Spikes 9mm Buffer Issues?

[NolansMindset]

Alright guys so I just finished up putting together a Spikes 9mm build and Im running into a small issue. With the buffer i'm using, it wont go back far enough to engage the bolt catch. Its VERY close but not enough.

Heres what i'm using:
KAK Buffer Tube
Spikes ST9X 9mm Buffer
Wolff XP Carbine Spring

Now i've actually messed around with a few different combos without any luck.

Ive tried:
ST9X with Wolff XP
ST9X with Standard Carbine Spring
Spikes T2 with carbine spring and Spikes Spacer
Spikes T2 with Wolfe XP spring and Spikes Spacer

The only combo that worked was a Spikes T2 without a spacer BUT the bolt travels too far back. It goes AT LEAST an inch past the bolt catch and I know if I run it that way it'll spear off the bolt catch in no time.

So since this i'm my first dive into a 9mm build I thought I would reach out to you guys to see if anyone has ran into this and if so, what worked for you.

Any and all help is greatly appreciated.

- Nolan -

 

[SouthernSlammed]

In trying to get it to maually lock, or last round bolt hold open?

 

[NolansMindset]

In trying to get it to maually lock, or last round bolt hold open?

Empty mag or manually pulling the bolt back doesn't work. It right on the edge but need a little more travel.

 

[SouthernSlammed]

@permaneo vox any hints?

 

[permaneo vox]

I'm running the KAK tube on my pistol as well. With a Colt pattern lower, it locks on the last round. It sounds like the bolt is longer than normal. I dont have my 9mm in front of me, but I'll check it tomorrow & see how far past the bolt stop, the bolt can travel. I can measure the bolt length too.

 

[NolansMindset]

That permaneo, I appreciate it!

 

[Leshaire]

The only combo that worked was a Spikes T2 without a spacer BUT the bolt travels too far back. It goes AT LEAST an inch past the bolt catch and I know if I run it that way it'll spear off the bolt catch in no time.

@chance and I were messing around with 9mm ARs the other night and one of their shop guns has a spacer that goes behind the spring I believe to help this. Theirs was breaking bolt catches before the spacer was inserted I believe. Maybe he can chime in.

 

[NolansMindset]

The only combo that worked was a Spikes T2 without a spacer BUT the bolt travels too far back. It goes AT LEAST an inch past the bolt catch and I know if I run it that way it'll spear off the bolt catch in no time.

@chance and I were messing around with 9mm ARs the other night and one of their shop guns has a spacer that goes behind the spring I believe to help this. Theirs was breaking bolt catches before the spacer was inserted I believe. Maybe he can chime in.

I’ve got one of the Spikes Tactical spacers they I tried with the T2 buffer and it came to about the same length at the ST9X and stopped just short of catching. I’m wondering if I need to trim the bumper on the buffer just a little. Has anyone tried that before?

 

[Hayata]

Trim the piece that is the cheapest to replace.

 

[Leshaire]

I’ve got one of the Spikes Tactical spacers they I tried with the T2 buffer and it came to about the same length at the ST9X and stopped just short of catching. I’m wondering if I need to trim the bumper on the buffer just a little. Has anyone tried that before?

What length barrel is on it and is it suppressed?

 

[TattooedGunner]

Man, I want a 9mm AR but it seems like they are a bitch to get them running right.

 

[Leshaire]

Man, I want a 9mm AR but it seems like they are a bitch to get them running right.

Mine ran like a top out of the box for 2 years before it started getting finnicky. In that time I prob put a few thousand rounds through it suppressed, and chopped the barrel down after about 500 of those. Then overnight it became a PITA lol

 

[NolansMindset]

Trim the piece that is the cheapest to replace.

I really think that’s what I’m going to try. I think KAK Industries sells replacements for like a $1 so if I screw it up it won’t be expensive, haha

 

[NolansMindset]

Trim the piece that is the cheapest to replace.

I’ve got one of the Spikes Tactical spacers they I tried with the T2 buffer and it came to about the same length at the ST9X and stopped just short of catching. I’m wondering if I need to trim the bumper on the buffer just a little. Has anyone tried that before?

What length barrel is on it and is it suppressed?

It’s an 8.3” Spikes Barrel and it will be unsuppressed

 

[Rwjeter]

@NolansMindset I’m running an AR10 spring and the KAK 9mm Extended Heavy buffer. It’s done well for me. It won’t travel too far back and shear your bolt catch, but it travels far enough for LRBHO on my Colt pattern build.

 

[NolansMindset]

@NolansMindset I’m running an AR10 spring and the KAK 9mm Extended Heavy buffer. It’s done well for me. It won’t travel too far back and shear your bolt catch, but it travels far enough for LRBHO on my Colt pattern build.

Off hand do you know how long the kak Buffer is? I was talking to Kurt from KAK last night and he said he thought they were right at 4”. The ST9X I’m using is over 4” (like 4.12 if I’m not mistaken) so if that’s the case that would probably give me the extra little bit I need.

 

[Rwjeter]

Off hand do you know how long the kak Buffer is? I was talking to Kurt from KAK last night and he said he thought they were right at 4”. The ST9X I’m using is over 4” (like 4.12 if I’m not mistaken) so if that’s the case that would probably give me the extra little bit I need.

Not off hand. I’ll check when I get home and post a picture for you.

 

[SouthernSlammed]

I'm running KAK spring with Spikes ST9X. Not having any issue with bolt catch. My first issue was trigger not resetting.

 

[Leshaire]

Thats weird. Come to think of it, my buffer was significantly longer than KGMade's. But maybe that spacer made up the exact difference. I can measure some things tonight if you need.

 

[chance]

Thats weird. Come to think of it, my buffer was significantly longer than KGMade's. But maybe that spacer made up the exact difference. I can measure some things tonight if you need.

Yea your buffer is 9mm specific and makes up for the difference in bolt length. Yours was the same as our buffer + spacer