Del-ton upper, and Stag lower?

[CMP_5.56]

So, I had a Very generous friend who gave me a stag lower. It was complete, but I changed the commercial buffer tube and stock, to a milspec one I had already. I picked you a bcg I had on holding at Bowers today, and with much disappointment, the rifle won't strip a round off of any magazine I have.

It seems like the bcg is getting caught up on the the feed lips of every mag I have.

Could it be that the upper and lower just don't like each other? I can't think of anything else it would be. I don't see how going to a milspec tube would cause this problem. Unless the buffer spring is somehow different than one for a milspec tube. But I thought outside dimensions were the only difference.

Either way, I'm one sad camper.

[ray1970]

Hmm. Out of curiosity, what kind of magazines are you using?

[CMP_5.56]

I ha e tried bushmaster usgi, c products usgi, colt usgi, pmags, and the same results with all of them. It's almost like the mags seat too far into the rifle.

[CMP_5.56]

When I charge the handle, and let it loose, the bolt makes contact with the round, starts to push it into the chamber, them stops. It seriously seems Luke the bcg is getting caught on the feed lips.

Also worth mentioning, I fired the upper on another forum members lower about 3 weeks ago. With absolutely no problems whatsoever.

[ray1970]

This one has me just a little stumped. I'd be happy to take a peek at it in person if you want. I've been putting these things together for about 20 years. Also, BPTactical is up in our neck of the woods and would probably take a peek at it for you if you wanted.

Shoot me a PM if you want me to peek at it.

[spleify]

Damn, I just want to know what you guys are doing up at 5am on Saturday...?

Cory, are you trying to load off of a full mag by any chance? I have one rifle that just will not pull the first round off of a full mag, be it a 20 rounder or a 30 rounder it will not draw that first round off of a full mag. That is one of the reasons I run all my mags 2 rounds short, then I dont have any issues

[Great-Kazoo]

Damn, I just want to know what you guys are doing up at 5am on Saturday...?

Cory, are you trying to load off of a full mag by any chance? I have one rifle that just will not pull the first round off of a full mag, be it a 20 rounder or a 30 rounder it will not draw that first round off of a full mag. That is one of the reasons I run all my mags 2 rounds short, then I dont have any issues

Up @ 5? I am up by 4 in the am then off to pt. If i log in b4 i take care of shit Nothing gets done on time:) Like i should be rolling out the door for the zombie shoot,.................

[CMP_5.56]

5am is almost the end of my day, habits from rolling around all night on the boo boo bus. Lol
I'm using 39 Rounders, loaded to 20 rounds, so not a full mag. I might have to have BP take a look at it.

[BPTactical]

Something is out of tolerance. My first thought would be an out of spec mag catch.
Try a different bcg.
Slide it by.

[CMP_5.56]

After heading to Bowers, to Hopefully buy a new magazine catch, the problem has been narrowed down to the feed ramps. It looks like dummy rounds loading fine, but when you out live ammo into it, the rounds are getting caught up on the feed ramps in my barrel. That happens with two different carriers, and two different lowers. So it looks like some dremel time is my near future.

[dwalker460]

I have seen non-M4 uppers with M4 barrels and vice versa have issues like your reporting.

[CMP_5.56]

I have seen non-M4 uppers with M4 barrels and vice versa have issues like your reporting.

The barrel has m4 ramps, and the upper has them too. There are a lot of sharp edges on the barrel extension. So polishing the Ramos my be a simple way to get the rifle running I don't think it's the end reality fix, but it may get it running.

[BPTactical]

Odd that it would strip and chamber a dummy and yet not a live round.
Don't over ramp it.
Still doesn't make a lot of sense that it ran before as you had mentioned.

[CMP_5.56]

I'm wondering if it is just stacking tolerances. Noveske bcg, stag lower, del-ton upper, and soon. I'm nit going to stone my ramps, just Polish with a teardrop polisher, staying with the ramp angle.

And I'm wondering if it ran before Because the tolerances were stacked the other direction. But I put my bcg in another upper, with my lower, no problems. My lower, and another bcg with another upper, no problems. Another bcg, another lower, and my upper, same problem. So I think the weakest link in my Frankenstein rifle, is my barrel. And possibly the barrel and upper. But I can't afford another barrel, or complete upper, so fixing what I have is about all I can do.

If I polish the ramps, and still have issues, then you'll get your hands on it Bert.

[BPTactical]

More than likely...

[CMP_5.56]

So, without actually firing my rifle, the polish job seems to have worked. I guess I will see after I put some rounds through her.