BartCarter

I use a Venom on both my PCC and pistol. Helps with consistency. I don't really take the housing size as a consideration, I just look for the dot. That works for me best after trying different sights. Different people use different ways to help with sight alignment. See if you can try some different setups to see what works best for you.

Well, ordered the Guard 9 mm today. I found the basic rifle for $1085 shipped at Four Winds Technology. I don't know how long it will take to get here. They said it was in stock, but were not firm on processing my order or shipping. Also ordered a POF (my favorite) 4.5 lb. trigger and Glock 33's and Magpul 21's. Will probably replace the stock, but keep the hand guard. Supposed to be 6.2 lbs. Full report as soon as it gets here. Crap, I thought I was through with my PCC when I did well in Sunday's IDPA match.

The CMMG Guard 45 cal Radial Delayed Blowback has been out about 5 months. The first day of endurance testing they shot 7500 rounds, cleaning it every 3000 rounds. Good reviews. The 45 runs a standard H buffer and recoil is less than that of a blowback 9mm. They have a weight tuning kit that changes the way the rifle shoots with +P and suppressors. When the 45 came out, I was building my 1st PCC. If it was 9mm, I would have bought it. Now 5 PCC builds later, I am thinking 9mm Guard. Looking at the difference between buying parts and adding my choice of stock, trigger, etc. and buy their lowest price complete and swapping parts. Looks like I should just by the complete. 1st dealer that has the normal dealer pricing will get my order. Just when I finally get my PCC where I want it ....

Where is the Colt magwell?

Yes, with the Blitz buffer. I have a 7.5 oz solid buffer and have just acquired a KAK 9mm adjustable weight buffer.

Thanks Eric. So between 18.3 and 19.2 total weight with 131-138 PF. As the PF goes higher (I don't load) and keeping a 223 carbine spring, would I add a little weight? I'm estimating my PF with Fiocchi 115 FMJ at 149. I am going to chronograph, hopefully, this week. Thanks, Bart

After becoming an "expert" at the differences in mags, I will only buy Colt mags now. The ASC mags are all "tuned" and work fine, but I shouldn't have to do that. Also you can see the quality difference in Colt versus ASC, such as metal thickness and cheap paint versus proper finish.

When talking about rifle versus carbine springs, is that .308 (heavy) versus 5.56 (standard)? I like the lighter (5.56) spring in my PCCs so far. Also, would there be a difference if a flat spring were used? I am having no trouble hitting where I want, but I would like to be able to do double taps like I see posted. Has anyone ever analysed or compared a heavier buffer that utilizes different weights with the rubber spacers? I understand that those work similar to a dead blow effect.

I have found these to be my choice also. I tried different generic double and single stack pistol mags, but these are much better. You can adjust them with their "springs" to be the best fit for your mags. I found price and shipping time to be good .

Well, my gap is good then. Maybe I need to think about not working the LRBHO and changing mags if I need to.

My bolts are all adjusted for limited travel. Does this eliminate concerns?

I have seen a recent post that the bolt hold open broke on the 2nd mag and advice not to use it. I run to slide lock all the time and have not had any problems. (CMMG and Spikes Tactical dedicated lowers) Looking for some feedback: Am I living or borrowed time? Is my "collection" of parts lucky? Are there others that don't have a problem? Should the bolt hold open be replaced as a preventive maintenance part? Thanks, Bart

I don't know much about MPXs, other than many of you have them. Just got a flyer that has Gen 1 Mags for $19.95 MPX Mag Sale

Put a bag holder on the cart instead of gun clamps?

Yes, similar. But my tip was not as degraded and the shoulder was not as worn - there was still most of the taper left. Looks like yours has the taper worn away (by striking the bolt?).

OK, haven't broken a firing pin yet, but I just closely inspected the firing pin in my CMMG bolt at about 3,000 rounds. The firing pin tip looks like it has been beaten up a bit. The shoulder at the end of the firing pin tip looks like it has been hitting on part of the inside of the bolt, causing a ridge to form. The back of the firing pin has a slight mushroom. I replaced with the spare I keep on hand. Maybe firing pins should be replaced as a normal maintenance. POF 4.5 lb trigger.

Well, moving the ejector closer to the bolt solved the ejection problem. It is amazing how little movement changed the 1 out of 3 failures to eject to now the 100% reliable ejection. I guess from now on I will adjust the ejector to as close as practical to the bolt before I even do my first test.

I, too, have gone to optics because of my vision. I first used a 3 MOA dot because that is what I had at the time. I have 6 MOA on my pistols. Now I can't see changing from the 3 MOA for my PCC. The last local IDPA match, I was 2nd overall out of 64 (only 3 PCC though) and had the least points down of anyone. I have no trouble seeing the 3 MOA dot and putting it where I want it. (Vortex Venom). I have shot with scopes, tube red dots, triangles, cross hairs, circles, etc. But it is just so easy to put that little dot on the target and press. Only thing you really need to think about is your offset.

Yes, checked that. I actually moved the ejector closer to the bolt because I was having brass not ejecting every third round or so. Haven't tested if that solved the ejecting problem, but I made sure that the ejector is not rubbing. So many things that can go wrong. In building other PCCs I had to resolve other issues. And it is not necessarily just from building one yourself using different parts from different manufacturers. One of my friends just had to send back his factory PCC from a well known and respected manufacturer. I'm sure they have seen everything and will "adjust" something to make it right, but goes to show you that tuning may be necessary, no matter what the source. It is nice to have a source such as this forum to help trouble shoot and modify PCCs for those of us that do it ourselves. Thanks again to forum members for the help.

Embarrassment continues: I wasn't using my Colt mags, I was using my ASC mags. You were 100% - the Colt mags run fine. Before going any further, did some analyzing of the difference in the two kinds of mags. Turns out that the Colt mag lips are 0.030 further apart. The right side lip was jamming into the bolt. And this was before I squeezed a few thousandths on the top so they would slide into the upper. Since it was only the right side of the mag that had bolt interference, I trimmed back that side until the bolt slid freely. Now everything is good and the Colt and ASC mags work in all the PCCs and my AR9 Pistol. I guess if you are going with different parts, even if you use quality, you may have to examine and adjust accordingly. Thanks to all for the help. I guess it is true that most problems come from the magazines.

OK, embarrassed here. After telling everyone that I was using my Colt mags, turns out I was using my ASC mags. Put in my Colt mags and problem disappeared. So, after putting on a little blue on both ASC mags and Matrix upper for checking, you were right, not enough clearance. Just a few thousandths. So, when comparing the Colt mags, the Colt mags taper a little sooner/more on the lips. With my bench vice and a little trial and error I soon had the ASC mags sliding in and out. But the bolt still had an interference. See next post.

Double post

I can believe that, but that holds for all shooters. I think PCC takes no extra time at all if you are prepared. I put my cased rifle against the berm when I am on deck. As soon as the range is clear, I uncase and walk to P1 with my rifle pointed up. As soon as the load and make ready command is given, just takes a few seconds to do that. And I have watched pistol shooters that go through all kinds of stuff before they are ready to shoot. We have all seen that. Taking extra time is an individual thing, anyone can load and make ready in a very short time.

I see. No, this is built as a pistol. 5.5 inch 3 lug barrel, pistol buffer tube with Tailhook Mod 1 and Law Tactical Folder. I have a fake 3 lug supressor until I decide whether to get a real one.

Didn't swap bolts, just uppers and lowers. I'll try it.