JGT

MemphisMechanic you make a great point. I agree that it makes sense (if you're going to build) to factor in the possibility that you might have problems. You should probably allow an extra cushion of budget, time, and patience. Depending on how badly you need it to run, it might be smarter to just buy the "insurance" of getting a known running product like a JP or MBX. Again, if I had a chance of winning I'd be thinking really long and hard about going ahead and buying that peace of mind. Also, if I lived in a remote area without any nearby gunsmiths or machinists to help me out in a pinch, I'd really hesitate to build. I would not want to start and get stuck with a non-functional project and nowhere to turn. In my particular case, I am lucky enough to live within miles of some great gunsmiths, and plenty of other shooters. I can definitely beg or bribe someone to help if I get in too deep. Since it's just a fun project and I enjoy tinkering then there doesn't seem to be much downside to trying a build. Even if I have an epic fail like cracking a pricey QC10 lower, I probably end up around the same total cost as the JP after replacement parts and labor. I assume there is some overlap between assembling 5.56 AR's and AR9's, so i have some chance of getting it done right the first try, especially thanks to all the fine folks on here kindly giving their expertise and experience. In that case i save a solid chunk of cash and get the satisfaction of doing it myself. I'm selling some stuff this week to fund the PCC project. I'll post on here whichever way I end up going. If I go with the frankenbuild and screw it up too badly then it can be used as a cautionary tale to show others what not to do! I promise to post pictures and give everyone a good laugh.

I see it sold out

Here's a build that I think could be competitive and reliable. I'm going to assume you buy the parts over time with small but not incredible discounts. You could do much better if you bought during major sales or had more parts laying around. I'm using current prices: CMC trigger- 165 Taccom complete upper- 500 QC10 lower- 250 LPK no trigger- 50 Taccom buffer- 85 Stock, grip- 50 (probably more if you buy both new but I'm going to assume we all probably have at least one stock or grip laying around) Buffer tube and castle nut: 30 Total: 1130 Alternatively: Factory CMMG guard 16"- 1050 CMC trigger- 165 Taccom buffer- 85 Stock, grip- 50 Total: 1350 For a JP GMR15, I think you're going to start around 1600 at best unless there's a discount I'm missing. Then you need a new handguard for 150 (minimum) and stock (assume free). Let's say 1750 total to get it where you're happy, and I think that is conservative. JP is more than 50% higher priced than frankengun if these numbers are even close to being right. I'm just trying to put some realistic numbers out there so we aren't comparing apples to oranges. $600 is three and a half cases of factory ammo (Blazer Brass), and at my level I guarantee you that 3.5 cases through a Frankengun in practice will get me placing better than paying up for a JP. Perhaps at a higher skill level I'd be able to wring an extra few percentage points of performance out of a better tool. I'm sure there are quite a few outstanding shooters in this very thread that would appreciate the difference, but I'm just not there yet. I think I'm leaning towards the Frankengun.

I'm still on the fence about what to get. Here's my current pros / cons based on all the feedback thus far, plus my own thoughts: MPX: softest shooting (recoil impulse and dot getting back on target) / but mainly proprietary parts, expensive, potentially mediocre reliability, frequent maintenance. Purely subjectively I don't like the way the stock handguard looks, diagonal cuts seem un-ergonomic to me. Sig USA has a mixed reputation but will probably stand behind the product. MBX, JP: guaranteed to work, good shooting characteristics out of the box, good support, parts interchangeability / but lower performance to dollar ratio than franken-ar9 Guard: innovative and superior operating system, softer shooting than a standard ar9, cheaper than MPX, JP or MBX / but proprietary parts, CMMG has a mixed reputation for support and doesn't seem to care as much about the competition market. Frankenbuild: can cherry-pick and tune the best parts, potentially lowest cost by a good margin, parts interchangeability, can match the softness and rapid dot re-aquisition of all but the MPX / but no support, more user tuning and work necessary, potentially unreliable or even nonfunctional if you don't pick the right components

I am debating between going open with the 19 or sticking in production with the 34. There's a bunch of really outstanding shooters at the local matches including GM's and national champs so either way I'm not gonna win, I just do it because it's so darn fun. The red dot is awesome though, I love that thing.

Yeah I was afraid of that. Looks like I'm out of luck on both counts! Thank you for the swift reply.

I've got a glock 19 rmr that I'd like to try out in the carry optics division. I've tried reading the rules and I think I know the answers to these questions but I'd like to know for sure before I show up to my next match. 1) I have a small ledge cut into the frame for my support-hand thumb. I've heard this called a thumb ledge / accelerator cut / gas-pedal. Is this legal in USPSA carry optics? If not, is there anything that can be done to make the gun legal for the division? It's actually my real carry gun, I didn't get it for USPSA. The cut isn't even that useful but I wanted to try it. 2) I switched up my belt for use in a specific outlaw match near me, and I have put a safariland UBL mid-ride drop on my holster (used to be mounted directly at the belt line). My glock 34 still has the heel of the butt of the grip above the top of the belt when holstered, but my glock 19 is very close to being even with the top of the belt, to possibly / marginally under the topmost level of the belt. Is this legal? If not I guess I'll switch it back, but I do like the slight drop. Thanks for the help, feels like you need a legal degree to interpret the written rules sometimes. Much easier when you just see it in person.

My issue with Sig and the MPX may or may not be totally rational, and I don't want to speak ill of anyone's chosen tool, but here are my own personal reasons why I'm not getting an MPX. I have no doubt that it is the softest shooting, but it does seem like Sig has a tendency to launch products before they are ready. Between the initial problems with the MPX, the 320 drop test fiasco, and the 365 striker drag / broken firing pin problems I do not have confidence in Sig as a brand. I'm never an early adopter, as you can tell from the fact that my first PCC will be purchased in 2019! I'm sure the majority of the issues have been ironed out by now, but nonetheless, I don't fully trust them. I have also read that the MPX is still not the most reliable platform. I've seen them go down at local matches several times (anecdotal evidence, I know) and I still read about people having problems with them on various forums. Finally, I don't like the lack of commonality with other platforms and being stuck relying on Sig for most parts. I know there's some parts interchangeability and aftermarket support but certainly not as much as AR9's or even the CMMG Guard. That means prices will stay high and there may not be as much innovation or iterative improvement over time. Business competition is what has gotten prices, reliability and performance to where they are today in 5.56 AR's. That's another reason I am finding it hard to spend much on a PCC, the price to performance is still several years behind the market in AR15 or precision rifle. I like the MCX/MPX operating system and if I could buy one from another company, or ideally multiple other companies, I probably would. From Sig, I will have to pass.

Thanks for all the great feedback, please keep it coming. I'm going to go with Glock over Colt and switch to 115gr based on replies thus far. I'm especially hoping to hear from those who have tested the CMMG radially-delayed as I want to start with the optimal operating system. Allow me to clarify my budget and thoughts on the JP GMR15 a little bit. I have no doubt that if I got one it would run perfectly. I read that something like half of top competitors are using them. That or the MBX pro series would be a great turnkey solution. However, I don't think either one is the "perfect" PCC out of the box. Another great example is the limcat Tron that just came out. I understand why these are built and priced how they are, but I believe based on what I've read here that you can get a functionally (not aesthetically) equivalent PCC for less if you're willing to tune it a bit. If I had GM skills and was playing for money, or I was depending on it to save my life, I'd go JP. Neither is the case for me. For example, I think the JP bolt and barrel are great but I don't see the SCS recommended much. From what I read here, most are recommending the blitzkrieg hd5015 hydraulic buffer plus heavy spring with added wave spring and spacers. As far as the upper receiver, I don't see any advantage to one brand over another unless it's a side charger. For the lower, it seems like QC10 is one of the most commonly recommended. I also would not choose the JP or MBX handguard, trigger, stock etc so again I'm paying top dollar for components I'd want to replace. The only complete factory gun I ever bought where I didn't replace a single part is the Armalite M15-3GN, which I only bought because I got it for such an amazing price that I could not assemble a similar rifle cheaper. In general I think a build from parts is riskier with the AR9 where there is no agreed-upon spec, but some combinations of parts must have potential to run reliably. As with the AR15, if you don't choose the parts carefully your Frankengun will experience tolerance stacking or outright incompatibility between components. Overall I'm leaning towards a lot of Taccom parts because they seem to be putting out innovative, quality components at a very reasonable cost and having the majority of operating components come from one source should cut down on problems. Again, I have no experience and this is all based on reading the forum so please do step in and set me straight if I'm off base!

Longtime reader but this is my first time posting. I'm going to get into USPSA PCC and need a 9mm carbine. I've done some research including review past PCC threads, but I could use input from the hive mind. My budget is <1400 total including mags, extensions, belt pouches. I already have a good optic. Here are my thoughts, please correct me if I have made any mistakes, I'm here to learn! 1) I shoot glock but I have no 33 rounders. Should I go colt or glock for the lower? Either way I'll purchase two or three mags and two or three extended baseplates. Colt gives you potential ambi and better angle plus slightly cheaper mags. On the other hand I have no plans to give up shooting glocks and commonality is nice. I have seen both colt and glock at local matches. 2) The CMMG radially-delayed system is appealing, should I get this and add a better buffer (but which one ??) I have read several threads and it seems like the recoil reduction over straight blowback is marginal but there may be some reliability advantage. Whats the latest thinking on this? Does anyone have solid experience with both and recommend one over the other? 3) I don't like Sig and don't want an MPX. I also don't want a Ruger PC carbine. 4) If CMMG Guard isn't the bees knees, I will just assemble a standard AR9. I've seen some threads with build lists, but here are the components I'm leaning toward: -Taccom complete 14.5 upper with extreme feed ramp, extreme bolt, and pinned comp -QC10 lower -taccom multistage buffer with short stroke kit OR blitzkrieg hydraulic buffer with JP 308 spring (again, if you have experience with both please post your thoughts) 5) JP GMR15 is probably awesome but seems overpriced for a 9mm blowback, especially if I start swapping out parts. My 5.56 competition rifle cost significantly less than a GMR15. 6) I understand that ammo can affect the choice of operating components, so here's my situation. I do not handload, and I don't plan to start. I shoot pretty much exclusively blazer brass 124 or sometimes 115. I'd be open to switch to a different factory ammo if someone gave me a compelling logical reason to do so, but I've had zero malfunctions in thousands of rounds and i can get it cheap so I see no reason to switch. Please give me some feedback on colt vs glock lowers, CMMG radially delayed vs straight blowback, and AR9 build components. I can figure out the ergonomic stuff like triggers and handguards on my own, but I need input on the operating components as I have no experience at all with the AR9 platform. I want something where the dot settles fast between shots, it's fun to shoot, and it's reliable. A lot of the PCC threads are a bit dated (I missed the PCC boom in '17-18) and it seems like new stuff has come out, so I'm curious to hear what the latest "state of the art" build might look like. Thank you!