2012 | Page 20 of 28 | Tennessee Gun

16 Apr 2012

How to Replace a CETME Roller

CETME Roller Replacement — Buy at Amazon

In previous articles we talked about the importance of bolt gap on delayed roller blowback rifles like the CETME or the HK G3s.

We even touched on how to increase bolt gap by adding oversized rollers to correct wear of internal parts.

What we did not do is give instructions for replacing the rollers.

Now, as I have said before, I am not a gunsmith, but I will present an easy way of changing rollers.

You don’t need much in the way of tools – a pair of pliers, a roll pin punch (I used a nail) and a hammer.

Procedure:

First ensure you have NO ammunition in the room. This is imperative to make a habit whenever you are cleaning, working on, or dry firing your firearm.
Next strip the rifle (we have an article on that)
Remove bolt assembly by twisting – you probably can do this without tools if you have decent hand strength
Remove Bolt head from Carrier (twist and pull)
On the top of the bolt head you will see a small hole with a roll pin. Using a small punch tap out the roll pin, I did not have a punch nearby that was the right size so I used a small finishing nail. Retainer plate and rollers will now slide out the side
Shake bolt head until the roll pin falls out.
Insert your plus sized rollers on the retainer plate (one side of the roller ill have a small divot in the center. This divot corresponds to a tip on the retainer plate.
Slide retainer plate and rollers back in the bolt.
Reinstall pin (may take a tap on the punch with a small hammer)
Reassemble firearm function check to ensure you put everything back properly
Check bolt gap (it should have increased) If it has not or it is still out of specification you may have to consider getting the barrel repressed – there are not a lot of gunsmiths that are willing to do this, but luckily I found two in my area.

Resources for CETME Parts

(I have no connections to any of these companies, but I have been their customer)

I buy my rollers from RTG International Surplus Parts in Arizona

And for barrel work, I use wither Dave’s Gun shop in Cookeville TN (I’ve been in firearms classes with Terry their gunsmith – great bunch of guys)

Or Lock Stock and Barrel in Franklin TN (sorry no website)

13 Apr 2012

Prepper Precepts #26 Don’t Waste. Be Frugal, Learn to Make Do, or You May Have to do Without

My adherence to this prepper precept causes fights at my house. It is Don’t waste. Be frugal, learn to make do, or you may have to do without.

You can’t always run to the store for parts and new stuff – learn to make do with the old. By being frugal and eliminating as much waste as possible you will become a better steward of your resources and will not only need much less, but you will save more. Turn it into a game and it will be much easier.

You will be surprised on how much you actually need once you learn and practice frugality.

Rules of Civility: The 110 Precepts that Guided Our First President in War and Peace

These precepts are my creed, and having prepper precepts guides me when I face tough choices. A wise man once told me that when facing a moral problem, the right choice is usually the action you don’t want to take.

I am not a pollyanna person that is wishy washy or blindly follows rules, heck I have a little rebellious streak and love to know the WHY of rules, but I do respect and understand the need for law and know how vital it is for a society to have a moral code.

By knowing what I believe in you can know how I will act. This is very important in times of stress. If you don’t want to read these precepts one by one, the completed list can be found here: Completed 27 Prepper Precepts.

11 Apr 2012

Handgun Scenario #2 Bank Robbery

This video is a handgun scenario clip from the old TN handgun permit video, it is being used under the fair use doctrine.

This video will show a brief encounter that a legally armed citizen will face.

Please watch it and then think about what you would do in this situation.

An armed citizen generally has an extremely compressed window in a use of force situation. If you have not spent some time seriously considering what would cause you to use force and the implications (Physical, Legal, Moral, Psychological, and Sociological) then you are setting yourself up for failure.

Consider your gut reaction and what you immediately think you should do. Then think about the implications of those actions and see if it changes your mind on what you should do.

Answer these two questions:

Would I have taken same action as the armed citizen in the video?
If I had, would it have been legal?

What was the “legal” response…

I think this kind of what would you do training is invaluable to preparing a person to carry a gun for self defense. If you never work on handgun scenario training you will have to work through the situation when it occurs – this will waste precious seconds and may cause you to do the wrong thing. Please look at the post on OODA loop for more information.

Go to the Next Page to See the Discussion Answer

10 Apr 2012

Ayoob on Shooting Aftermath

Knowing how to deal with what comes in a shooting aftermath – especially if your the armed citizen that fired a handgun, I can think of no better instructor than Massad Ayoob.

According to Wikipedia Massad Ayoob is an internationally known firearms and self-defense instructor. He has taught police techniques and civilian self-defense to both law enforcement officers and private citizens since 1974.

He was the director of the Lethal Force Institute (LFI) in Concord, New Hampshire from 1981 to 2009. Ayoob now directs the Massad Ayoob Group (MAG).

More than that bio Mr. Ayoob writes some of the best firearm books on the subject of the legal aftermath of a self defense shooting. I widely quote his work in my classes, and recommend his books courses and videos to my students.

I like to say I can teach anyone to shoot well, teaching the fundamentals of shooting is easy. It is the teaching of when to shoot and how to shoot when people are shooting back is what is hard. Special concern needs to be given to what happens AFTER a shooting. Dealing with the shooting aftermath is pretty important in its own right. After all you don’t want to go to jail for saving a life – not do you want to deal with grief, guilt or other emotional issues for it either.

9 Apr 2012

How to Measure CETME Bolt Gap

First off let me say, I am not a gunsmith. I am even less an expert on delayed roller blowback (DRB) rifles like the CETME or an HK 93. However, let me say that this post from military firearms.com does an OUTSTANDING job of describing what is going on inside your rifle.

If you’re not interested in knowing how it works and just want to know how shoot, my article will tell you what you need to know to ensure your CETME or G3 has proper bolt gap.

However, I would highly recommend you read the military firearm post by bladeworks123, because the more you know about your rifle the easier you will be able to keep it running.

Bolt Gap is Not Headspace

You need to know that there is a difference in bolt gap and headspace. Headspace is the distance measured from the part of the chamber that stops forward motion of the cartridge to the face of the bolt. This is important. If the headspace is incorrect, ammunition will not chamber correctly. Alternatively, it may rupture and cause damage to the firearm or the shooter.

In locked bolt guns like an AR-15 you can buy gauges that are machined to look like cartridges. The gun should lock up on a “go gauge” and fail to lock up on a “no-go” gauge. When a DRB rifle barrel is pressed into the receiver, it is not pressed to the face of the bolt. It is pushed even further so that the rollers in the bolt head are pushed against the locking piece. The locking piece is putting pressure on the bolt carrier creating a gap the bolt head and the bolt carrier.

Bolt Gap is Critical

This gap is critical. It is the point that the action is about to open. Consequently, it is the measurement that allows the rifle to function correctly. If the barrel is pushed in too far the action will open too soon. Alternatively, if the barrel is not pressed in far enough, the rollers will have to travel too far to unlock the gun. Since the back pressure from the gun’s firing may not last the full trip the gun probably won’t cycle. If it is extremely short than then portions of the neck of the cartridge will be unsupported and may rupture.

In a DRB a go or no-go gauge will both seat in the firearm. There is no true way to measure headspace in a rifle such as this, but the bolt gap measurement achieves the same result and is a more accurate measure of what you are trying to check.

Here is the procedure:

First, remove any magazine and check that the chamber is empty.
Perform the HK slap by pulling the charging handle to the rear and locking it. Then, slap the charging handle down with the palm of your hand sending the charging handle forward using spring pressure only. This is important to get a true measurement. Riding the handle forward may cause it to bind at the end of the cycle.
Pull the trigger so the hammer is down.
Invert the firearm so the empty magazine well is pointing up.
Next, open the feeler gauge up to .5mm. Try to slide it into the very slight gap between the rear surface of the bolt head and the front surface of the bolt carrier.
The .5mm measurement is the maximum the gap should be.
Open the feeler gauges to the .25mm leaf and try to fit that between the bolt head and carrier. The feeler gauge should fit without forcing it. Additionally, if the gap is smaller than .25mm the likelihood is that the gun will have problems with extraction / ejection. In fact, it may not run at all.

Buy the Right Gauges

You should buy a feeler gauge set that has several leaf sizes between .25mm and .5mm. This will let you get a good idea of the bolt gap. Checking this measurement regularly will let you track accurately the bolt group wear.

If the bolt gap is not between .25mm and .5mm, there are oversize and undersize rollers manufactured. Next, you can swap them with the stock rollers to either increase or decrease the bolt gap. Finally, if the gap is substantially out of spec, changing the barrel or reinstalling the barrel either further in or out may be required.

As a side note (I am not paid to say this)