which comp for 9mm PCC ?

[Halo09]

On 1/19/2019 at 6:40 PM, MemphisMechanic said:

@NPDriver what are you running in your Guard’s bolt/buffer system? After 6 months of changing things once a month, I’ve gotten my 14.5” gun pretty much dead flat. Hammering 4 shots at 10yd puts them all about 2” apart.

 

Hydraulic 5oz buffer meant for a .308 carbine, JP 308 rifle spring, a wave spring and a short-stroking spacer in the back of the buffer tube.

 

Curious if you’ve done much tuning to the recoil system.

 

(Sure is jarring to go back to your buddies’ blowback guns though isn’t it? So much recoil.  )

 

what short-stroking spacer are you using?  I have a rifle length stock on mine, mostly due to preference and consistency between all my other comp rifles.  How big is the wave spring you are using?  

[NPDriver]

1 hour ago, Halo09 said:

Hey NPDriver, did you have to do anything to your mags or lower to get the CMMG bolt and work properly?  I had tried to build it up on my standard 9mm lower, but the bolt was hitting the back of the mags.  When I called CMMG, they said that I would have to move the mag catch on mags so they would sit lower, or file down my mag catch in the receiver to get it to the right height.  

It would run fine as long as I inserted the mag on an open bolt. It would scratch the hell out of the brass though. I pulled the mag catch out of my FM lower last week to mill the catch down a bit. I need a few things done at a machine shop at the moment. Finding the time to go is the problem. 

[Halo09]

1 minute ago, NPDriver said:

It would run fine as long as I inserted the mag on an open bolt. It would scratch the hell out of the brass though. I pulled the mag catch out of my FM lower last week to mill the catch down a bit. I need a few things done at a machine shop at the moment. Finding the time to go is the problem. 

I just broke down and ordered their lower at shot show.  The factory said to run carbine spring with carbine buffer, but I only had an A2 stock sitting around.  Tried my taccom buffer system with an A2 spacer, and it didn't cycle.  Switched to a rifle spring and rifle buffer and it's been humming along with 124's

 

[funkymonkey1111]

anyone have any experience with the CMMG SV Comp?  Was looking at their PCCs and wondering how it performed.

[MemphisMechanic]

On 2/12/2019 at 6:48 PM, Halo09 said:

what short-stroking spacer are you using?  I have a rifle length stock on mine, mostly due to preference and consistency between all my other comp rifles.  How big is the wave spring you are using?  

A stack of quarters. Works great, and see no reason to do anything otherwise.

[mellino19]

Hi all,

 

So I just got home from the range doing all kinds of silly tests with various ammo, uppers, comps, and recoil systems. I took video but need to edit and post to YouTube for  everyone to see. I figure I can give a brief run down here right now. 

 

I have two uppers: 

-14.5” Warsport with PWS pcc comp and a foxtrot mike bolt. 

-16” JP stainless with Venom DD comp and a JP stainless bolt.

 

I’m running a CMC 3.5lb PCC trigger. The first test I ran was with the Blitzkrieg 5007 hydraulic buffer and 308 rifle length spring.

The second test was with the new 5105HD hydraulic buffer AND the 2.6oz weight, also with 308 rifle   length spring. 

 

I used factory 115gr, 124gr,  and 147gr ammo. I also used 147gr reloads I typically run in both carry optics and PCC divisions. I choreographed everything through each upper for rough power factory numbers and they were as follows. Also note, I’m pretty sure there’s an error or two, I used the Dillon power factor calculator but may have forgotten to change the bullet weight. 

 

14.5” upper PF numbers:

115gr - 163

124gr - 173

147gr - 176

147gr reloads - 154

 

16” upper PF numbers:

115gr - 150

124gr - 158

147gr - 149

147gr reloads - 132 

 

I also tried some 124gr reloads at about 140-143pf that felt really good. 

 

Again, I think I screwed up the 14.5” upper numbers but they kind of make sense given burn rate with barrel length; I'm sure some velocity burns off after 14" or so.

 

I’ll get to the point, everything factory felt very hot and the comps didn’t seem to tame recoil a ton between different bullet weights; wait for the video to judge yourself. But once I ran the reloads through the 16” upper with the 5105HD and weight, holy hell is that a soft shooting gun! I was blown away the second I shot the first round. It was reliable for me although very soft, the rounds ejected within inches of the gun, they were actually all on the bench next to me instead of thrown on the ground further away or behind. 

 

It it feels like a paintball gun or a 22 with slightly more kick than normal. 

 

I think if if you ran the Blitzkrieg 5105HD with their 2.6oz weight and ammo in the 135-145 power factor range you’ll be very happy and won’t worry about how well a comp works. 

Edited February 18, 2019 by mellino19
grammer fixes

[dmshozer1]

5 minutes ago, mellino19 said:

Hi all,

 

So I just got home from the range doing all kinds of silly tests with various ammo, uppers, comps, and recoil systems. I took video but need to edit and post to YouTube for  everyone to see. I figure I can give a brief run down here right now now. 

 

I have two uppers: 

-14.5” Warspoirt with PWS pcc comp and a foxtrot mike bolt. 

-16” JP stainless with Venom DD comp and a JP stainless bolt

 

I’m running a CMC 3.5lb PCC trigger. The first test I ran was with the Blitzkreig 5007 hydraulic buffer and 308 rifle length spring. The second test was with the new 5105HD hydraulic buffer AND the 2.6oz weight, also with 308 rifle length spring. 

 

I used factory 115gr, 124gr,  and 147gr ammo. I also used 147gr reloads I typically run in both carry optics and PCC divisions. I chonographed everything through each upper for rough power factory numbers and they were as follows. Also note, I’m pretty sure there’s an error or two, I used the Dillon power factor calculator but may have forgotten to change the bullet weight. 

 

14.5” upper PF numbers:

115gr - 163

124gr - 173

147gr - 176

147gr reloads - 154

 

16” upper PF numbers:

115gr - 150

124gr - 158

147gr - 149

147gr reloads - 132 

 

I also tried some 124gr reloads at about 140-143pf that felt really good. 

 

Again, I think I screwed up the 14.5” upper numbers.

 

I’ll get to the point, everything factory felt very hot and the comps didn’t seem to tame recoil a ton between different weights, wait for the video to judge yourself. But once I ran the reloads through the 16” upper with the 5105HD and weight, holy hell is that a soft shooting gun! I was blown away the second I shot the first round. It was reliable for me although very soft, the rounds ejected within inches of the gun; they were actually all on the bench next to me instead of thrown on the ground further away or behind. 

 

It it feels like a paintball gun or a 22 with slightly more kick than normal. 

 

I think if if you ran the Blitzkrieg 5105HD with their 2.6oz weight and ammo in the 135-145 power factor range you’ll be very happy and won’t worry about how well a comp works. 

Amen!!!!!!!!!!!!!!

[mellino19]

Just an edit/information addition.

 

I used Winchester 115gr and 124gr ammo, the regular white box with all black writing, and I used Sig 147gr ammo.

 

If you don't reload and want minor power factor ammo for the same performance, look into Federal Syntech 147gr or even their new Syntech 135gr; it should give you very similar results as the reloads I'm shooting (147gr RN with 3.3g Titegroup).

[Bwillis]

I thought I was doing a good job cleaning my mbx comp until I purchased a new one. I noticed the dimension differences and started cleaning yesterday. I soaked it for 2 hours in the ultrasonic, placed it cleaning solution over night and chiseled 187.2 gr of lead out. I noticed maybe 3 matches ago my dot bounce was different now I know why. With my apa comp I took it on one trial outting shooting fmj. The top holes plugged within 500 rounds, lesson learned jhp from now on. 

[Silverscooby27]

Or TMJ. That’s what I shoot so I don’t have as many feeding issues with the flat nose.

[Bwillis]

27 minutes ago, Silverscooby27 said:

Or TMJ. That’s what I shoot so I don’t have as many feeding issues with the flat nose.

 

What company do you use for tmj? Everglades has a cmj Montana gold but it is priceyyyyyy!