JP-5 reviews/input

[DocMedic]

21 minutes ago, Boomstick303 said:

I have not been able to get the JP5 to run reliably with the 70 degree lock piece with any ammo having a PF of 140 and less.  This is with the stock SCS Spring.  I run the 80 degree lock piece and have had zero failures.  I cannot see the need for the 60 degree lock piece unless you were shooting some seriously hot 9 mm ammo.  

 

I was trying out a 60* Lock piece with 124gr at PF of 158-161, and it wasn't enough to run 100% reliable. possibly changing out to lighter spring in the the SCS would had helped but technically the 60* Lock was made for HK's that were using 40s&w.

 

[Darqusoull13]

33 minutes ago, Boomstick303 said:

I have not been able to get the JP5 to run reliably with the 70 degree lock piece with any ammo having a PF of 140 and less.  This is with the stock SCS Spring.  I run the 80 degree lock piece and have had zero failures.  I cannot see the need for the 60 degree lock piece unless you were shooting some seriously hot 9 mm ammo.  

About the only person I know that has needed the 60 is a dude on the CBP team that was running duty ammo. It was soft 

[Heniv77]

7 hours ago, DwightSchrute said:

I had a match-killing failure to eject using 130 PF rounds with a 70-degree lock piece.  I went back to the 80-degree lock piece and haven’t had any problems.  You might be tempting fate with 60-degree lock piece for PFs in the 130s.

 

What OAL are you loading the HAPs to?  Several years ago, I called Hornady and they said to use XTP data for the HAPs.  They recommended 1.060” for the XTPs, which seemed rather short to me.  It’s the only reason I shied away from the HAPs at the time.  A couple of months ago, I found some of of the unloaded HAPs in my workshop, so I loaded a few without changing my 1.120” FMJ seating die, and they came out to 1.085”.  I worked up a ladder with N340 from 4.0 to 4.6, and to make a long story short, 125 grain HAPs with 4.3 grains of N340 at 1.085” averaged 132.5 PF in my JP-5, and they felt great with the 80-degree lock piece.  Quiet power with smile-inducing accuracy is the best way to describe it.  I might get some 124 grain “competition style” bullets from Everglades (which look like a HAP copy, but are .355” and 124 grains instead of the HAP’s .356” and 125 grains) and make them my new match ammo.

Thanks, will test more before deciding on 60/70 lock for that load.

 

28.00mm OAL (1.102)

 

Agreed, really accurate as well.

[Heniv77]

7 hours ago, Boomstick303 said:

I have not been able to get the JP5 to run reliably with the 70 degree lock piece with any ammo having a PF of 140 and less.  This is with the stock SCS Spring.  I run the 80 degree lock piece and have had zero failures.  I cannot see the need for the 60 degree lock piece unless you were shooting some seriously hot 9 mm ammo.  

Maybe there is a difference somewhere in the config of SCS or something? I have a rifle from the second batch, with the new firing pin installed by the factory, and I only changed the locks. Will grab some photos of my SCS and post.

 

So far no ammo I have tested has failed to cycle perfectly with the 60 lock. 10k plus rounds. I have not been running any ammo that would be sub 125 PF if tested in a handgun and mostly stuff that chronos at 140-145ish in my JP-5.

 

Fiocchi 124gr FMJ factory ammo at around 150pf bottoms out the SCS with a hard slam at the end and feels terrible to shoot, so I considered getting a 50 lock for that load as I use it to harvest brass.

[brian45acp]

I spoke with Jp this week and one of their guys runs the 60 so I ordered one. He is 115gr and 148-150pf. My thought is the 60 with lightest spring and bump my load just a little to about 140pf. 
 

I’ve read so much on here about the 70 not working with 130pf and I run it perfectly so I’m going to figure it out myself. 

Edited August 17, 2023 by brian45acp

[Heniv77]

7 hours ago, DocMedic said:

 

I was trying out a 60* Lock piece with 124gr at PF of 158-161, and it wasn't enough to run 100% reliable. possibly changing out to lighter spring in the the SCS would had helped but technically the 60* Lock was made for HK's that were using 40s&w.

 

Strange! I know at least 4 others here in Sweden running the 60 lock with no issues with way lower pf ammo than that. My 136PF load might be on the edge though. Is there a difference between the rifles we get over here vs the ones provided in the US?

[Bdh821]

19 hours ago, Heniv77 said:

Strange! I know at least 4 others here in Sweden running the 60 lock with no issues with way lower pf ammo than that. My 136PF load might be on the edge though. Is there a difference between the rifles we get over here vs the ones provided in the US?

My only guess is they have lighter a SCS spring in it to cycle? 

[whan]

Picked up my JP5. Was able to shoot 100 rounds and zero the dot today, going to shoot my first PCC match on Sunday. Of course shoots very soft, running a 70 locker and both 124/115gr super Vel reloads without issue.

 

 

Not pictured below but was also able to get the Radian Talon 45deg safety installed. Like mentioned previously, you do need to remove the trigger assembly to get the OEM safety out. Otherwise works well - was a requirement for me since my AR has it, and I do practice using the safety on rifles during longer movement, and the 90deg throw is just a decent bit more difficult to re-engage the safety

 

 

 

After the match on Sunday, I also plan on trying to install a brekke/smoke composites maxamundi handguard. Anyone have any issues getting the factory tube off? My FFL who also had a gunsmith said a proprietary tool was needed...

[Z-Chaos-Factor]

22 minutes ago, whan said:

Picked up my JP5. Was able to shoot 100 rounds and zero the dot today, going to shoot my first PCC match on Sunday. Of course shoots very soft, running a 70 locker and both 124/115gr super Vel reloads without issue.

 

 

Not pictured below but was also able to get the Radian Talon 45deg safety installed. Like mentioned previously, you do need to remove the trigger assembly to get the OEM safety out. Otherwise works well - was a requirement for me since my AR has it, and I do practice using the safety on rifles during longer movement, and the 90deg throw is just a decent bit more difficult to re-engage the safety

 

 

 

After the match on Sunday, I also plan on trying to install a brekke/smoke composites maxamundi handguard. Anyone have any issues getting the factory tube off? My FFL who also had a gunsmith said a proprietary tool was needed...

Yes you need the assembly / dissambly wrench for it. Unless you want to jank it up or jimmy rig something. 

[brian45acp]

Haven’t hacked into my jp5 yet but this is what you need. I have it for my gmr13’s and apparently it’s the same process but on jp5 barrel doesn’t come out and most caution not to try either.

Talking to guys here about going all smoke products say it makes the rifle snappy. Jp also told me that going to light is a “thing”. I’m wanting stability and balance with the least dot movement so for now I don’t plan on going carbon fiber.  

 

Edited August 19, 2023 by brian45acp

[whan]

Thanks for the help guys - looks like I’ll need to order the wrench unless I can borrow one from someone at my local range that has one

 

For me I’m planning on just doing the handguard. Less so weight reduction overall vs reducing weight in front and shifting balance rearward. Plus I feel like that’s the setup Max has so can’t be too bad haha

Edited August 19, 2023 by whan

[Bdh821]

7 hours ago, brian45acp said:

Haven’t hacked into my jp5 yet but this is what you need. I have it for my gmr13’s and apparently it’s the same process but on jp5 barrel doesn’t come out and most caution not to try either.

Talking to guys here about going all smoke products say it makes the rifle snappy. Jp also told me that going to light is a “thing”. I’m wanting stability and balance with the least dot movement so for now I don’t plan on going carbon fiber.  

 

I’ve shot these back to back multiple times. The recoil difference is negligible. My suggestion that I tell my local friend, “stop dwelling on gear” and focus on shooting… 

[Z-Chaos-Factor]

12 hours ago, whan said:

Thanks for the help guys - looks like I’ll need to order the wrench unless I can borrow one from someone at my local range that has one

 

For me I’m planning on just doing the handguard. Less so weight reduction overall vs reducing weight in front and shifting balance rearward. Plus I feel like that’s the setup Max has so can’t be too bad haha

Balance is more important to me than overall weight. It helps with overall movement having a balanced gun. Beyond that light or heavy is meh, especially with the JP5. 

 

Also Max is a special human and trying to do what he does isnt always a recipe for success. 

[brian45acp]

19 hours ago, Bdh821 said:

I’ve shot these back to back multiple times. The recoil difference is negligible. My suggestion that I tell my local friend, “stop dwelling on gear” and focus on shooting… 

Depends where you are at and I agree. I spent since 2017 with a stock gmr13 and only this year did I down tune the SCS and drop from a 148pf to 130pf. It helped my game a ton. I’m at a point where I can utilize these small differences now and it’s taken a long time to get there.

 

I’m not decided on a full Smoke outfit or not. I did just receive my 60 lock and springs so I’m going to play with combos. The 70 had been running great despite guys here saying it’s iffy. Shot with a guy yesterday running 60 lock and he had ammo issues but it ran. The squibs were his fault not the guns. When it did run the brass dribbled out but his loads so weak. Point being most here say 60 lock is no good. Talked to JP and their guy uses the 60 just fine. I come here for the best info from experienced guys but I’m starting to see it’s getting to be like other forums lol. This last statement not directed at you but just being a general statement. Nice pair jp5s by the way.

 

 

Edited August 20, 2023 by brian45acp

[Bdh821]

3 minutes ago, brian45acp said:

I come here for the best info from experienced guys but I’m starting to see it’s getting to be like other forums lol.

 

 

Hmmm, I must not know what I’m talking about 

[Z-Chaos-Factor]

2 hours ago, Bdh821 said:

Hmmm, I must not know what I’m talking about 

Hmm 4th at nationals? Yeah doesnt look like it.

 

https://youtu.be/ncAZjFj5ahM

[Bdh821]

1 hour ago, Z-Chaos-Factor said:

Hmm 4th at nationals? Yeah doesnt look like it.

 

https://youtu.be/ncAZjFj5ahM

That doesn’t count. I used a MPX

 

 

Back to the JP5 subject, I tried the Max locker/spring setup with similar PF ammo.  Brass basically dribbled out of the gun. I just tested lockers and scs springs until I found a combo that was reminiscent of my MPX

[Z-Chaos-Factor]

3 minutes ago, Bdh821 said:

That doesn’t count. I used a MPX

 

 

Back to the JP5 subject, I tried the Max locker/spring setup with similar PF ammo.  Brass basically dribbled out of the gun. I just tested lockers and scs springs until I found a combo that was reminiscent of my MPX

I didnt care for the max combo the Ar10 was too strong for me.  Made the gun jumpy. 

 

I have since messed with the SCS, unrivaled buffer finally settled on a kynshot buffer and standard spring. But all in the changes werent that dastric from one to the other. 

 

Ive gotten better a shooter by not messing with it and just shooting.  

[whan]

Some good news and some bad news. Good news is I got the smoke composites handguard installed, as a friend at the range actually had the JP barrel nut tool and was able to get it from him.

 

Bad news is I tried shooting a match today, not having been able to test fire after installing the radian safety. I guess I didn't reinstall the ejector pin retaining clip correctly, and it fell out at some point during the first stage, along with the ejector pin itself. Of course the gun stopped working immediately as the ejector no longer was in the proper place. Searched all over and couldn't find the pin, so now have to wait for the new one I ordered from JP to arrive...

 

 

[brian45acp]

6 hours ago, Bdh821 said:

Hmmm, I must not know what I’m talking about 

You must not have read it all. I said good advice and I agree. But most posts I’ve seen saying what doesn’t work clearly does regarding lock pieces etc. 

 

I am still curious about the smoke products but think it’s a cool upgrade not a functional one. A guy yesterday had his rifle insane light with titanium bolts and pins in addition to all the smoke items. He said it felt too jumpy. I’ll shoot it next week and see. The crap is all so subjective it’s hard to ask others about.

 

Edited August 20, 2023 by brian45acp

[RedDotsOnly]

Multiple friends of mine have them and they're quite great to shoot - Make shooting easy

[brian45acp]

2 hours ago, Z-Chaos-Factor said:

I didnt care for the max combo the Ar10 was too strong for me.  Made the gun jumpy. 

 

I have since messed with the SCS, unrivaled buffer finally settled on a kynshot buffer and standard spring. But all in the changes werent that dastric from one to the other. 

 

Ive gotten better a shooter by not messing with it and just shooting.  

You tried the hydraulic buffer in the jp5? I have it in my bag for next week to practice with. I installed it here at the house and noticed it sticks at full compression and I have to jiggle the charge handle. 

[Z-Chaos-Factor]

12 minutes ago, brian45acp said:

You tried the hydraulic buffer in the jp5? I have it in my bag for next week to practice with. I installed it here at the house and noticed it sticks at full compression and I have to jiggle the charge handle. 

You have to put spacers behind the spring otherwise the travel distance is way too long and the gun will lock up on you. 

 

But yes I'm running the kynshot Ar15 buffer for light recoiling rounds. 

 

 

[brian45acp]

I think I know what you mean. Have a pic? 
 

I imagine jp5 with hydraulic buffer would feel amazing. I did notice it’s heavier that the SCS though.

 

 

[Z-Chaos-Factor]

23 minutes ago, brian45acp said:

I think I know what you mean. Have a pic? 
 

I imagine jp5 with hydraulic buffer would feel amazing. I did notice it’s heavier that the SCS though.

 

 

Heres a rough idea. You can just put quarters behind the spring as well. But you will want to measure and match the stroke length/ travel distance of the SCS its not a full stroke length. 

 

The kynshot is heavier than the SCS by like 2 ounces. But the kynshot makes up for it. I think its better than just the plain SCS but not anything game changing. But you will want to use the stock 80 locker. Or maybe even a 90 but I am running the 80. 

 

 

Edited August 20, 2023 by Z-Chaos-Factor