M4 Feed Ramps

AR/M4 AR General Discussion
1

I recently purchased a new complete upper and the M4 feed ramps on the upper receiver are a lot shorter/smaller than on my other uppers, as well as pretty much every picture I see posted of M4 feed ramps. What’re everyone’s thoughts on these feed ramps?

I suppose you could say small M4 feed ramps are better than none, but I would prefer to have them the proper length/size. Below is my new upper and one of my other uppers for comparison which has normal length M4 feed ramps (both are 16” mid-lengths).

New upper:

Other upper for comparison:

2

Hardly machined in the first pic but the barrel extension’s ramps appear to mate nicely, if it functions then don’t worry about it. What make is the upper? I don’t know if there is a standard length that the ramps have to be but it seems as though there would be and all the ones I’ve seen are similar with the exception of the one you have there.

3

Curious about manufacturer as well.

If I remember correctly M4 feed ramps are not necessary unless running full auto. LaRue Tacticaluppers do not use M4 feed ramps and had some pretty valid reason for not using them. wish I had a link to the article. RRA doesn’t use them either

I imagine the upper will run just fine.

4

I’m with jet - whiile tehy are admitedly a littel smaller than what I’d say I’ve normally seen, it may not really be a huge deal prvided it functions well, both clean and dirty.

5

My Noveske looks like the top picture (Noveske factory rifle with VIS upper). A much shallower cut than I was use to seeing compared to other M4 cuts. Everything works great though.

6

Last time I saw an RRA, they were dremeling them in after assembly. Have they stopped this practice now?

7

They’re not needed at all in my experience. Those look fine. My Colt Commando upper had worse looking “m4” feedramps than those.

8

I’d not worry about those. They don’t look normal, but they’re not going to cause a problem.

9

I’d also like to know who makes the ones on the pictures.

10

Thanks for the replies everyone. I’d rather not say the make of the upper without first hearing the manufacturer’s comments on it, whom I will contact right after this. The bottom picture with the normal M4 feed ramps is a BCM if anyone was wondering about that one.

I certainly hear what you folks are saying that M4 feed ramps aren’t “needed” and ARs ran well for quite a few years before M4 feed ramps existed. However, in its current state I’m kind of getting the worst of both worlds, the steeper incline of the M4 barrel extension with almost no extended ramps onto the upper. In all likelihood this will never cause me any problems, but I guess I’d feel more confident in it if it had the standard size M4 feed ramps in the upper.

11

I suppose you could say small M4 feed ramps are better than none,

No. In my experience the ramps need to work, and for that they need to be machined so there are no lips or other protrusions which would inhibit 100% feeding.

For instance the LaRue Stealth guns do not come with M4 ramps, and Ive yet to hear of anyone who has reported problems due to lack of M4 feed ramps, and I have over 10k rounds through two uppers without a single feed issue from FMJ steel case rounds to heavy match 5.56 loadings.