My new M-4 clone

[RED]

Here is the brand new gift from my son. I have fired a bunch of AR's and M-16's in my life but this one is... well it is different. You can see one major difference right off. (Notice the forward assist.)

But that's not the reason for this post. What I don't know about this is:
1. How do you get the stock off the buffer tube?
2. Why are the gas rings one piece and not 3???
3. The extractor spring is different (it has an "o" ring).
4. Why does this rifle put a big dent in the fired cartridge cases?

Help this old fart get out of the 1960's, 70's?

[da gimp]

the one piece gas ring is a gimmick that is supposedly better than the old 3 piece...take the nut off the stock adj tab & stock should come off ok, dun lose de spring............. violent ejection for the dented cases, mebbe (guessing) either recoil (buffer) spring in stock is light/short, / or incorrect buffer, or too much gas being venred back.......What flavor is it Red?

[paul v]

To remove the stock...pull straight down on the adjustment lever (opposite the way you adjust the stock), while pulling down, slide the stock off the back of the tube. The first min and a half of the video shows this.
http://youtu.be/Z7ulYJN6OCo

[paul v]

The o ring on the extrator is to help eliminate failure to eject issues. It is probaly holding the spent case in the extractor causing the case to hit the receiver and denting it. You can remove it with no issues.

[PhillipM]

Here is the brand new gift from my son. I have fired a bunch of AR's and M-16's in my life but this one is... well it is different. You can see one major difference right off. (Notice the forward assist.)

But that's not the reason for this post. What I don't know about this is:
1. How do you get the stock off the buffer tube?
2. Why are the gas rings one piece and not 3???
3. The extractor spring is different (it has an "o" ring).
4. Why does this rifle put a big dent in the fired cartridge cases?

Help this old fart get out of the 1960's, 70's?

nice looking M4gery!

[RED]

Thanks again, you are all very helpful!

[RED]

Earlier I asked this question...

3. The extractor spring is different (it has an "o" ring).
4. Why does this rifle put a big dent in the fired cartridge cases?

...and got this answer...

paul v
The o ring on the extrator is to help eliminate failure to eject issues. It is probaly holding the spent case in the extractor causing the case to hit the receiver and denting it. You can remove it with no issues

.

I have an original GI extractor from the old days so I replaced the "improved" version with it. It made a big difference. The fired cases still have a very small dent but doesn't destroy them.

New question... I still have the upper receiver from my H&R M-16A1 registered machine gun. It will not mate up with my new AR lower but does mate up with my son's AR (same brand and bought at the same time). Any idea as to why?

Now to the dangerous waters... I have been told hundreds of times that you should never swap bolts. How true is that? How do you check the headspace and what gauges do you need.

I thought I knew a lot about this design and have fired 1,000's of rounds through M-16's. Once upon a time I put 5, 30 rd mags through a M-16A1 on full auto and the barrel glowed in the dark. It never missed a beat! The clones are different and apparently not as rubust as the older military spec stuff.

Thank you for any comments.

[Dienekes]

The O ring is there to prevent eventual failures to extract and double feeds. That tends to happen as carbines have an earlier and more violent extraction cycle. Apparently that's pretty common. In my case the O ring ended the problem right there. Some people also make sure they have a carbine-weight buffer in the gun as well, an "H" or "H2".

Headspace matters, although it doesn't seem to vary much. Swapping bolts is a poor idea although you might get away with it. Go and no go gauges to check, as per the manual. There's a learning curve, just like anything else.

[da gimp]

always use the correct buffer & spring for carbines..................never use a rifle buffer.............