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Help configuring a jp gmr-15?


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I shoot 2 and 3gun, no steel challenge style matches.  I am thinking about a 14.5 barrel and possibly the titanium compensator upgrade(. I have heard of erosion problems with 223 but I will be shooting coated lead 9mm) does this make sense for weight savings and ability to swing the gun or would the heavier steel comp hold the barrel down for double tap paper targets?

 

my plan is to short stroke the buffer system.  The upagrade for 2 tungsten is $50 for all 5 tungsten is $110?  I am hoping to use the same ammo 135 gr with wst powder that I use in my pistols.  I know I could order additional tungsten afterward but I would like the one and done option.

 

trigger I was going to spend $0 and opt for the 3-3.5 traditional competition trigger and not $125?for the cartridge style JP


other options would be extended mag release$10 and Ambi safety with short right side$15.  I think my main concerns are around the barrel comp material and number of tungsten short stroke weights.  I  have been shooting an mpx and it is soft and would like it to feel as close to that as possible or better?

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I believe Josh Froelich uses the titanium compensator on his JP. Less weight on the front of the gun is always nice. I haven't heard anything bad about the stainless comp though. However, I do believe that JP is coming out with a new PCC focused comp in 2020. It has 2 ports on top compared to the current style. Short stroke is definitely the way to go, though I'm not too versed with different loads and weights.

 

Extended mag release and short right side safety are great choices. Also new for 2020, their standard trigger will be able to accept their modular trigger shoes. I'm not sure if it's up in the rifle builder yet though.

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I have the 5 steel in mine with the standard stainless comp and I like it fine. I also got the stainless bolt, so much easier to clean. And yes, get the extended mag release and two sided safety. I just have the standard size on both sides and it works fine for me. The standard comp trigger is perfect for me also.

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My GMR-15 has the Ultra Lite barrel, short stroke bolt & buffer (3 SS & 2 tung), ambi safety with std profile left side/low profile right.  It also has their standard 3 1/2 lbs trigger.  It has the std mag release.  It's the one thing I might upgrade.

 

It shoots 115 MGB JHP reloads and Speer Lawman 115 TMJ's both at 1200 +/- fps into 1" - 1 1/4" groups at 25 yds.

 

It's my first PCC, so I can''t compare the recoil impulse to other blow back guns or the MPX, but the dot doesn't leave the upper A zone at 15 yds.

 

FYI, it is one of the Ready Rifles purchased from Shooters Connection.  I was too impatient to wait for one to be built.

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Sounds like a good plan - I have the 14.5 with ss pinned comp - I didn't really consider the titanium comp, but probably should have.  I can say there is a lot of carbon build-up that is a pain to clean, not sure if titanium is as durable as SS?  I went with two tungsten on the short stroke based on a recommendation from Adam at JP.  No recoil, steady dot. I shoot Federal 124g exclusively - mostly to stay consistent with my pistol which can have light primer strikes occasionally - the soft fed primers take care of that.  If the load you are shooting is pretty mild you could get away with less tungsten I think, less mass, even less recoil? 

 

I chose the Cartridge type trigger because I like wanted to be able to swap easily - love it. The mid-sized ambi safety kept catching my right hand so I changed that to the smallest one on the right side - took care of the issue.  

 

I'm at about 2000 rounds - did have one failure to eject - cleared easily - otherwise perfect.  Others in PCC that I shoot with can't say the same, they have a lot more drama than I like.  

 

One last thing - as much as I like the JP hand guard (I have the one with the slots), I would look hard at the new M-lok ones they are supposed to be coming out with.  Can't fit ANY aftermarket angled grips or anything without a bulky picatinny rail adaptor to fit this rail - I'm using the JP handstop - works OK but not ideal.  

 

Good luck!

 

Phil

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I have researched titanium vs stainless steel and I see titanium is much softer and I’m thinking I might damage when cleaning the comp.  I shoot coated lead exclusively in pistol ammo.  

I don’t really want to wait to purchase my jp because my tax money will vaporize but I like the idea of a few new options coming out like the replaceable trigger shoe, compensator with upper  facing ports and new handguards becoming available this year.

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The handguard was supposed to be available last year when I ordered mine. We're still waiting. I put a Smoke Composites handguard on mine and I love it, WAY lighter than the standard jp handguard and looks better too. When you order tell jp you want a barrel nut tool. It's free, but you have to ask for it.

My stainless comp works just fine too.

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On 3/6/2020 at 5:13 PM, bzajdek said:

I shoot 2 and 3gun, no steel challenge style matches.  I am thinking about a 14.5 barrel and possibly the titanium compensator upgrade(. I have heard of erosion problems with 223 but I will be shooting coated lead 9mm) does this make sense for weight savings and ability to swing the gun or would the heavier steel comp hold the barrel down for double tap paper targets?

 

my plan is to short stroke the buffer system.  The upagrade for 2 tungsten is $50 for all 5 tungsten is $110?  I am hoping to use the same ammo 135 gr with wst powder that I use in my pistols.  I know I could order additional tungsten afterward but I would like the one and done option.

 

trigger I was going to spend $0 and opt for the 3-3.5 traditional competition trigger and not $125?for the cartridge style JP


other options would be extended mag release$10 and Ambi safety with short right side$15.  I think my main concerns are around the barrel comp material and number of tungsten short stroke weights.  I  have been shooting an mpx and it is soft and would like it to feel as close to that as possible or better?

If you are going ultralight titanium comp will save a small amount of weight. No erosion with 9mm to worry about. 

 

2 tungsten is a nice middle of the road and definitely soft. I like 5 stainless but everyone is pretty spread out on the exact numbers of weights for optimal setups. 

 

Standard comp trigger is excellent. Definitely add the extended mag release. Inexpensive and super useful.

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