slow down rpm on m16 9mm conv unit?

dartswinger · 12-12-2011, 08:06 PM

I have an Olympic Arms/PAWS M16 and I have the complete 9mm conversion unit from Olympic with auto bolt and 12" bbl. that uses Sten mags. These mags seem fine is semi-auto but most are jam prone in full auto. I think the single feed mag. designed for a Sten with an RPM of what, 600 or so; just can't keep up with the unit I have which must be over 900 or so. I've fired Stens and they go pop-pop-pop my guy goes BBrrrrruuuupppp! It's an incredibly accurate and controllable little fella with the collapsing stock. I have 7 mags., one I shortened to just extend below the well but left the full spring in, its a **** to load but it always works, two others work also but the rest just can't seem to keep up as the bolt gets jammed in the rim recess. Is there a way to slow this rate to nearer 600 - or - are there new heavy duty springs that might make the mags. respond quicker. Two of my mags. would jam every 4th or 5th shot. I took the bottom off, stuck a chunk of wood up under the spring and reassembled, now they are 20 rounders but at at least they work flawlessly in semi and even make it thru full on relativily short bursts.

StoneChimney · 12-13-2011, 06:17 AM

You bet. Advanced Armament makes a cyclic rate reducer that will get you down to about 650 rpm, which is what you need to keep from overdriving your mags.

Available from Brownells or directly from AAC.

12-12-2011, 08:06 PM	#1
dartswinger V.I.P. Member Join Date: Jan 2010 Location: SE Pa. Posts: 146	slow down rpm on m16 9mm conv unit? I have an Olympic Arms/PAWS M16 and I have the complete 9mm conversion unit from Olympic with auto bolt and 12" bbl. that uses Sten mags. These mags seem fine is semi-auto but most are jam prone in full auto. I think the single feed mag. designed for a Sten with an RPM of what, 600 or so; just can't keep up with the unit I have which must be over 900 or so. I've fired Stens and they go pop-pop-pop my guy goes BBrrrrruuuupppp! It's an incredibly accurate and controllable little fella with the collapsing stock. I have 7 mags., one I shortened to just extend below the well but left the full spring in, its a **** to load but it always works, two others work also but the rest just can't seem to keep up as the bolt gets jammed in the rim recess. Is there a way to slow this rate to nearer 600 - or - are there new heavy duty springs that might make the mags. respond quicker. Two of my mags. would jam every 4th or 5th shot. I took the bottom off, stuck a chunk of wood up under the spring and reassembled, now they are 20 rounders but at at least they work flawlessly in semi and even make it thru full on relativily short bursts. -->

12-13-2011, 06:17 AM	#2
StoneChimney Advanced Senior Member Join Date: Nov 2010 Posts: 1,087	Re: slow down rpm on m16 9mm conv unit? You bet. Advanced Armament makes a cyclic rate reducer that will get you down to about 650 rpm, which is what you need to keep from overdriving your mags. Available from Brownells or directly from AAC. __________________ Full service gunsmithing and firearm manufacturing shop. Licensed FFL 07/02 Manufacturer. Visit our website!