I just bought my first AR-15 () which is a Rock River Arms M4gery with the 16" barrel and heard that I can just remove the upper and put on any post-ban upper (like a 20") and have it work right away - like a 5 second swap.  My question is, I have seen the AR-15 7.62x39 uppers - can I swap these in the same manner?  If so, what do I need to make sure they have (I assume a bolt/etc. made for the 7.62x39 round)?  I also assume they take different mags.  Are the mags hard to find?  Do they require any special adapters for the magwell, or are they the same size as normal AR-15 mags?

Thanks!

Model 1 Sales has 7.62x39 uppers in stock and ready to ship.  They are selling them (complete with bolt/carrier) for about what the dealer cost is from OLY or RRA.  I ordered a flat top 16" and had it in my hands in 3 days.  Great service and product.

There are no adapters or mods needed to pin on a 762 upper to a standard lower.  As for the mags, you can use standard AR mags with no problem.  Because of the dimensions of the 762 round, you can only load 7-9 rounds.  There are some "Franken Mags" out there if you can find them.  This is an AK mag with an AR mag upper 1/3 welded on.  Very strange looking and I have never tried them.  The last alternative is to get one of the new SW lowers that accept unmodified AK mags and drums.  I just finished mine and it runs great.  Here is a pic.........

[img]http://www.crinamex.com/ar47drum.jpg[/img]
[img]http://www.crinamex.com/ar47waffle.jpg[/img]

I have a 7.62x39 Colt or 2.

USA frankenmags feed flawlessly, no matter the capacity.  Had to comform a couple of the mags to fit the magwells...  Bend, twist, squash..

The 7.62 USA frankenmags work in [red]all[/red] my lowers.

I have a couple of other frankenmags that do not like bump firing.  Maybe I just fuxxored them up with my hammer.  WECSOG!!!!

YMMV

ONE QUESTION:  WHY???

You can get a REAL AK for $330.00 that works flawlessly.

I guess this means you shoot a $500 OLY plinker?  No sense wasting all that hard earned cash on one of those overpriced Bushmasters.

I built my AR47 for only one reason, I wanted to.  I thought it would be a nice addition to my 223's and 9mm and I did not want to go the "only load 7 round" or "Frankenmag" route.