-
Having trouble using the site?
Contact support
Anyone get a preorder in for the new JP5? I have an HK SP5, but thinking of putting an an order for the JP as well.
- Thread starter AwesomeDude
- Start date
I'm real close to getting in, but I want to shoot one "in the wild" first.
I've had a bunch of different 9mm PCC's over the last few years, including a GMR-15 and a couple fully blown MPX's... and sometimes the fancy ones aren't the fastest and/or easiest to live with. So that said, I'm a little skeptical if the cost and complexity of the roller-delayed system is really worth dealing with pragmatically..?
I've found there's beauty in the simplicity of the dumb caveman blowback system, especially when it comes to a gun I'm going to beat the piss out of and regularly put hundreds and hundreds of rounds through each session.
I've had a bunch of different 9mm PCC's over the last few years, including a GMR-15 and a couple fully blown MPX's... and sometimes the fancy ones aren't the fastest and/or easiest to live with. So that said, I'm a little skeptical if the cost and complexity of the roller-delayed system is really worth dealing with pragmatically..?
I've found there's beauty in the simplicity of the dumb caveman blowback system, especially when it comes to a gun I'm going to beat the piss out of and regularly put hundreds and hundreds of rounds through each session.
I love that someone finally dove into a system better than direct blow back. I know it’s simple and fairly reliable. But, the smoothness of a roller delayed system in an AR will be awesome.
I also do worry that it will be a little finicky due to how much they had to alter the original HK design in order to fit it into the AR. I also don’t understand why they went with Glock mags. You going to all the trouble and r&d to make a roller system. Why not make a lower that takes smg mags, scorpion or MPX. So you get lock back but better feeding and a easier mag to deal with. I know Glock mags are cheeper and easier to find.
I also do worry that it will be a little finicky due to how much they had to alter the original HK design in order to fit it into the AR. I also don’t understand why they went with Glock mags. You going to all the trouble and r&d to make a roller system. Why not make a lower that takes smg mags, scorpion or MPX. So you get lock back but better feeding and a easier mag to deal with. I know Glock mags are cheeper and easier to find.
Yeah, I'm a little weary...
Yes, MP5's are a blast, but their triggers are shit and the ergos are pretty terrible, and once you get over the Die Hard fun, they are kind of expensive for what actually isn't a great package by more modern AR-Barbie-for-Men standards and it's not really a viable platform if you want to go play run and gun games' PCC divisions... I have owned and sold a few and don't miss them.
...but yeah, roller-delayed feels fucking awesome, so I hope they've got it figured out. (?) Just after all the crap I dealt with and had to figure out running an MPX, sometimes that sort of awesome can come at a price.
Using the MPX as an example: the MPX's gas-piston system feels so damn amazing compared to caveman blowback, way more Gucci, but only for as long as how ever many rounds it lasts until it's too dirty and not getting enough gas... and then suddenly you've got an expensive piece of crap that runs like shit until you clean the sucker (takes forever to clean them properly too)... I don't want to go through that again.
The Lancer-made MPX mags are awesome though, I totally agree that JP should have used those or the Scorpion mags, instead of Glock mags, they just seem better suited for the job IMO. That said, I have a Foxtrot Mike lower that's seen thousands of rounds without any problems at all, and even short-stroked with $1.50 in quarters, it still locks back on empty every single time... so it can be done with Glock mags.
JP does weird shit sometimes though, and gets away with it too: like their furniture options are mostly total crap and every one ends up changing it out right away, but they still send you your expensive gat with that old crappy shallow-angle Hogue A2 grip most stopped using years ago, and some outdated hand guard and stock you need to change.
I don't mean to keep saying "expensive" like I'm cheap, I'm not, these guns are so hilariously fun I don't mind spending whatever it takes for more smiles and laughs... it's just that I'd rather have a cheaper gun like a ~$700 blowback AR9 with a $200 trigger and $200 hydraulic buffer system that just runs and runs (so the shredding doesn't get interrupted) over a fancy gun that chokes.
So IDK, weary...
Last edited:
I’ve got no problem with Glock mags. Add small TF, or big TF or TT basepads, use ETS mags, use glock 17 mags for classifiers, it just doesn’t matter. All three (2 are JP and 1 Leadstar) just run and run and run. Too much fun.
Glock, AR15/10 mags are the most prolific, I’d want my rifle/pistol to use mags that are common.
I mean, CMMG has been doing delayed blowback in ARs for a bit now with great success and literally can't keep up with orders, and you can use nearly any magazine you like with theirs as well: endomags; colt mags, M&P, glock or P320 mags with an insert block; or use a glock or P320 mag native lower.
if I didn't already have a scorpion and didn't mind the buffer tube problem of the AR platform the CMMG design would be my first stop. the only area where JP might have an edge over CMMG's RDB design is if you can replace the rollers for ones with a different locking angle for better suppressed performance, similar to how you can with MP5/SP5s
How many rounds are you shooting until your MPX starts running like crap? Do you have the K version, 8” version or 16” version? I have the 8” version and it runs great. Haven't had issues with it running like crap after long sessions, and I normally run it suppressed. But I also had the gas port opened up and installed an adjustable gas plug on it. I haven‘t found cleaning it to be too bad either. Maybe I just like cleaning it.
I hadn't heard about the JP 5 until I saw this thread.
I've got a little cmmg "pistol" I built with their bolt / barrel kit and it's super fun. It's always how I introduce non gun folks to AR15s, as it's super soft shooting and no need for ears with 147s and a can.
The JP interests me, but not in a 14.5.
I don't do PCC comps, but I'd like to buy a pistol to form 1.
I'm curious how flexible the system will be suppressed / naked 115 / 124 +P / 147
I've got a little cmmg "pistol" I built with their bolt / barrel kit and it's super fun. It's always how I introduce non gun folks to AR15s, as it's super soft shooting and no need for ears with 147s and a can.
The JP interests me, but not in a 14.5.
I don't do PCC comps, but I'd like to buy a pistol to form 1.
I'm curious how flexible the system will be suppressed / naked 115 / 124 +P / 147
How many rounds are you shooting until your MPX starts running like crap? Do you have the K version, 8” version or 16” version? I have the 8” version and it runs great. Haven't had issues with it running like crap after long sessions, and I normally run it suppressed. But I also had the gas port opened up and installed an adjustable gas plug on it. I haven‘t found cleaning it to be too bad either. Maybe I just like cleaning it.
Latest version. Sometimes it'd go as much as 300-400rds without starting to quit on me, but usually it was much less than that.
Shooting soft bunny-fart loads (like one would want to for USPSA, say ~130pf out of a Shadow 2, maybe ~145pf out of a 16" PCC) it'd barely spit 200 before it'd start fucking up. Stronger PF factory stuff would go longer, but that was still a fairly short pitch-count. I literally tried everything In lead We Trust makes, gas plug stuff, springs, you name it, and it still was pretty unreliable regardless of what parts combos I was running.
When it worked, it was awesome though. Just got to be too frustrating to deal with shooting a high volume of rounds.
Sucks man. Yeah, I’m normally running 124, 147 or 158gr ammo. Maybe it doesn’t like the light stuff. I normally go to the range with 10+ fully loaded 30 round Sig/Lancer mags. No issues going through the entire range session with it. But again, 95% of the time it’s suppressed.
The thing with the CMMG's radial delayed blowback (radial, NOT roller-delayed) is that if it was "the shit", then every other dude in USPSA PCC would already be running one because it's been out for years and doesn't cost much more than boring old blowback... but they're not. I'm never the guy who gets accused of following the crowd, but that kind of tells me everything I need to know. I only know of one really good shooter/competitor in my state (TN) who fought with one for a long time and thousands of rounds before he finally gave up on it.
IIRC, from what I understand, the problem is that CMMG's radial delayed blowback system doesn't end up feeling that drastically different from straight-up caveman blowback... except you end up with sort of a "unicorn" of an operating system and the proprietary nature/issues that go with that.
I haven't really run anything lighter than 124's, my usual load uses Blue Bullets' 135gr TC (truncated cone) .356, 3.4gr Sport Pistol, Federal GMM SPP. I have run a boatload of S&B 124's and the Syntech PCC 130's too (thousands) and it would still quit on me. The only time I ever really shoot 115's is when I send 1-3 downrange every ~few/five hundred rounds to help out with cleaning the barrel and keeping the Blue's from leading things up too bad (I try to keep a 50rd box of factory stuff in my bag just for that purpose).
Shooting suppressed, the added backpressure might actually help the MPX, IDK... in my experience, my 16" unsuppressed and with a comp on the end, was actually quieter than my buddy's 8" MPX + a can... the 16" 9mm's are actually too quiet for the shot timers a lot of the time, so I've never tried a can on one.
Last edited:
Didn't realize we were specifying competition. PCCs are range toys to me so that was what my response stemmed from.
Ok, I will preface this by saying I am sponsored by JP and am a multi-division GM in Steel Challenge. I have been shooting a JP GMR-15 Ultralight for about 2 years. It is an incredible rifle, and as reliable as they come. The JP5 is wicked. I have seen and shot it in the wild. It is light, fast, and shoots as flat as anything I have ever shot. If you are wanting the fastest, flattest PCC out there, then the JP5 is your animal. If you are not competing and just want a great PCC that is extremely reliable, you can save some coin with the GMR-15.
Shooting them back to back is a pretty significant difference. I agree it can be finicky though. I have mixed feelings but it sure beats the heck out of 300 blackout for doing the subsonic giggle thing.
This is not keeping with my experience. I had the pleasure of being an RSO for a suppressor demo put on by Sig with very early MPX and MCXs, both with suppressors. The MPX saw well over a thousand rounds, without added lubricant and had no stoppages all day. It was a Gen 1 8in variety.
I have also had the opportunity to shoot a JP5. It was very smooth and well made. I only put about 50 rounds through it and didn’t have any PCCs at the range to shoot side by side. It was lighter shooting than the Sig 516 with OSS suppressor that was my main squeeze that day. If you are okay with a carbine that takes Glock mags I imagine it is a good choice.
