PSA AR-9 - Anyone switch out the buffer and spring yet?

[uod]

I was wondering if anyone has changed out the buffer and spring on an otherwise stock Palmetto State Armory AR-9. I was thinking about going with one of the Blitzkrieg Components 9mm AR-15 Hydraulic Buffer & Spring Combos, but I'd hate to spend the money if it doesn't make much of a difference.

[photoracer]

I am using one of their barrels but opted to use the MVB 9mm collapsible stock and its custom buffer and dual spring combo on my project. I wanted a short stock and this seems to be the way to go.

[aandabooks]

What is the issue with the stock setup? I'm not real tuned into the AR15/9 stuff yet and what changing certain items do for you.

[uod]

The stock setup has what seems to be a very heavy spring and buffer combo. The gun jumps a lot more than one of the JP AR-9s does --- and, I am wondering how much of this has to do with the buffer/spring combo that PSA includes.

[P.E. Kelley]

I swapped out the heavy (black) buffer and carbine spring for a standard (223) rifle length buffer and spring.

I think it feels better...

[StealthyBlagga]

I recently tested the VLTOR A5H4 buffer (full disclosure: they sent it free for evaluation), It works in any standard carbine buffer tube with an A2 spring. It is heavier than a regular 9mm buffer, and longer so it limits bolt travel. I expected the shorter travel to make recoil feel harsher, which it does, but it also speeds up shot-to-shot times noticeably. I did a semi-scientific test which I will be writing up when I have some time. I would highly recommend it as an inexpensive drop-in alternative to the standard setup if you are doing a new build.

If you already have a 9mm buffer system in a CAR buffer tube, then adding a simple spacer behind it will get you a lot of the improvement that I saw with the VLTOR A5H4 buffer. To check if there is already a spacer behind the buffer spring, pull the bolt back all the way until it impacts the rear of the buffer tube, press in the bottom of the bolt catch, then ease the bolt forwards again and see how much travel you have before the bolt hits the bolt catch. If more than maybe 1/4", then you probably have no spacer behind the buffer. You can buy a spacer for less than $10 from New Frontier Armory, but you can test the concept even cheaper - put between $2 and $2.75 worth of quarters in the back of your buffer tube behind the spring - adjust until you can just lock the bolt back with the bolt catch. If this works to your liking, you can leave them there or buy the NF part.

Edited June 16, 2016 by StealthyBlagga

[Nightops]

I put 5 or 6 quarters under my PSA buffer before even firing firing since I had heard about 9mm guns breaking the bolt catch without a spacer. Probably close to 1k rounds through it so far. I don't get what people are talking about with harsh recoil in these.

[M8Stealth]

In my QC10 build with pistol buffer tube, I'm running a Primary Weapons Systems 9mm suppressor buffer, KAK pistol buffer spring and 12 quarters (actually measured BCG length, compressed spring length to derive proper quarter stack).

Soft like a .22