fading in and out, like you would expect when a battery is dying on a wireless mic, but nothing is lost in the conversation and it only happens occasionally. There are also a few places where the audio track picks up a distracting buzz but not for long periods of time.
The most annoying aspect of the videos has to do with how they are played. The original videos are obviously in NTSC format and then transferred to DVD at a later time (whenever AGI made the transition from VHS tape to DVDs). In the transfer process a common error pops up. If you’ve ever had an old VHS tape remastered to DVD, I’m sure you’ve seen this issue. During the age of analog cathode-ray tubes (CRTs), everything was analog and there was some variance in how the video image was presented in the video frame.
To accommodate for this, manufacturers used a process called overscan. They would add additional lines of resolution to the video frame and the very edges were thrown away by your TV, presenting a decent picture to you. On modern digital equipment, the monitors no longer use overscan, and every line of the scan is often shown. The original intention was to have these extra lines as black, but manufactures of equipment often took shortcuts and they are just filled with noise.
On the course videos, these lines are readily apparent at the bottom of the screen. When they converted to DVD, they probably should have had the system replace the noise with black and then no one would notice. Instead, you have to learn how to ignore that noise. It’s not much. However, since it’s not black, it is noticeable.
The camera often switches to a closeup view of Bob’s hands while he is explaining something and if necessary, they will use an inset of the closeup while still showing Bob. Bob also obviously has a monitor that he is looking at and he can move around to give the best view of the closeup he wants. Using this method is almost as good as using computer animations to show the inner workings of the parts.
To keep you from getting bored on long segments of talking, the videos will switch between two cameras. It’s a common technique in the video production world and works well. Sadly, the two cameras used in this method, on the original classroom videos, are not color matched. You may not notice this, if you don’t do any video editing. It was mildly irritating to me, but it doesn’t happen very much. The content was well worth it.
AGI provides you with a set of notes complete with pictures on important aspects of the classroom lecture. Don’t depend on these notes for the tests though. While the information in them is useful, you won’t be able to just read the notes and then take the tests. You are going to have to watch the videos (sometimes more than once) to be able to pass these tests. The tests don’t try to trick you, but they are probably the closest I have seen to making sure you actually paid attention to the lecture from any others I have taken.
It’s pretty obvious to me that my initial anticipation of only 10 hours per week of classroom time is pretty optimistic. I’m still trying to stick to covering 10 hours of video. Yet, I often find myself rewinding a certain section or rewatching entire chapters again, either because I missed something or because I can see that there are critical ideas being talked about and I want a complete understanding of them.
It’s also readily apparent to me that you can’t just watch the videos. You must be working on the firearms. If nothing else, you need to disassemble and reassemble them just to help drive home the “design” and “function” aspects of the course. An FFL is going to be a necessary thing to gain access to firearms unless you have enough friends and family to keep you supplied well.
While the Browning Hi-Power won’t be covered until next week’s videos, all of my Colt 1911s were functioning fine. I disassembled and reassembled the Colts several times and then decided to tackle my Hi-Power, since they were so similar. I was dismayed at what I found though.
Dangerous Carry Condition
Bob spent a significant amount of time detailing how the sear/hammer system worked, especially when dealing with improving the trigger pulls. I was disturbed to find that the sear/hammer relationship in my own carry gun (a Browning Hi-Power in .40S&W) was wrong. The sear had a negative relationship. While the trigger pull was about six pounds, it was creepy and had a tendency to creep forward. That makes it insecure if the gun receives any significant vibration. While I carry it with the safety on, I have occasionally found the safety swiped off by accident. It’s possible that the gun could discharge if the right conditions present itself with that negative sear relationship. That will be something that I have to address. That firearm is now temporarily retired until I fix it.
That worked out though, because I have a Bar-Sto 9mm conversion barrel that I want to fit to the gun. I had already worked on the lockup and was comfortable, but the barrel didn’t quite fit. The slide had a tendency to stick open when it cycled, requiring the barrel to be bumped to allow it to return into battery. Bob covered fitting the barrel for lockup but not the problem I was experiencing. This gave me the opportunity to contact the AGI office and speak with Jack Landis on how to fix this problem. In about five minutes, he walked me through the process of finding out where it was binding up and how to correct it.
My Own Disaster
Using his directions, I located the area where the barrel was binding in the slide and then grabbed my Dremel with a sanding drum to lightly touch-up the area of concern. The Dremel spun up. I triple checked everything and touched the drum to the barrel and knew instantly that something was horribly wrong. It could be that the Dremel was bad, the mandrel was bent, or even that that particular sanding drum was incorrectly made, but in the first pass, I set a wonderful wave pattern into the barrel as the drum bounced all over the place. Argh!!!
After calming down, I got on Amazon and ordered a Foredom TX rotary flex shaft tool and a set of bits for it. That project will be shelved until the tooling comes in. That’s my tool for the month. I hadn’t intended on getting one yet, but it’s pretty obvious that I needed one. I could have just used files and probably done just fine, but I was going to eventually get one so why not now.
Resources and Tools
Aside from the Foredom rotary tool, I picked up a copy of R.D. Nye’s “45 Auto Custom Touches” from eBay. It appears to contain much of the same information that Bob covered with many accurate drawings showing the relationships between the parts that Bob talked about and with cutaway views. I think it’s going to be a pretty good complement, though Bob’s information was more comprehensive.
Gun Club Update
Last week I mentioned the Gun Club of America. This week I spent some time looking through more of thei Guntech videos and publications as well as took some time reading the forums. The early videos are 4:3 aspect converted from NTSC format, but the later videos are all HD formatted. That’s good to know that they have improved their productions. I’m sure as they update their course, we’ll see more HD stuff, but it will be really hard to replace the original videos of Bob. I’m willing to live with the limited resolution due to the content.
I should also note that in one of the Guntech videos I watched, Jack Landis mentioned that if you are a Gun Club of America member or a student of AGI, you can call the office and get a pretty good price on the Foredom tools. They buy them in bulk for their Enhanced Master Gunsmith Course.
I’ll see you next week when I finish up the 1911 instruction and the Browning Hi-Power is covered along with double action automatics.
The American Gunsmithing Institute (AGI) is a DVD/distance learning educational source that specializes in gunsmithing. They offer programs in professional and practical gunsmithing, welding, machine shop including instruction on the lathe, vertical mill and general machine shop. In addition to the complete gunsmithing course, they also offer informational DVDs on specific firearms and armor’s courses for some popular firearms. If you are interested in taking any of the courses or just learning about them, you can request information online or just call them at 1-800-997-9404.