JP 9mm bolt and silent spring buffer

[utahjeepr]

Would like to hear opinions on the JP 9mm bolt and silent spring buffer system. I recently picked up a QC 10 colt mag pistol for a really good price. It came with the JP bolt and buffer. It runs great, but the buffer system requires removing the RE to remove the buffer for cleaning as it will not clear the Geissele trigger. Not a big deal, but kind of a PITA especially once I get the stamp and make it an SBR.

Also, wondering if it will perform well with a can, or if I will be better off running a different bolt and/or buffer. Got a smoking deal on it, less so if I have to swap bolts. I had planned to build exactly the same gun but with a "standard" 9mm bolt and buffer.

[jimmyheadgear]

I'm using the JP bolt and SCS in my QC10 Glock build. I needed to change out the spring because it was short stroking with 147 grain subs. After the swap out it runs smooth and quiet suppressed or unsuppressed.

[utahjeepr]

Thanks for the reply. If you don't mind, what are the specs on the required spring. Sourced from JP? So far mine runs great, but I only have 500 rounds through it so far. Mostly 115g all unsuppressed, no can yet.

I'm guessing the scs system is not very common among those on the board.

[jimmyheadgear]

Thanks for the reply. If you don't mind, what are the specs on the required spring. Sourced from JP? So far mine runs great, but I only have 500 rounds through it so far. Mostly 115g all unsuppressed, no can yet.

I'm guessing the scs system is not very common among those on the board.

The spring you'll want to start with is the lightest and work your way up, if you're trying to tune the gun. The springs that JP uses in their 9MM SCS are the 308 springs not the AR15 springs. Found that out the expensive way. They manufacture them with the strongest spring they offer.

Be aware that the bolt will probably not lock open after the last round. That seems to be normal with QC10 even though they keep trying to improve it.

[utahjeepr]

308 springs, copy that. Good to know, thanks.

Heard about the LRBHO issue with Glock mags. That was my deciding factor between the Colt or Glock mag variants. So far bolt locks back 100% with the Colt mags.

Thanks again for the info.