Home CMMG Sons of Liberty Gun Works East India Upper Receiver – Owner Induced...

Sons of Liberty Gun Works East India Upper Receiver – Owner Induced Feeding Problem

By
School of the American Rifle
-
1045
38

Sons of Liberty Gun Works East India Upper Receiver – Owner Induced Feeding Problem with Live Fire Testing.

EDITED TO ADD FOLLOW UP RESPONSE FROM THE OWNER:
Alright gents,

To ease any qualms, the issue was user error installing the rail. The reaction rod I used wasn’t stellar and is getting trashed.

The reaction rod used is called the “Real Avid lug lock”. It was recommended to me by a friend, but it didn’t perform as it should.

Note to readers: Please click the share buttons above or below. Forward this article to your email lists. Crosspost on your blog site, social media, internet forums. etc.

RELATED ARTICLESMORE FROM AUTHOR

38 COMMENTS

  6. I had issues until I polished my ramps as well. When I first started I felt like I had probably removed too much material. The finished product looked just like yours and the rifle functions flawlessly now so I guess it was just right.

  10. any owners of .22LR semi automatics like the Walther P22 for example, often have feeding problems because of the combination of the feed ramps are not smooth enough and various strength of 22lr ammo. I've personally owned my two P22's for 12 years and both had feeding and jamming problems because of the ramps being unfinished. Polished them out and they run incredibly consistent. Ive also repaired several customer weapons with feed ramps that suffered from overspray, corrosive pitting and sometimes just flat out unfinished feed ramps. Its not a cure all solution obviously but ive seen it fairly often in the last few years.

  19. Great video on feed ramp work. I've def dealt with this same issue before. Would of loved to see better lighting throughout the video while shooting close-ups of the feed ramps and the close-up of when it jammed. Just saying

  24. Nice work but I am curious why you would perform that work while in the upper receiver ? The reason I ask that is because now that you have obviously reshaped the feed ramps in the barrel extension the M4 feed ramps in the receiver are significantly smaller and out of proportion with those main feed ramps. Of course it is not that big of a deal since very little of the ( .223/5.56 ) cartridge will come into contact with the receiver ramps and as long as there is no positive elevation change or "lip" for the cartridge to get caught on it won't make that big of a difference. But if you performed this with the barrel in the receiver you could have easily & perfectly married & polished both sets of ramps at the same time.
    Again .. this method is not that big of a deal with the slender (.223/5.56 ) cartridge but becomes incredibly important with larger sized cartridges like the ( 7.62 x 39 ) for example.
    That only thing you really need to pay attention to is the fact that you are grinding & polishing 2 different materials ( Steel & aluminum ). Each with dramatically different properties. So I advise anyone that tries this to start by grinding the steel feed ramps in the barrel extension first and then once you achieve the desired shape then slowly move your grinding focus down into the aluminum. Pausing & checking to make sure the 2 surfaces meet. In fact, I will try to leave the level of the aluminum feed ramp in the receiver slightly higher than that of the steel feed ramp in the extension. Just in case the aluminum wears a little bit over time that the level won't fall below the steel ramp and cause a lip to form that could catch the edge of the cartridge.
    The ( 7.62 x 39 ) cartridge loads at a much flatter trajectory so widening the lowering the feed ramps makes a Massive difference with the much wider ( 7.62 x 39 ) and the only way I have found to match the angles & dimensions perfectly is if they are assembled.
    But I do this with my .223/5.56 uppers as well simply because it makes everything cycle that much smoother overall especially when you take into account the varying feed angles that are presented from some magazine manufacturers. Many drum magazines due to the unique spring systems & short lips present the cartridge into the receiver at a much shallower angle requiring the bullet to ride up the ramp which increases drag and can cause enough of a delay in the chambering process to cause the cartridge to hang up or a failure to feed.
    I'm just hoping to help. Especially when it comes to the ( 7.62 x 39 ) AK cartridge in the AR-15. It is an incredibly fun, inexpensive & effective round but SO many people give up on it due to its unreliability which much of it can be remedied through the reshaping & polishing of the feed ramps.

  26. You do spectacular work! Also just another reason you should clean your rifle after every time you take it shooting. He’s have been able to see that gouge with a flashlight if it wasn’t coated in filth. Clean your guns people. Especially if you are having problems.

  29. I had this problem as well when my colt was brand new. But I fixed it myself, I did not have to take the barrel off tho. I used a small file and a polishing wheel. Although mine didn't hang up as much as his, my bullets were just getting scratched up.

Leave a Reply