SOCOMM magblock
Sten Mags
9mm Whitebox ammo 115gr almost exclusively

700rds not a single failure of any kind.  

I bought a NIB upper and my results have been great also.One of my mags has buggered lips and doesn't run well but I bought 10 of them for like $55 shipped.($55 for all 10,not each).I can likely save it with some dremel work but it is hardly worth the time.
I wacked about 3 or 4 turns off a couple of the mag springs to make them less of a job to reload.So far they work just fine, I think I will snip some more and see.At some point I will find how much is too much and have to throw out one but at $5 each- who cares. Stands to reason that a magazine used in a semi doesn't need to be as stiff as for a machine gun in military conditions.I use this upper for fun only,I wouldn't mess with the mags otherwise.I plan to get another couple dozen mags and that way I can load them at my leisure and not waste time trying to reload them at the range.

Hi Guys, so far I'm up to 7500-8000 rounds with my Oly and it's been very reliable.  Win White box, Wolf, Gold Dots and 9MM Nato. But it doesn't like Blazer...

I'm well over 10k on my oly - most of it FA, with the upper residing on a postie RR lower.  Gone through one extractor and one ejector in that time.  The extractor was an OOB accident caused by brass bouncing back in the port while using a brass catcher, with no other damage than the broken extractor.  The ejector went a few months ago, well after the 10k mark, was replaced from my spares on hand, and the rifle continues to run along just fine.

I used a modified (shortened) socom block with unmodified sten mags, and the upper's been chopped to 10" and mostly gets shot with an old rcgs 9mm can.  With 158gr subsonic it's unbelievably quiet, with standard 124gr NATO ball it's not really quiet, but not too loud, either.

I don't miss not having the bolt hold-open, I know it's out when it stops going ratatatat, same as my mac10 or mp5.

A note on mags - mags that have problems I mark and put aside, and most sten mags, from my beat up tapco $2 bargains to my occasional NIW's are fine.  I went way overboard back in the day and have a couple hundred sten mags to choose from.

Thats what Im talking about !!!!  Oly pistol cal uppers rock !!!  Thats why I use them on my rifles

~D~

SNS