JP Enterprises

JP Enterprise Silent Captured Spring

Written by: Michael Caprioli


  I’ve been interested in since they first appeared in 2012. It’s a buffer spring and a buffer, it’s two – two items in one!  The JP Enterprise Silent Captured Spring is genius!  The system uses a spring like a 1911 recoil spring around an aluminum rod with adjustable weights at the BCG mating side with a cone like base at the rear of the unit.  

  JP Enterprise puts a lot of research into their products and won’t release a product if it doesn’t work 100%.  Specifically, JP did a lot of research to see if there are any limitations to their SCS.

  There are two generations of the AR15 SCS – First and Second.  The difference being the first generation uses a steel guide rod, are metric (M5) and take a 3mm hex key.  The second generation uses an aluminum guide rod and a 1/8 hex wrench.

  The AR15 JP Silent Capture Spring 2-15 (JPSCS2-15), is not compatible the Primary Weapons System (PWS) old style Enhanced Bolt Carrier (EBC).   This is because the back-bore, rear opening of the bolt carrier, is not large enough to allow the guide rod of the SCS to travel through it.  This is important because the EBC guide rod is stationary and has the BCG retracts in to the buffer tube during the firing cycle the guide rod penetrates the rear of the BCG.  The PWS EBC is easily identified by the larger rear bearing area and smaller diameter back bore.  As a side notice I remember when the SCS first came out it was also recommended not for use with the PWS Enhanced Buffer 416 Tube because the tube had a slight interior taper that did not allow the SCS to fully seat to the rear.  This is not currently listed in the product instructions.

  JP also makes an AR10 second generation version of the SCS, JP Silent Capture Spring 2-10 (JPSCS2-10).  The AR10 version is not recommended for use with HK MR762 due to its larger diameter buffer, nor the DPMS GII, which will not cycle with the SCS due to its carrier design.  It’s nice that a company cares enough about its products to let you know it’s limitations before you buy it.  

  The JP 9mm SCS will work with some 9mm pistol caliber carbines, but won’t work with others. A key to look for is if the 9mm bolt has an opening large enough and deep enough to the guide rod to penetrate.  With the numerous 9mm PCCs hitting the market I can see why it’s difficult for JP to specifically state which PCC it will work for and which ones it won’t.  But I can guarantee it will work in the JP GMR-15 9mm PCC.  (Hopefully I can review one of these in the future.)  Or if you are building your own JP sells an outstanding line of 9mm PCC products.

  Both the AR15 and AR10 are available in a heavy H2 version.  The heavy H2 is recommended for use with short barrel rifles, suppressors, select-fire, piston-operated systems and when manufacture recommends use of an H2.

  If you’re not sure what system to get JP has a SCS selection guide.

  The SCS is pricey, $139.00 to $196.00, depending on type: standard, H2, with assorted spring kit; AR15, AR10 or 9mm.  Price is the main thing that kept me away from buying the SCS.  While walking the prize table at the 2017 He-Man Nationals I picked up a gift certificate from JP Enterprise that allowed me to get two Silent Captured Springs and two Low Mass BCGs.  I ordered the AR15 SCS standard version with the assorted spring kit.  The set arrives in a neat triangular shaped box.   The kit includes the SCS system, five springs, spacer and steel weights.   You can also order additional tungsten or steel weights to customize the system for your AR15 application and ammunition.  The SCS is designed to be used in a carbine buffer tube.  If you have a rifle length buffer tube don’t worry.  JP includes a spacer to be used in a rifle length buffer tube.  Simply drop the spacer in the rifle length buffer tube first, then install the SCS next.  If you have an A5 buffer tube you should be able to trim it to fit.

  A note on carbine buffer tubes.  As I stated earlier, JP does a lot of research on their products before they release them.  They also listen to feed back from their customers.  Due to the different manufactures of buffers tubes not all of them may have the same exact internal dimensions.  As a result, the SCS was seating deeper in some tubes then necessary.  JP came up with a solution to the problem.  Place a quarter in the bottom of the buffer tube and it will fill the space needed.  There should be no gap between the back of the BCG and the buffer end of the SCS.

The standard version is designed to be a low-mass system.  The weight on the system is set by using steel or tungsten sleeves.  A standard buffer uses small steel cylinders. The H buffer comes with two steel sleeves and one tungsten sleeve.  Additional steel and tungsten sleeves can be purchased to fine tune your rifle

  The five springs are rated from light to heavy and are color coded.  You must refer to the product instructions to reference the colors (so keep the product instructions with your springs!)  Changing the springs is very easy. Remember safety – wear safety glasses! You are dealing with a spring under tension and parts may fly into your eyes. Depress the weight end and place a small Allen wrench or pin into the hole in the guide rod.  Unscrew the guide rod screw.  Now remember the weights are under spring tension and now there is nothing to keep them from flying off into the oblivion that your detent pin flew off to last month. Push the weights down to relieve tension on the Allen wrench, or pin, and remove it.  Slowly allow the spring to expand until there is no more pressure against the weights.  The weights should be clear of the guide rod, remove them and then you can remove the spring.  Select what spring you want to use, and install it in reverse order.  The guide rod screw comes a dap dried of 242 loc-tite on it and should be good for about two removals and resets.

  I used the white spring because my intended purpose was a light weight 3-gun rifle with a JP Low Mass BCG.  I also have JP Adjustable gas block on the rifle length gas system.  After tuning the gas system for reliability, I ran the rifle through a series of tests.  I used both JCAA 55 grain and 77 grain long range ammo.  The cycling was flawless and fast.  I also noticed the rifle recoil was smooth and shot very flat, it did not nose dive when it returned to battery.  I think this is because of the limited range of motion of the SCS.  The forward motion of the spring is stop by the retention screw in the guide rod.  In a standard AR15 the buffer is pushed forward by the spring and the buffer hits the detent pin in the lower receiver.  This may or may not be correct but either way, the system provides smooth cycling.

  So is the JP Silent Captured Spring worth the money?  I would say, “Yes.”  I did not find anything negative about the system and saw an advantage to it.  I would highly recommend it for any higher end build.  And I think everyone needs at least one high end build AR15.

  DISCLAIMER:  The products reviewed have been personally purchased or won as prizes from shooting competitions.  Any items provided to the writer for review shall be stated and disclosed in the review. The writer does not receive any financial compensation from any company’s in this review and will identify any sponsorship relationship with any companies in the review.





Self-contained, complete spring buffer system. Eliminates the drag and twang of traditional buffer springs.  


AR15 shooters looking to improve the performance of their rifle and end the twang.


  • Exceptionally smooth operation

  • Easy installation

  • Unique look

  • Adds in recoil efficiency

  • No bolt bounces


Available for all types of AR systems.

Easy to adjust buffer weights

Easy to adjust spring weights


One of those things I can’t imagine living without. – The Truth About Guns

It will blow your mind how smooth it makes your rifle. – The Firearm Blog


The Firearm Blog: Gadget Review

Tactical Gun Review – JP Rifles LMOS and Silent Captured Spring Review


MSRP:  $139.95-$206.95

Retail: $139.95-$169.95 @ Brownell's



JP Enterprises



  • Easy to install

  • Easy to adjust

  • Smooths weapons reciprocation

  • Quite


  • Expensive (but worth it)