If I use sten mags with a KKF mag well block is it just as reliable as the colt system and what upper do I use with the sten system?or can I just get a barrel assembly and use with any uper?

I'd rather think about how much ammo I will be using.  In my M16, I'd rather use UZI mags because of the speed loaders available.  FWIW

They Olympic upper is the one that is currently using Stens and a SOCOM block (or a spacer tube on the back of the Sten mag).

YOu can't just get a barrel assembly because of the ejector. Oly uses a spring finger to eject the spent case while in the Colt system, there is an ejector connected to the mag well that "flicks" out the case.  And the bolts are totally different also.

My Oly conversion was 100% reliable.  

Thanks for the help guys,looks like im gonna try the olympic one.

I would pick the COLT style one myself.

You can get a HYTECH block and use unmodified UZI mags. They are around $12 each.

Have JoeBlack ramp the bolt and you can use a 223 lower.

I went with a RRA flat top upper, ramped bolt, RRA lower, 9mm hammer(bought it before I ramped the bolt), 9mm mag catch(so colt mags will hold open), Garrison mag block, 9mm buffer(a MUST HAVE).

I forgot to address the reliability aspect of the question...

It all comes down to mags.  How they fit in the adapter (which ever adapter one uses), how they feed the rounds and at time, type of round.

It may sound odd, but taking X parts from 1 place and using them in gun A may work fine, but the same adapter, mag and upper might not in gun B.  Funny.  Or even just 1 mag that works fine in one set up might not in another.

I have a Colt style as I have posted.  I have many different types of mags for the set up.  Modified uzi, madsen, South african single feed type.  I've had my share of problems with them all...except the madsen mags...works great.  Any how, I have to ask, do you want 100% reliability out of the box/wrapper???  In my opinion, it's not possible with the 9mm set up, not with as many mags, blocks and upper and the variations (tolerances, so forth).  Some kind of tweeking, mods are required.  Some of my modifications would make people cringe (I've made USA uzi/ar mags work, but they look cheezey).  Some of my fixes people would laugh at, but it works.  It depends on you, as the owner, on how much you want to do, if things don't work out.  We only offer our opinion..... the choice is yours.

You asked about which used Sten mags.  At this point, w/out making a custom block (aka Sten block for Colt system use), the Oly system is the only one to use Stens (modified or unmodified).

Some out there will agree with parts of what I say, others will not.  I am fortunate to have a fairly working 9mm set up.  No problems any more.

Thanks all for the info and to KALIBURZ very informative.To DrugRunnr do you have any info where I can go on line to see the garrison mag block or HYTECH conversion..Thanks927

[url]http://www.ar15.com/forums/topic.html?b=3&f=15&t=173301[/url]

and look at the sticky at the top for the hytech block.