Just cleaned my new rifle for 1st time.....

Can the bolt assembly be put into the bolt carrier 180 degrees the wrong way?  

I believe it can be, though I've never done it... Just make sure the ejector (metal flap with the spring) is on the right side of the rifle.

+1

if your staring at the face of the bolt (so that you can see inside the gas key) the extractor will be on the left. If worst comes to worst and you need a picture, check the top of the "build if yourself" section, or click here for instructions.

i don't think so because the cam pin will not get through the other side of the bolt, but still not sure..

Interesting. Now I'll have to try it.

nope, the cam pin will only go into the bolt from one side.

All 3 CMMG uppers I have will only allow it to enter one direction.





I test every new upper I get, so I know if I need to worry about it or not. I still pay attention, in any case.

I have a Stag.....they make lefties.....hmmm I need to check that again but I was pretty certain the key went in both ways!

Another interesting find...... in the USMC tech manual, they have a warning.....if you forget the bolt cam pin, the weapon will blow up on the first round!

That got my attention!!!!!

Correct me if Im wrong but if the bolt was to pick up a cartridge from the mag, it would not be able to go into battery because the cam pin isnt there to rotate the bolt forward? Not to mention the extreme chance it wont be able to align with the barrel extension due to the lack of a cam pin keeping it aligned. Also, because the bolt is not all the way forward, I take it the hammer wouldn't be able to strike the back of the firing pin.

I've had a bolt in a bushmaster upper that would insert both ways. Not sure what type of bolt it was.

There you go, fixed that for ya.
While this is true of most bolts, there seem to be manufacturers out there who do not feel that this is necessary.

I put the bolt from my bushy in backwards once, didn't realize it until I shot the gun and it jamned because the ejector pushed the round against the inside of the receiver. Man I felt stupid, and it was a pita to clear the jam.

Actually, the ejector is a spring loaded plunger in the face of the bolt. The "metal flap with the spring" is called an extractor. The ejector should be on the left and the extractor should be facing the ejection port side of the upper.

Remember, the bolt is extended out of the carrier when out of battery, as the carrier goes full forward and the bolt hits the barrel, the cam pin also reaches a channel that allows it to move.  The carrier continues to move forward and the bolt is stopped up against the barrel, the bolt pushes back into the carrier and the channel in the carrier rotates the cam pin and bolt as the bolt is pushed back into the carrier.

Thinking about it, I think it could be possible.  Yes, there is a chance the bolt would NOT be aligned and thus NOT go into battery, but if it was aligned, it would go into battery (or full forward, NOT sure if locked is part of being in battery) but NOT lock.  The bolt full forward, BUT NOT rotated to lock, would let the hammer hit the firing pin and fire the round with the bolt unlocked.  With bolt unlocked, as the round fired it would push back and open the breech, out of battery, then Kaboom!

Yes feeding a round would push the bolt back without the cam pin, but it would just push it back earlier than when carrier does when it goes full forward, when the carrier was full forward and the bolt lined up enough, the bolt would be home and the round would be chambered without the bolt rotated and locked.

Just pray, that if such a thing happens to you, that the bolt doesn't align to go into battery, or feeding the round pushes the bolt back farther than it would go with the cam pin, and thus not go into battery a let the hammer fall on the FP.

If you look close at the bolt, with the cam pin (but bolt out of the carrier) you'll see its only a very tiny lip of metal that makes one side of that cam pin hole in the bolt smaller than the end your suppose to insert the cam pin.  Its NOT hard to imagine that tiny lip sometimes gets missed in production.