TGibe Posted December 16, 2017 Share Posted December 16, 2017 15 hours ago, bmiller said: On the NFA lower, over insertion is stopped by the ejector, it acts as a stop for the mag. You have to remove the ejector from the lower to run the guard bolt because it is not slotted. I have been machining stops that drop in place of the ejector of the NFA lower. My NFA lower works great the the guard upper with the stop installed. Maybe my Spartan lower is not an NFA then because while the ejector will eventually stop the mag it is high enough where I can go past the mag release a good distance if I hold the mag release down. No biggie either way was just trying to clarify the CMMG lower mag stop... thx, Allen Link to comment
TGibe Posted December 16, 2017 Share Posted December 16, 2017 1 hour ago, TGibe said: Maybe my Spartan lower is not an NFA then because while the ejector will eventually stop the mag it is high enough where I can go past the mag release a good distance if I hold the mag release down. No biggie either way was just trying to clarify the CMMG lower mag stop... thx, Allen Ok. Once again I’m wrong... the ejector does stop the mag from over insertion on my NFA. Sorry for the confusion, but sometimes I can be dense... Link to comment
NickBlasta Posted December 20, 2017 Share Posted December 20, 2017 Picked up one yesterday, looking forward to doing some science. Link to comment
amish_rabbi Posted December 23, 2017 Share Posted December 23, 2017 where are you guys finding the uppers? I can't seem to find them on the cmmg site Link to comment
bmiller Posted December 23, 2017 Share Posted December 23, 2017 1 hour ago, amish_rabbi said: where are you guys finding the uppers? I can't seem to find them on the cmmg site Building them. They sell a barrel and bolt combo. Link to comment
TGibe Posted December 24, 2017 Share Posted December 24, 2017 2 hours ago, amish_rabbi said: where are you guys finding the uppers? I can't seem to find them on the cmmg site https://www.cmmginc.com/product-category/uppers/9mm-guard/ This is where I ordered mine. Link to comment
amish_rabbi Posted December 25, 2017 Share Posted December 25, 2017 On 12/23/2017 at 7:01 PM, TGibe said: https://www.cmmginc.com/product-category/uppers/9mm-guard/ This is where I ordered mine. thanks! somehow the website options couldnt find it for me Link to comment
bmiller Posted December 25, 2017 Share Posted December 25, 2017 A friend and I tested a few guns yesterday. We shot some slo-mo video of him shooting my pcc with the guard system installed. Those loads are 144 power factor. 124 grain bullets. In the next couple weeks that upper is going to get chopped, popple holes drilled, and a bloop tube pinned and welded. The lower is my billet PSA with my magstop installed. So far, it has ran flawless. Link to comment
NickBlasta Posted December 31, 2017 Share Posted December 31, 2017 Finally managed to get some time off work so I had both guns down at the range today. Thoughts- The delayed blowback is very soft. The cycling is still chunkier than a 5.56 AR but much less than a blowback. In particular I noticed the lack of the smack at the end of the cycle when the blowback bolt closes. It seems to like different loads than the blowback gun. I've been using a heavy bullet in the blowback gun (a 165gr load) but it felt like it took forever to cycle the guard. My doubletapz were closer together with a snappier load. Anyway, a little video Link to comment
gsmithl10 Posted January 1, 2018 Share Posted January 1, 2018 Hey guys, I have a PSA lower and im looking ar the Guard upper. Couple questions 1.) Are there any limitations on after market triggers 2.) @bmiller how do I get one of the mag over travel stop 3.) Is there anything I'm missing, to make the gun run? Link to comment
bmiller Posted January 1, 2018 Share Posted January 1, 2018 1. All I run is hiperfire in everything. I know it works fine with mine. 2. dandbmiller@hotmail.com 3. I put the over travel stop in, and had to slightly file some mags for clearance for the bottom lug. That’s all I did with mine. It is the softest shooting setup I have fired. Link to comment
NickBlasta Posted January 2, 2018 Share Posted January 2, 2018 Shot it today at a small match, little new years fun shoot. I'm pretty surprised by the lack of recoil almost every shot. Link to comment
solaritx Posted January 4, 2018 Share Posted January 4, 2018 Interested in the .45 version. Anyone have any info. Everyone seems to have issues with .45 PCC...... wondering if the Guardian is reliable and how it runs Link to comment
BartCarter Posted January 8, 2018 Share Posted January 8, 2018 First actual comparison that I have seen between MP5, MPX, Scorpion, and CMMG Guard. MP5, MPX, Scorpion, and CMMG Guard comparison Link to comment
bmiller Posted January 8, 2018 Share Posted January 8, 2018 I shot an indoor match yesterday, after the match we shot my two pccs next to a mpx all with my ammo. My blowback gun was the lightest weight by far, and the sharpest recoiling. I just have a ninjaflex spacer in the buffer tube. I am running a PSA 9mm buffer and spring. I am not running any type of pogo stick contraption in it. I might try one in the future. The mpx was a stock carbine, I am not sure what it weighs. My rifle with the guard upper weighs about 7.5 pounds. A bunch of guys shot them. The overall opinion was the sig was the softest, but not by very much. The guard was a close second. They thought my blowback gun recoiled just slightly less than an elephant rifle after shooting the other two. Most shooters thought the sig had a chubby, bloated feel, but they thought it was very smooth. The ammo was 124 grain 144 pf out of a 16” barrel. The same load was used in all rifles. I am not sure how they did it, but two shooters managed to get my guard to jam. Something I had not had happen to me. Both shooter said they were holding it loosely. Both are pretty strong guys, and the one guy, if he wrestled a grizzly, I am not sure who I would bet on. Not sure what was going on there. Link to comment
Garmil Posted January 9, 2018 Share Posted January 9, 2018 On 1/4/2018 at 12:09 PM, solaritx said: Interested in the .45 version. Anyone have any info. Everyone seems to have issues with .45 PCC...... wondering if the Guardian is reliable and how it runs If you haven’t seen yet lone wolf has a new piston .45 pcc might be worth looking at as well. https://www.lonewolfdist.com/awpcc.aspx Link to comment
Marshal82 Posted January 10, 2018 Share Posted January 10, 2018 (edited) There are some limitations as you guys are seeing. The Guard lower puts the mag about 0.100-0.125in lower, it also has a slightly different angle. Barrel is a normal M4 extension but with center receiving lug ground down. Bolt is a custom with the same lug pattern, bottom 2 lugs cut down to clear feed lips. @bmiller has done what I thought of, to machine and install a Mag travel stop in the NFA lowers however for proper mag placement you have to lower the mags. I would file off the mag catch not the actual mags. I have the Guard lower and doing some testing of my own, the system is a step in the right direction but not quite there yet. Edited January 10, 2018 by Marshal82 Link to comment
bmiller Posted January 10, 2018 Share Posted January 10, 2018 I did not need to alter the mags other than some Glock mags need opened at the top a small amount. Mine does not like ets mags, they are too narrow between the feed lips. I keep thinking about a piston drive system for system. I like the mpx, not sure it is for me. Link to comment
solaritx Posted January 17, 2018 Share Posted January 17, 2018 On 1/8/2018 at 6:11 PM, Garmil said: If you haven’t seen yet lone wolf has a new piston .45 pcc might be worth looking at as well. https://www.lonewolfdist.com/awpcc.aspx Thank you.... will look into it. Link to comment
BartCarter Posted January 18, 2018 Share Posted January 18, 2018 On 11/20/2017 at 4:29 PM, mahamoti said: ... CMMG says uppers "may require modification." ... Revisiting this, I feel that an AR15 upper needs modification. I took my new build from the CMMG Guard BCG/barrel/lower for sighting in and testing of magazines, etc. I was getting about 1 in 15 failing to eject. On another forum that has a long Guard thread, CMMG said if you don’t use their upper, you may have to clearance the ejection port. I didn’t think much of this as Colt SMG uses a standard ejection port that works well with 9 mm. Now I feel differently. In comparing the factory Guard and my AR15 upper, there is quite a difference between the Guard ejection port and an AR 15 ejection port. The guard ejection port is clearanced on the lower edge all the way to the bolt bearing surface. The top edge is clearanced on the first half of the port to the extent it takes out about half of the upper bolt bearing surface. The ends of the Guard port are also more squared off instead of round, probably due to the end mill size. I feel CMMG did this for reliability and maybe to accommodate different types of ammo. Also, who knows the differences in the shell ejection between a Colt SMG style ejector and an AR15 type of ejector. I had my mill set up for milling lines in my last linear comp. Should not be hard to do an exact reproduction of the Guard upper. If this stops the ejection problem, it would make sense to use the Guard upper with the BCG/barrel/lower for a custom build. (If you don’t have a mill with a rotary table. ) Link to comment
TGibe Posted January 19, 2018 Share Posted January 19, 2018 (edited) On 1/17/2018 at 4:47 PM, BartCarter said: On another forum that has a long Guard thread, CMMG said if you don’t use their upper, you may have to clearance the ejection port. Thread is at https://www.ar15.com/forums/AR-15/Thoughts-on-the-CMMG-Guard-/15-713060/?page=8 Edited January 19, 2018 by TGibe Found thread using search... LOL Link to comment
bmiller Posted January 19, 2018 Share Posted January 19, 2018 (edited) I found it on ar15.com Edited January 19, 2018 by bmiller Link to comment
BartCarter Posted January 29, 2018 Share Posted January 29, 2018 On 1/17/2018 at 4:47 PM, BartCarter said: Revisiting this, I feel that an AR15 upper needs modification. I took my new build from the CMMG Guard BCG/barrel/lower for sighting in and testing of magazines, etc. I was getting about 1 in 15 failing to eject. On another forum that has a long Guard thread, CMMG said if you don’t use their upper, you may have to clearance the ejection port. I didn’t think much of this as Colt SMG uses a standard ejection port that works well with 9 mm. Now I feel differently... Finished milling my upper to open up the ejection port. I milled the top front half 0.038" and the entire length of the bottom 0.110". I ran all my Glock mags from fully loaded and not one failure to eject. Today I ran a steel match and not one failure to eject. 400 rounds total. So, if you are having any ejection problems with your Guard barrel/BCG build, I highly recommend clearancing the ejection port. Link to comment
Marshal82 Posted January 29, 2018 Share Posted January 29, 2018 I've used uppers meant for 458 socom since they have the larger ejection window and no issues so far. Link to comment
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