AR-15 Rifle Test Quiz

[hoppy70]

AR-15 Rifle Test Quiz

I am semi-retired and I am taking a self-passed and self-taught Firearms Armorers course. I have covered over 25 different firearms in this course and now I am on the AR-15 Rifle course which is my last firearm in the Armorers course.

I hope to become a part-time light Gunsmith in the future. I am now working part-time with a Gunsmith that has over 40 year’s experience. I have my CHL and my FFL.

There are many questions covering this firearm and I have answered them to the best of my ability but during my study and research I am having some problems with these quiz questions. Either I am not sure of the correct answer or I have conflicting answers. I need to get 85% of the questions correct.

Can you help me determine the correct answers for these quiz questions? Please correct my wrong answers!

Thanks for your help.

1. The AR -15 was designed by
a) Ronnie Barrett
b) Max Atchisson
c) Eugene Stoner
d) Mikhail Kalashnikov

2. The front sight is held on by
a) Loctite

b) two tapered pins
c) one large roll pin
d) a quick release clamp

3. How is the gas tube retained in the front sight?
a) By a small roll pin
b) Friction
c) The gas tube is not actually held in place, as it needs to be free floating
d) By Gunsmith glue

4. What gun part is attached to the top of the bolt and accepts the gas from the rear end of the gas tube?
a) The bolt carrier key
b) The bolt face
c) The snap ring
d) The gas elbow connector

5. What holds the firing pin in place inside of the bolt?
a) The tapered retaining roll pin
b) The firing pin retaining pin
c) The extractor's tail
d) The ejector's shoulder

6. The gas from the fired cartridge exits the barrel and
a) enters the front sight and then the gas tube.
b) enters the gas connector piston and then the front sight.
c) enters the front sight and then the bolt carrier
d) enters the gas tube and then the bolt carrier.

7. What causes the bolt to rotate in the bolt carrier?
a) The bottom of the carrier key cams the rear end of the bolt and rotates it.
b) The expanding gas on the bolt face that comes directly from the gas chamber.
c) The cam-pin hitting the bolt carrier
d) The counter rotation of the barrel extension lug

8. What prevents the cam-pin from rotating in the bolt carrier?
a) The extractor
b) The firing pin
c) The bolt
d) None of the above

9. What pushes the hammer rearward after the gun is fired?
a) The rearward motion of the bolt, bolt carrier and the firing pin
b) The downward motion of the bolt carrier key as it hits the hammer strut
c) The rotation of the bolt
d) Both b and c

10. The secondary sear system's engagement is the contact between the hammer and
a) the disconnector
b) the receiver nut roll pin
c) the trigger
d) the rear of the bolt

11. The engagement of the hammer and the trigger best describes
a) the primary sear system
b) the secondary sear system
c) none of the above

12. The disconnector is also the secondary sear - True or False?

13. In the following scenario, the gun has been fired, the bolt has returned forward into its locked up position and the trigger is still pulled, which sear system is holding the hammer rearward?
a) The primary sear system
b) The secondary sear system

14. If the gun is at rest with the finger off of the trigger, the hammer is cocked and there is a round in the chamber, which sear system is holding the hammer rearward?
a) The primary sear system
b) The secondary sear system

15. The rear lips of the magazine box are what activates the bolt stop on the last round in the magazine - True or False?

16. The bolt catch will hold the bolt carrier assembly rearward after the last shot has been fired - True or False?

17. With the magazine out of the receiver, the bolt will still be held rearward after a shot has been fired - True or False?

18. What controls the cyclic rate of the AR-15/MI6 in full auto?
a) The diameter of the gas tube
b) The friction piece
c) The friction ring
d) The buffer assembly and the action spring

 

[Risky]

17 should be false. The magazine follower engages the bolt catch after the last round has been fired. If there is no magazine, the bolt will not automatically lock to the rear unless the bolt catch is manually depressed (like during an inspection arms in close order drill).

 

[taliv]

you missed 17

 

[Tommygunn]

I interpreted #17 to mean that if the gun goes empty, the magazine will hold the bolt back and once the magazine is removed, the bolt will remain back.
But I guess that's just how I read it....
Obviously if there's no magazine the gun will just cycle fully if the charging handle is activated.

This is a tad different than on, say, my M-1 Carbine where when I use 30 rnd mags the follower actually keeps the bolt back on empty and if the magazine is removed, the bolt will snap into battery since there is no internal mechanism on the M-1 carbine to hold the bolt back.

 

[jim243]

The way question 17 is worded is not clear. Yes the bolt will be held open when the mag is removed, but the bolt release is snaped in place by the tab on the mag follower. I think that the operative word in that sentence is "still", so the answer would be "TRUE".

Just my read on it.
Jim

 

[holdencm9]

If the bolt is locked back, and magazine is removed, it won't automatically send the bolt forward (that would be a dumb feature). I don't think the question can be interpreted that way because no modern gun I've ever heard of automatically goes into battery by removing the magazine.

If there is no magazine in the receiver, there is no "last shot" because you will be firing single shot. However the question is phrased "A shot"

So if you load one round into a mag, chamber it, remove the mag, and fire, the bolt won't lock back, so the answer to #17 the way I interpret it, is False.

Fun little quiz!

 

[Tex4426]

17 is correct...when u remove the mag the bolt stays open if it didnt what would be the point of the bolt catch release button or a B.A.D lever

 

[taliv]

read the question with the events occurring in the order listed.

mag out, then shot fired. you guys are making this too complicated

 

[holdencm9]

It is just worded weirdly.

With the magazine out of the receiver, the bolt will still be held rearward after a shot has been fired - True or False

After the last shot has been fired, the bolt will still be held rearward after the magazine is removed - True or False

 

[Tex4426]

It says after a shot has been fired...not after a shot is fired..which leads me to believe that it was fired before the mag release

 

[drsfmd]

read the question with the events occurring in the order listed.

mag out, then shot fired. you guys are making this too complicated

This.

It's a very poorly worded question, but Taliv's got it right.

For the OP, I would suggest you write up a narrative explaining the series of events. If nothing else, it will point out that they have a poorly worded question without needing to say so directly.

 

[DoubleTapDrew]

If the bolt is locked back, and magazine is removed, it won't automatically send the bolt forward (that would be a dumb feature). I don't think the question can be interpreted that way because no modern gun I've ever heard of automatically goes into battery by removing the magazine.

AK rifles with Yugo BHO followers in the mags will when the magazine is empty. A feature I don't like.

 

[shotgunjoel]

On #18, wouldn't the diameter of the gas tube affect the cyclic rate of fire? Wouldn't an overgassed rifle operate faster? While I agree with your answer, I think that A would also be correct.

 

[taliv]

yes joel, but since varying the size of the tube isn't a typical means of affecting the cyclic rate, it's not the "best" answer. i mean, i don't think you can buy different diameter tubes. (you can buy different lengths though)

 

[Walkalong]

17. With the magazine out of the receiver, the bolt will still be held rearward after a shot has been fired - True or False?

False of course.

The wording is quite clear to me. With the mag out, the bolt will not be held back if fired. This does assume a round in the chamber, but is that so hard to imagine.

 

[Quentin]

I see you finally got #7 corrected Hoppy!

 

[meanmrmustard]

If there is no mag in the receiver to actuate LRHO, it won't stay open on its own.

 

[justice06rr]

Why don't we put #17 to the test?

You guys are really making it too complicated. The answer should remain True.

With a mag or not, if you fire the last round the bolt should hold open correct?

 

[Walkalong]

If there is no mag in the receiver to actuate LRHO, it won't stay open on its own.

Correct.

With a mag or not, if you fire the last round the bolt should hold open correct?

Incorrect.

 

[taliv]

justice, you don't even have to fire a round to understand. just pop the upper off the lower receiver and watch the bolt catch as you insert a mag.

 

[steveo452]

#8 should be D, the hole in the cam pin is a clearance hole for the fireing pin. what prevents the pin from rotating is the head of the pin rideing in the rec.

 

[jim243]

#8 should be D,

It should be "C", the bolt. The cam pin rides in the bolt and is locked up when the rifle is in full battery. The hole is in the carrier.

As the gas pushes the "Bolt Carrier Group" rearward the cam pin will rotate the bolt clockwise and unlock the bolt so that the extractor and the ejector (also in the bolt) can eject the round.

Jim

 

[madcratebuilder]

Why don't we put #17 to the test?

You guys are really making it too complicated. The answer should remain True.

With a mag or not, if you fire the last round the bolt should hold open correct?

No. With the magazine removed, then fire the rifle, the bolt well not lock open. Locking the bolt back is a function of the magazine or engaging the bolt stop manually.

On #18, wouldn't the diameter of the gas tube affect the cyclic rate of fire? Wouldn't an overgassed rifle operate faster? While I agree with your answer, I think that A would also be correct.

There have been products on the market that offer a longer gas tube, the "pig tail" comes to mind. They don't do anything. They do not add sufficient volume or length to the gas tube to effect cyclic rate. There's just not enough room under the hand guards to do much.

Quote:
#8 should be D,
It should be "C", the bolt. The cam pin rides in the bolt and is locked up when the rifle is in full battery. The hole is in the carrier.

As the gas pushes the "Bolt Carrier Group" rearward the cam pin will rotate the bolt clockwise and unlock the bolt so that the extractor and the ejector (also in the bolt) can eject the round.

The question "What prevents the cam-pin from rotating in the bolt carrier" Answer, The firing pin.

Have you ever inadvertently assembled a BCG without the firing pin and then installed it? It locks the gun.

 

[jim243]

8. What prevents the cam-pin from rotating in the bolt carrier?

I guess it would be D) none of the above. Since it is held in by the "Cam Retaining Pin" not the firing pin or the firing pin retaining pin.

Jim

 

[meanmrmustard]

I guess it would be non of the above. Since it is held in by the "Cam Retaining Pin".

Jim

I'll bet you're right.