Which Recoil System? JP SCS Gen 2 vs MBX PCC Buffer System

[littlefish]

On ‎7‎/‎20‎/‎2017 at 0:31 PM, Maxamundo said:

I liked 4 tungsten and a lighter spring like white or black.

For a couple matches I've been running two steel and two Tungsten with 100% AR15 spring (no color spring from 5 pack), with JP bolt and no wave washer. It works pretty good with my mouse fart 115gr load. Very good on steel challenge stages. Plan to try your wave washer setup at some point. Thanks for your input!    

[Aircooled6racer]

On July 26, 2017 at 2:17 AM, littlefish said:

For a couple matches I've been running two steel and two Tungsten with 100% AR15 spring (no color spring from 5 pack), with JP bolt and no wave washer. It works pretty good with my mouse fart 115gr load. Very good on steel challenge stages. Plan to try your wave washer setup at some point. Thanks for your input!    

Hello: Try the JP green or black spring and see how that works for you. They are only 1 pound apart from each other. Thanks, Eric

[10cup]

I run four tungsten weights with the H7 wave spring and white spring.  Works fantastic, no LRBHO in my GMR-15.  If you run the H5 wave spring the bolt will lock back  on last round.  I tried Eric's set up too and liked this one best.  Your result may be different based upon your ammo etc.

 

Edited July 29, 2017 by 10cup

[Aircooled6racer]

1 hour ago, 10cup said:

I run four tungsten weights with the H7 wave spring and white spring.  Works fantastic, no LRBHO in my GMR-15.  If you run the H5 wave spring the bolt will lock back  on last round.  I tried Eric's set up too and liked this one best.  Your result may be different based upon your ammo etc.

 

Hello: Maybe I will have to try this. Anyone have a spare H7 spring I can borrow? Thanks, Eric

[KzBoost]

5 hours ago, Aircooled6racer said:

Hello: Maybe I will have to try this. Anyone have a spare H7 spring I can borrow? Thanks, Eric

 

I have one coming that you can have. pay shipping and I'll send it as soon as I get it.

*edit... NVM I have an M7... not H7. Sorry.

Edited July 29, 2017 by KzBoost

[Aircooled6racer]

Hello: Looks like the CS100-M7 or CS100-M11 are the ones to use with the JP buffers? I want to try the heavy setup and see how that works for me. The stock JP buffer setup did not work that well for me causing too much flip and dip( sounds like a pancake place). Thanks, Eric

[Aircooled6racer]

Hello: So I tested all the JP springs that I have for there SCS 9mm buffers using the 223 springs. The stock 308 Red/Yellow spring is 15 1/2lbs, no paint 14 1/2lbs, Yellow 15lbs, green 13 1/2lbs, black 12 1/2lbs and the white is 11 1/2lbs. This should help some out when they decide on which spring they would like to try. The tungsten weights are 1.4815ozs and the steel are 0.6948ozs. I will have to weight the aluminum carrier with "O" rings and cir clip to see what the total will be. Thanks, Eric

[longbeard]

On 7/24/2017 at 0:59 PM, TRUBL said:

lighter recoil spring.

Everyone is sooooooo caught up with how much the muzzles rises, thats a bunch of crap......as long as the gun comes back to POA before you can double tap is key. And when I mean double tap, I mean sight once and double tap. I know for a fact that we are doing double taps on steel at 25 yards (6" square plates) with our barrels, recoil systems and 124's 

 

May not hit the second shot everytime.......but we are doing 80% and at distance......makes us very confident to double tap anything at 10yards for sure.

 

I concur.  Felt recoil doesnt mean anything.  You want the follow up shot to be quick and as close to the original POA as possible.  After playing with Tim's adjustable buffer and a 5.6 fixed buffer with rifle springs and .223 springs I have settled on a .223 spring with Tim's buffer dialed with as much preload as the reset will allow.  Using 3.6 grains of TG behind a 125RN I get two holes within 1/2 in. of each of other when I have a solid mount and double tap without looking.   At 3.4 grains the second shot is higher.  This tells me that you need the kinetic energy (snap) to get the return to POA.  The heavier buffer with a higher charge and more preload gets the bolt to transfer it's energy back to lowering the muzzle more quickly for the second shot.  Results can vary with how much shoulder you put into it, and I would think barrel weight.   I am using Tim's ULW barrel.  Also, The rifle spring from a physics standpoint makes more sense to return the dot quicker, but I like the feel of the .223 better and think it suits my stance for whatever reason.  

 

 

 

 

 

[nickbfishn]

Final update. I finally was able to run the gun after I got the smally spring installed on the bottom end of my JPSCS.

 

On the system I have 3 steel, 1 tungsten, 80% spring and the H-11 smally. All I can say is WOW. This thing shoots like a .22, and after my first 6 or 8 rounds I literally had to put the gun down for a minute because I was giggling like a school girl ?.

 

 The cycle is very short and very quick. I can double tap as quick as my limcat limited gun and hit an 8" plate at 25 yards with every round, no sweat. I had a couple of issues with feeding and ejecting, but only when I used ammo deemed as "practice." This is the ammo that for one reason or another didn't load properly and we put it into separate boxes. Well, I grabbed the wrong box when I left the house. I did, however, have about 30 good rounds and I didn't have any issues with it whatsoever.

 

on a final note, I had a box of precision delta reman FMJ ammo that I was using for my production gun and I decided to run a few rounds for shits. This ammo produces 133pf out of my pistol so it's obviously much hotter than my pcc ammo. However, it actually felt good to shoot and the dot barely moved, but the cycling was wicked fast and sounded a little harsh. I'm afraid to use it with this setup because I feel like it will beat the gun apart. Thoughts?

[Aircooled6racer]

Hello: That is good to get a report on the added spring. I guess I will phone tomorrow to order a couple to try. They sent me an email saying they no longer offer samples on the one I requested. I may also look at using stacked rubber and plastic washers or Bellville washers. Thanks, Eric

[nickbfishn]

8 minutes ago, Aircooled6racer said:

Hello: That is good to get a report on the added spring. I guess I will phone tomorrow to order a couple to try. They sent me an email saying they no longer offer samples on the one I requested. I may also look at using stacked rubber and plastic washers or Bellville washers. Thanks, Eric

I ordered a sample of the h10 & h11 and got both. The diff is the height. I was afraid the 11 would be to tall, but it actually works just like max had described. The bolt comes back under normal tension to maybe a half inch past trigger reset. If I pull real hard I can make it move about another 1/4". 

 

With the h10 it came back about 3/4-1" past reset under light tension and about another 1/4" under hard tension.

 

if you want to try the H10 I'll send it to you. 

[Aircooled6racer]

14 hours ago, nickbfishn said:

I ordered a sample of the h10 & h11 and got both. The diff is the height. I was afraid the 11 would be to tall, but it actually works just like max had described. The bolt comes back under normal tension to maybe a half inch past trigger reset. If I pull real hard I can make it move about another 1/4". 

 

With the h10 it came back about 3/4-1" past reset under light tension and about another 1/4" under hard tension.

 

if you want to try the H10 I'll send it to you. 

Hello: That would be great so I can do some testing with it. After I am done I can send it back to you. I have 3 JP 9mm buffers I am playing with right now and a couple of different upper setups. I loaned out one of my buffers to a guy with an SBR conversion and he likes the 3 steel, 1 tungsten with the green(90%)spring best so far. Thanks, Eric

[KzBoost]

Is it necessary to reapply loctite after taking apart the SCS? 

[Aircooled6racer]

23 minutes ago, KzBoost said:

Is it necessary to reapply loctite after taking apart the SCS? 

Hello: I just put a very small dot of blue on it. I have also not put any on it and it has not come loose over 600 rounds or so. Thanks, Eric

[Aircooled6racer]

Hello: I tried two different setups at the match this past weekend and it was a disaster. It seemed to have more recoil with lots of dot movement. I was also having feeding problems with the Colt mags giving me yard sales in the chamber. The setups I was using were white spring, 2 steel and 2 tungsten weights. The other was 2 tungsten, 1 aluminum and 1 steel with the black spring. I loaned out my other buffer setup and it shot great for him. That will teach me to try new things at a match without testing them before hand. Thanks, Eric

[1911luvr]

Hello: I tried two different setups at the match this past weekend and it was a disaster. It seemed to have more recoil with lots of dot movement. I was also having feeding problems with the Colt mags giving me yard sales in the chamber. The setups I was using were white spring, 2 steel and 2 tungsten weights. The other was 2 tungsten, 1 aluminum and 1 steel with the black spring. I loaned out my other buffer setup and it shot great for him. That will teach me to try new things at a match without testing them before hand. Thanks, Eric

 

I just built a PCC for my girlfriend and before I ordered an expensive buffer I figured I'd try some parts I already had. I used the buffer spring from my ATI 9mm and a 3oz buffer with my 115gr loads, and it shot so well I'm leaving it as is. Here's some video showing the lack of muzzle rise:

 

 

 

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[Tampa-XD45]

3 minutes ago, 1911luvr said:

 

I just built a PCC for my girlfriend and before I ordered an expensive buffer I figured I'd try some parts I already had. I used the buffer spring from my ATI 9mm and a 3oz buffer with my 115gr loads, and it shot so well I'm leaving it as is. Here's some video showing the lack of muzzle rise:

 

https://goo.gl/photos/SGXfw6zGswLqfdsm8

 

 

 

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The simpler the better.  I also run a standard carbine (3 oz) buffer and never have any problems from 115g to 147g.

[TRUBL]

1 hour ago, Aircooled6racer said:

Hello: I tried two different setups at the match this past weekend and it was a disaster. It seemed to have more recoil with lots of dot movement. I was also having feeding problems with the Colt mags giving me yard sales in the chamber. The setups I was using were white spring, 2 steel and 2 tungsten weights. The other was 2 tungsten, 1 aluminum and 1 steel with the black spring. I loaned out my other buffer setup and it shot great for him. That will teach me to try new things at a match without testing them before hand. Thanks, Eric

metalform strikes again??

[nickbfishn]

Eric, I had similar problems running my first match this weekend, but not with recoil and follow up shots. I think the buffer is fine...I think.

 

my problem is a feeding issue of some sort. The on every stage I had at least 2 times when I had to rack the bolt because the bullet wasn't fully chambered. And on all but 2 occasions the extractor didn't even have a hold of the case. On the 2 occasions that it did hold the case I was able to recover the rounds and see that there was an identical shaved section of the bullet cone. I'm using 147 flat nose  coated. 

 

So so yesterday I ramped the barrel extension and took it to the range today. Had similar results as the match, just not as frequent.

 

so I dedicated to mark the bullets and see where the damage was occurring. as it turns out its shaving the top side of the round, not the bottom where I was sure it was hitting the barrel extension. 

 

So my thought now is the round is hitting the bottom of the extension and then bouncing up and shaving on the top side of the extension and all this bouncing is causing the round to pull out of the extractor.

 

thoughts?

[Aircooled6racer]

Hello: Mine were ramping up but not going into battery. Kinda like on a 1911 when the case does not go under the extractor correctly. I do know it is a double or triple feed problem. I am not sure if it from the mag lips being too narrow or wide or not enough spring pressure. I have not tested it again yet since it has been raining here. One of my mags has the feed lips at 0.518" and the other is around 0.501". I am going to load up some other bullets at different lengths to see if that helps. The only thing I did change from the last match when it all worked great was the buffer setup so that tells me something, What, I am not sure yet. Thanks, Eric

[BigBamBoo]

3 hours ago, 1911luvr said:

 

I just built a PCC for my girlfriend and before I ordered an expensive buffer I figured I'd try some parts I already had. I used the buffer spring from my ATI 9mm and a 3oz buffer with my 115gr loads, and it shot so well I'm leaving it as is. Here's some video showing the lack of muzzle rise:

 

 

 

 

 

 

Hello.

 Please do not take this the wrong way, but you actually have quite a bit of muzzle movement going on. The "correct" buffer and spring combo can pretty much take that muzzle movement away.

 

I recently watched a video of my friend and i shooting a USPSA match and we have very simular carbines. The main difference is he was running a Heavy Buffers Q buffer and I am using a Taccom adjustable buffer with a JP .223 rifle spring. The difference between the to is quite notiable in the video. His recoils very simular to yours while mine is pretty much just flat.

 

 The video has been posted here before, but if you would like to look at it I can repost it.

 

take care

 

 

3 hours ago, 1911luvr said:

 

 

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[10cup]

44 minutes ago, nickbfishn said:

Eric, I had similar problems running my first match this weekend, but not with recoil and follow up shots. I think the buffer is fine...I think.

 

my problem is a feeding issue of some sort. The on every stage I had at least 2 times when I had to rack the bolt because the bullet wasn't fully chambered. And on all but 2 occasions the extractor didn't even have a hold of the case. On the 2 occasions that it did hold the case I was able to recover the rounds and see that there was an identical shaved section of the bullet cone. I'm using 147 flat nose  coated. 

 

So so yesterday I ramped the barrel extension and took it to the range today. Had similar results as the match, just not as frequent.

 

so I dedicated to mark the bullets and see where the damage was occurring. as it turns out its shaving the top side of the round, not the bottom where I was sure it was hitting the barrel extension. 

 

So my thought now is the round is hitting the bottom of the extension and then bouncing up and shaving on the top side of the extension and all this bouncing is causing the round to pull out of the extractor.

 

thoughts?

Just something I found in my testing on my GMR-15 that may help is the mag spring tension being too weak. Try stretching a little. Also like Eric mentioned, measure the feed lips of your mags and be sure they are wider at the front than the rear.  My Glock mags run great and the rear lip width is .347 while the front is .355

Just anFYI hope it helps. 

 

 

Edited August 7, 2017 by 10cup

[1911luvr]

 

Rearward movement is of little importance as it doesn't take me off target or cause me to lose the dot during doubles. My own PCC uses the JPSCS and the difference in performance isn't worth the hundred plus dollar premium over this.


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[BigBamBoo]

But yours has "muzzle flip" not just reward recoil. Again, I noticed this in my friends rig who was running the Q buffer vs my rig running the Taccom adjustable buffer. And I believe the tAccom is $75.00?

 

if it works for you, don't fix it. I was just commenting as you said you had no muzzle flip, but I noted there was. That was all.

[BlackBuzzard]

Not to drift the thread, but I find how I hold/grip the carbine has great effect on dot movement and recovery - shot to shot.

 

Lately I work on fast  pairs on steel at 24 yds, and Bill Drills on steel at a reasonably challenging distance......refining how I hold and trigger the PCC.