shooterrex Posted January 19, 2019 Report Share Posted January 19, 2019 I bought a Stoner 9mm upper from Midway. Supposed to work with Glock and Colt mags. I installed a Yankee hill 9mm buffer 5.9oz. I have the Stern defense mag block to use Glock mags. If I lower the adapter block down past the regular mag catch it will load,fire, and eject about 80% of the time. The rest of the time the bolt doesn't go all the way into battery. I have also tried the endomag adapters that go in a pmag. Same results.This started on a collapsible stocked lower. I have also tried it on a A2 lower my Beowulf upper is on. Same results doesn't go into battery about 20%of the time. Any ideas what to try next? Maybe a 308 buffer spring ? Kinda running out of ideas. Quote Link to comment Share on other sites More sharing options...
98Z5V Posted January 19, 2019 Report Share Posted January 19, 2019 6 minutes ago, shooterrex said: I bought a Stoner 9mm upper from Midway. Supposed to work with Glock and Colt mags. WHOA! Those are usually two completely different platforms and lowers, right there. Glock mags are, well, Glock mags. Colt mags are almost identical to the 32-round UZI mags. It's not the upper that's probably giving you the issues - it's whatever is going on with your lower setup. Pics, please. Quote Link to comment Share on other sites More sharing options...
shooterrex Posted January 19, 2019 Author Report Share Posted January 19, 2019 The bolt is supposed to be relieved to work with either mag set up. At least that is what Midway's web site says. If I can't figure this out I'll just buy a PSA lower for glock mags. Quote Link to comment Share on other sites More sharing options...
shooterrex Posted January 19, 2019 Author Report Share Posted January 19, 2019 I sold my Spikes 9mm pistol to a friend a while back. It used the Colt mags and ran ok. He offered me way more money than I had in it. The endomag just replaces the follower and spring inside a pmag. Neat setup if I can get it to work Quote Link to comment Share on other sites More sharing options...
308kiwi Posted January 19, 2019 Report Share Posted January 19, 2019 (edited) Like 98 says, two different systems. The Glock mag feeds from the centre of the mag, the Colt/Uzi mags feed left and right alternatively, so the bolts are different, ie they have a different width relief machined on the bottom of the bolt to clear the feed lips, depending on what mag system they are designed for. I know you say your bolt is supposed to be 'both', but it sure as fuk sounds like this is your problem, the mag feed lips are contacting the bolt as it goes into battery, this also explains why you are having 'some' success when you lower the adapter block, effectively lowering the mag feed lips in relation to the bolt. I've modified quite a few of these bolts so that they work with Glock mags, only way I've found to sort this issue. Edited January 19, 2019 by 308kiwi Quote Link to comment Share on other sites More sharing options...
Armed Eye Doc Posted January 19, 2019 Report Share Posted January 19, 2019 It looks like this may be the upper. https://www.midwayusa.com/product/1019229168/ar-stoner-ar-15-optics-ready-upper-receiver-assembly-9mm-luger-16-barrel It does say it should work with both types of mags. Quote Link to comment Share on other sites More sharing options...
shooterrex Posted January 19, 2019 Author Report Share Posted January 19, 2019 32 minutes ago, Armed Eye Doc said: It looks like this may be the upper. https://www.midwayusa.com/product/1019229168/ar-stoner-ar-15-optics-ready-upper-receiver-assembly-9mm-luger-16-barrel It does say it should work with both types of mags. Yep that is the upper. It was $219.00 shipped on sale with a coupon. Quote Link to comment Share on other sites More sharing options...
shooterrex Posted January 19, 2019 Author Report Share Posted January 19, 2019 49 minutes ago, 308kiwi said: Like 98 says, two different systems. The Glock mag feeds from the centre of the mag, the Colt/Uzi mags feed left and right alternatively, so the bolts are different, ie they have a different width relief machined on the bottom of the bolt to clear the feed lips, depending on what mag system they are designed for. I know you say your bolt is supposed to be 'both', but it sure as fuk sounds like this is your problem, the mag feed lips are contacting the bolt as it goes into battery, this also explains why you are having 'some' success when you lower the adapter block, effectively lowering the mag feed lips in relation to the bolt. I've modified quite a few of these bolts so that they work with Glock mags, only way I've found to sort this issue. Thanks for the info. I might have to do some trimming. Quote Link to comment Share on other sites More sharing options...
shooterrex Posted February 12, 2019 Author Report Share Posted February 12, 2019 The bolt will not even clear a pmag with no follower or spring. Even with 5oz buffer and 308 carbine spring it will run sometime with the mag block lowered. Fired out of battery. Grendel barrel and bcg are on the way. No wonder midway had these uppers on closeout for $219. Seemed like a fun idea but I'm tired of screwing with this. Quote Link to comment Share on other sites More sharing options...
jtallen83 Posted February 12, 2019 Report Share Posted February 12, 2019 2 minutes ago, shooterrex said: Fired out of battery. YIKES! Quote Link to comment Share on other sites More sharing options...
98Z5V Posted February 13, 2019 Report Share Posted February 13, 2019 6 hours ago, shooterrex said: The bolt will not even clear a pmag with no follower or spring. Even with 5oz buffer and 308 carbine spring it will run sometime with the mag block lowered. Fired out of battery. Grendel barrel and bcg are on the way. No wonder midway had these uppers on closeout for $219. Seemed like a fun idea but I'm tired of screwing with this. I've played with mine enough with the 3.250" buffers, even H3 buffers at 5.4oz - I went to the 8oz 9mm-specific buffer. Threw one in the .45AR, too. Blowback pistol cartridges are a bitch to tame in the AR platform. Quote Link to comment Share on other sites More sharing options...
shooterrex Posted February 13, 2019 Author Report Share Posted February 13, 2019 I'll keep the parts and try to get this to run some other time. The grendel sounds like more fun at the moment. Quote Link to comment Share on other sites More sharing options...
98Z5V Posted February 13, 2019 Report Share Posted February 13, 2019 28 minutes ago, shooterrex said: I'll keep the parts and try to get this to run some other time. The grendel sounds like more fun at the moment. Oh, it is... Get with me on your plan -post it up. I'm on #5 now. I can give you loads, drops at distance, whatever. It's a magical cartridge. Quote Link to comment Share on other sites More sharing options...
Matt.Cross Posted February 13, 2019 Report Share Posted February 13, 2019 1 hour ago, 98Z5V said: Oh, it is... Get with me on your plan -post it up. I'm on #5 now. I can give you loads, drops at distance, whatever. It's a magical cartridge. Yes, yes it is! A spectacular little performer of a cartridge.... Just amazing! Quote Link to comment Share on other sites More sharing options...
shooterrex Posted February 13, 2019 Author Report Share Posted February 13, 2019 (edited) 3 hours ago, 98Z5V said: Oh, it is... Get with me on your plan -post it up. I'm on #5 now. I can give you loads, drops at distance, whatever. It's a magical cartridge. BCS 16" fluted barrel and BCG. Low profile gas block (that was on the 9mm upper). 15" M lock rail. The 9mm upper doesnt have a forward assist but i can live without that I think. Have 500 rnds of wolf fmj and 100 rounds of hornady black on the way . ACS Mags also on the way. Haven't bought dies yet. Havent figured out glass yet. I have some scopes sitting around here somewhere. But nothing for long range. Edited February 13, 2019 by shooterrex fat fingers Quote Link to comment Share on other sites More sharing options...
shooterrex Posted February 13, 2019 Author Report Share Posted February 13, 2019 The new barrel is nitride 1 in 8 Quote Link to comment Share on other sites More sharing options...
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