JP-5 reviews/input

[aRjayboy]

2 hours ago, Stefan77 said:

Great question!  I would like to know myself. 

Heres the answer i got from JP Facebook page. Its a bit cryptic but i guess they seem to be saying to just use the standard 

[Walli]

Aren’t the rollers for changing headspace and the locking-pieces for changing the resistance it takes to open the action?

[Darqusoull13]

The lock pieces are the only thing you should really consider to tune the JP-5 to your liking / ammo selection.

I have not had to replace my rollers, ever. 

[Stefan77]

On 9/26/2022 at 12:27 PM, mrvip27 said:

Interesting response from Max on his instagram.

 

he basically uses the 70* for everything and is tuning the recoil spring instead.

 

for 147g, he is using the lightest 80% spring

for 115g, he is using the strongest 110% ar-10 spring.

I wonder if the AR springs would work?

[Boomstick303]

44 minutes ago, Stefan77 said:

I wonder if the AR springs would work?

 

As long as its a SCS type spring most likely.

 

What I don't know is if the springs for the JP5 SCS are the same springs as the original SCS.  I assume they are but I have not fleshed that out.  

 

At a quick glance at the JP website, I think Max is talking about an AR spring.  

 

• JPSCS-SPRING15-80: 1 side white

Edited November 22, 2022 by Boomstick303

[mrvip27]

2 hours ago, Stefan77 said:

I wonder if the AR springs would work?

 

yes sorry. the 80% only comes in an ar-15 spring. (if i looked correctly)

[lwshack]

6 hours ago, CClassForLife said:

For those who don't want to wait 16 weeks, ShootersConnection has a steel challenge configuration in stock.

 

https://www.shootersconnectionstore.com/Browse-by-Manufacturer/JP-Rifles/JP-Rifles-and-Uppers/JP-5-Roller-Delayed-9mm-Carbine-Steel-Challenge

 

6 hours ago, eerw said:

interested if Boomstick303 passes

 

Order it Monday morning from Shooter’s connection, in my hands 1 PM today. 

[BartCarter]

10 hours ago, aRjayboy said:

I was looking at the JP-5 components part of the website and i noticed in the roller replacement kit that they are offering different sizes:

* -4 (7.96mm)

* -2 (7.98mm)

* Standard (8.00mm)

* +2 (8.02mm)

* +4 (8.04mm)

 

is the sizes dependent on the power factor of your bullet just like in the lock pieces? 

 

I think the different sizes are available to adjust for proper clearance.

[Stefan77]

17 hours ago, mrvip27 said:

 

yes sorry. the 80% only comes in an ar-15 spring. (if i looked correctly)

I'll have to experiment when I can get some time.

[mrvip27]

13 hours ago, BartCarter said:

I think the different sizes are available to adjust for proper clearance.

 

Yes. Correct. Do not mess with the rollers unless you need to. Adjust locking pieces.

[aRjayboy]

On 11/23/2022 at 11:11 AM, BartCarter said:

I think the different sizes are available to adjust for proper clearance.

Clearance of what?  

[Boomstick303]

5 hours ago, aRjayboy said:

Clearance of what?

 

From what I have read it would seem like Headspace of the bolt to the barrel fit.

[aRjayboy]

6 hours ago, Boomstick303 said:

 

From what I have read it would seem like Headspace of the bolt to the barrel fit.

 

Thank you for the information 

[GrumpyNO]

Well. Got my JP-5 Yesterday. Mounted a Si Sauer Romeo 3XL with riser mount and a Techwell magwell. Cleaned the barrel and went to the range today. Zeroed and did a few quick drills. Didn't have much time, going back for more in the weekend. But holy cow, people are not joking about how flat shooting this thing is. Compared to the direct blowback rifles I've tried before, this is something else entirely. This is what I was hoping for, but I thought it might have sounded too good to be true. Not so. This is the real deal ... Looking forward to practice some more. Got my first match coming up this Sunday already.

[Blackstone45]

Any idea how many days JP are closed for Thanksgiving?

[Darqusoull13]

9 hours ago, Blackstone45 said:

Any idea how many days JP are closed for Thanksgiving?

Online never closes

[OhioGunner]

JP has a 10% off BF sale right now, and Smoke Composites has a 25% off sale if anyone is looking for accessories

[Stefan77]

So I played around a little yesterday.

60*:

115grn Blazer Brass cycled and bolt would hold open (I had a couple of times that it didn't hold the bolt open).

130grn Syntech, bolt cycled but would not hold open.

150grn syntech, bolt would not cycle

 

70*:

130grn Syntech I noticed a little more recoil, bolt cycled and held open

150grn Syntech, bolt cycled and it held open but I can't remember if it was consistent.

 

As far as what felt good to me?

 The 115grn BB felt really nice.  Cycled fast and felt light (what I mean by light is that it wasn't a heavy'sh push)

The 130grn Syntech was pretty good, it shot well.  I was happy with it but I don't like the bolt not holding open.

150grn Syntech felt a little sluggish when shooting it.

 

These are just my "feels" so not a really objective thing.  

 

I just ordered the Eley Trial pack and will test that out.  I ordered a case of Federal 115grn FMJ to try which shoot at 1180FPS (from a pistol) vs the BB 115grn which shoots at 1145fps (from a pistol).  The 130grn Syntechs are listed at 1140 FPS from a PCC with a 16" barrel so I suspect a slower velocity from the JP5 being it is not a true 16" barrel with a pinned and welded muzzle break.  

Thoughts?

Edited November 28, 2022 by Stefan77

[mrvip27]

On 11/28/2022 at 10:48 AM, Stefan77 said:

So I played around a little yesterday.

60*:

115grn Blazer Brass cycled and bolt would hold open (I had a couple of times that it didn't hold the bolt open).

130grn Syntech, bolt cycled but would not hold open.

150grn syntech, bolt would not cycle

 

70*:

130grn Syntech I noticed a little more recoil, bolt cycled and held open

150grn Syntech, bolt cycled and it held open but I can't remember if it was consistent.

 

As far as what felt good to me?

 The 115grn BB felt really nice.  Cycled fast and felt light (what I mean by light is that it wasn't a heavy'sh push)

The 130grn Syntech was pretty good, it shot well.  I was happy with it but I don't like the bolt not holding open.

150grn Syntech felt a little sluggish when shooting it.

 

These are just my "feels" so not a really objective thing.  

 

I just ordered the Eley Trial pack and will test that out.  I ordered a case of Federal 115grn FMJ to try which shoot at 1180FPS (from a pistol) vs the BB 115grn which shoots at 1145fps (from a pistol).  The 130grn Syntechs are listed at 1140 FPS from a PCC with a 16" barrel so I suspect a slower velocity from the JP5 being it is not a true 16" barrel with a pinned and welded muzzle break.  

Thoughts?

 

Thanks for the input. Keep us updated on the Eley.

[Blackstone45]

How quickly are JP typically responding to specific build queries? (and not lead-time or "what is my rifle" questions)

[Darqusoull13]

2 hours ago, Blackstone45 said:

How quickly are JP typically responding to specific build queries? (and not lead-time or "what is my rifle" questions)

What do you want to know? 

 

[Blackstone45]

37 minutes ago, Darqusoull13 said:

What do you want to know? 

 

Trying to get the length of just the JP-5 upper receiver with naked buffer tube and no barrel.

[Stefan77]

On 11/29/2022 at 12:04 PM, mrvip27 said:

 

Thanks for the input. Keep us updated on the Eley.

Will do.

[DwightSchrute]

On 11/24/2022 at 2:59 PM, GrumpyNO said:

But holy cow, people are not joking about how flat shooting this thing is. Compared to the direct blowback rifles I've tried before, this is something else entirely. This is what I was hoping for, but I thought it might have sounded too good to be true. Not so. This is the real deal ...

Mine isn’t expected to arrive until February, but this is music to my ears!

[DocMedic]

I ran a RCM branded 60* Lock Block this past weekend with the M882 ammo, and this has been my experience so far. I ended up doing about 300 rounds of testing indoors and only had one FTEject after I want to say the 5th or 8th round fired. Afterwards I went to clean the JP5 out and it ran flawlessly. Then I went to shoot a outdoor match the next day.

 

The temperatures hovered above 35, and on the first two stages I had issues. On the first stage I had a failure to Load from the magazine after the 3rd shot, at the time I didn't think much of it as I forgot to bring my normal mags with me and the only 2 mags I had was one 31 round glock mag, and a MBX 155 with long extension that i haven't tested yet. I figured the the FTL was due to not breaking in the MBX mag prior to the match, so I did a rerack and shot the rest of the stage with no issues. On the second stage, I experienced a similar failure to eject that I did the day prior during testing. After that I replaced the 60* block back with the original 80* block and didn't have any issues for the rest of the match (Gun wise anyways, mentally is a different story) 

 

I think with warmer weather and warmer ammo the 60* block would run with no issues. The Indoor range was about 70 degrees with the ammo being in the office all day, were when I shot the match the next day everything was just cold. Its a pity, the 60* block with M882 ran as soft as it did with the MPX maybe even a bit softer, but the setup at least for now is to unreliable. I want to try a 70* block but JP doesn't sell directly to Colorado Shooters, so I can't order online from them and none of their distributors are currently stocking JP5 Locking blocks. What makes the matters worst is HK No.29 locking Blocks are impossible to find also.

 

I want to put another 2k rounds through this before the start of new year before I give the JP5 a honest review, so far when I got it last month I think I'm around 2.5k-3k rounds fired (need to look at my notes) on it between testing practice and matches.

Edited December 7, 2022 by DocMedic