Warning

 

Close
Confirm Action

Are you sure you wish to do this?

Cancel Confirm
AR15.COM
AR Sponsor
11/11/2008 6:09:12 AM EDT
I have built a total of 5 ARs including 2 M-4gerys and have not heard of them until my latest order to build #6.  What are the "feed ramp extensions" and what is their purpose?
11/11/2008 9:06:25 AM EDT
[#1]
Quoted:
I have built a total of 5 ARs including 2 M-4gerys and have not heard of them until my latest order to build #6.  What are the "feed ramp extensions" and what is their purpose?


Look it up on google for more info but in short I'll try:

At the end of your bbl is the bll extension. it looks like a 'Venturi Star', It mates up with the bolt every time a bullet is chambered or whatever. look inside your upper and notice the 2 ramps of the star that are shiny or worn out? Those are feed ramps. The ramps of your upper reciever and your bbl extension mate at this point. Your bullet tip skims along that ramp as it is on it's way to the chamber. M4 cut feed ramps are just wider/longer than the commercial/older feed ramps and they provide reliability under full auto fire and such. Basicaly you wont really notice unless you are shooting 'alot' and at once... (or specialty ammo) I prefer to have them just because it's an innovation that is proven to enhance performance and not hinder it in anyway; that I know of

GL, do some research... my explanation sux

Note: Your Upper Reciever and your bbl extension must both have M4 feed ramps to run together correctly. There is a thread on this already that covers it well so again, do your reseach;)


11/11/2008 10:18:43 AM EDT
[#2]
Quoted:


Note: Your Upper Reciever and your bbl extension must both have M4 feed ramps to run together correctly. There is a thread on this already that covers it well so again, do your reseach;)




You can run a rifle reciever with M4 barrel extension, but not the other way around.

11/11/2008 10:30:30 AM EDT
[#3]
Quoted:
Quoted:


Note: Your Upper Reciever and your bbl extension must both have M4 feed ramps to run together correctly. There is a thread on this already that covers it well so again, do your reseach;)




You can run a rifle reciever with M4 barrel extension, but not the other way around.



This is true. I have a non M4 extension bbl on an M4 extension Upper Reciever. Actually I have 2 that way ;)

11/11/2008 11:20:25 AM EDT
[#4]
Quoted:
Quoted:
Quoted:


Note: Your Upper Reciever and your bbl extension must both have M4 feed ramps to run together correctly. There is a thread on this already that covers it well so again, do your reseach;)




You can run a rifle reciever with M4 barrel extension, but not the other way around.


This is true. I have a non M4 extension bbl on an M4 extension Upper Reciever. Actually I have 2 that way ;)




What you listed is the complete opposite of what MW1831 listed in his post. You are saying you have a rifle barrel extension running on a M4 feed cut receiver, are you sure of that?



EDIT to add: Just to be clear if you look at the pic posted by TSLtrek in the bottom two pics what MW1831 described is the GOOD and what RALLYSOOB described is the BAD.
11/11/2008 11:28:32 AM EDT
[#5]
11/11/2008 11:33:25 AM EDT
[#6]
Quoted:
Quoted:
Quoted:
Quoted:


Note: Your Upper Reciever and your bbl extension must both have M4 feed ramps to run together correctly. There is a thread on this already that covers it well so again, do your reseach;)




You can run a rifle reciever with M4 barrel extension, but not the other way around.


This is true. I have a non M4 extension bbl on an M4 extension Upper Reciever. Actually I have 2 that way ;)




What you listed is the complete opposite of what MW1831 listed in his post. You are saying you have a rifle barrel extension running on a M4 feed cut receiver, are you sure of that?



read it again... you have it backwards in the way you are reading it ;)

or maybe the OP of the oprginial post is wrong... because in that post towards the end I come in stating the above as a Question and it indeed functions on my guns fine... Never had a JHP catch on me either and I'm using Barnes Varmit Grenades ever so often which to my knowledge have the biggest HP
11/11/2008 11:39:08 AM EDT
[#7]
What I read is that you have a non M4 extension barrel, so no M4 feed cuts in other words a rifle extension, mounted in a receiver with M4 feed cuts correct?
11/11/2008 12:01:38 PM EDT
[#8]
Quoted:
What I read is that you have a non M4 extension barrel, so no M4 feed cuts in other words a rifle extension, mounted in a receiver with M4 feed cuts correct?


yeah, i see what ur saying now... as stated above this issue has been addressed already. It would be more of a risk to try and have your rifle extension modified to become an M4 extension. So if your gun doesn't jam then there is no reason to fix it. But it should be known that either way you swing it the gun will work. Unless I just got lucky...twice...

AR Sponsor