Light Primer Strike with JP and Armaspec Buffers but No Issues with Milspec

[AznTactical]

10.5" .300 blackout AR suppressed. Having light primer strike and bolt bounce issues.
-Armaspec Stealth Buffer G1 H1: 90% light primer strikes.
-Armaspec Stealth Buffer G2 H1: 50%+ light primer strikes.
-JP Captured buffer standard: 40% light primer strikes.
-Milspec spring and milspec carbine buffer: 0% light primer strikes, works great, no issues.
-Have also tried Geissele SSAE and Timney triggers too.

Helping a friend diagnose issues and am now lost. Checked headspace with go no-go and all good. When suppressed brass is being thrown around 2 o'clock. Unsuppressed, brass is being thrown about 4 o'clock. Up for any advice here on light primer strikes.

 

[USK308]

10.5" .300 blackout AR suppressed. Having light primer strike and bolt bounce issues.
-Armaspec Stealth Buffer G1 H1: 90% light primer strikes.
-Armaspec Stealth Buffer G2 H1: 50%+ light primer strikes.
-JP Captured buffer standard: 40% light primer strikes.
-Milspec spring and milspec carbine buffer: 0% light primer strikes, works great.
-Have also tried Geissele SSAE and Timney triggers too.

Helping a friend diagnose issues and am now lost. Checked headspace with go no-go and all good. When suppressed brass is being thrown around 2 o'clock. Unsuppressed, brass is being thrown about 4 o'clock. Up for any advice here on light primer strikes.

If you’re running suppressed, you need the H2 buffer.

Does the gun have an adjustable gas block or regular gas block?

 

[alamo5000]

It seems like it is over gassed with a can on it. Try an H2 or H3.

 

[AznTactical]

If you’re running suppressed, you need the H2 buffer.

Does the gun have an adjustable gas block or regular gas block?

adjustable Superlative.

 

[alamo5000]

How does the buffer affect the the primer strike?

The carrier is moving way too fast. It can bounce or any number of other things that will interfere with proper functionality.

Heavier Buffer slows down the system.

 

[AznTactical]

How does the buffer affect the the primer strike?

Speed or bolt bounce. I'm hoping buffer selection isn't hiding underlying issues.

 

[AznTactical]

The carrier is moving way too fast. It can bounce or any number of other things that will interfere with proper functionality.

Heavier Buffer slows down the system.

What is odd about bolt bounce is there is almost zero bolt bounce with the milspec buffer and buffer spring. He recorded a slo-mo vid for me when releasing the bolt using bolt catch lever.

 

[cas6969]

Not the same thing.

 

[USK308]

How does the buffer affect the the primer strike?
Does the bolt not go fully into battery?

If the buffer weight isn't sufficient relative to the gas pushing the buffer weight back, the buffer will not have enough kinetic energy to properly hit the BCG causing a proper primer strike by the firing pin.

 

[DHDeal]

Just so you know, depending on the generation, you can buy just the weight from Armaspec. I had a similar issue and bought different weights. I went to the carbine weight with my particular issue as the H1 was too heavy. I have a box with spare weights and springs so I know which works and which does not.

To be honest, if it weren't for how much I like how the whole package cycles I would say the all-in-one spring/buffers is a waste of money. Whoops, did I just admit I wasted a lot of money? Nope, that couldn't have been what I just admitted to.....

 

[AznTactical]

10.5" .300 blackout AR suppressed. Having light primer strike and bolt bounce issues.
-Armaspec Stealth Buffer G1 H1: 90% light primer strikes.
-Armaspec Stealth Buffer G2 H1: 50%+ light primer strikes.
-JP Captured buffer standard: 40% light primer strikes.
-Milspec spring and milspec carbine buffer: 0% light primer strikes, works great, no issues.
-Have also tried Geissele SSAE and Timney triggers too.

Helping a friend diagnose issues and am now lost. Checked headspace with go no-go and all good. When suppressed brass is being thrown around 2 o'clock. Unsuppressed, brass is being thrown about 4 o'clock. Up for any advice here on light primer strikes.

Update: My friend's AR is finally working 100% once he dumped the Armaspecs and JP and bought a BCM H2 and Sprinco spring (white).

Bad news: Now my AR is acting just like his (our AR's are almost identical). We put his lower on my upper with his new BCM H2 and Sprinco and 100% function. Maybe I need to dump my Armaspecs too.

 

[mtrmn]

Yeah just dump all the gucci crap. KISS principle.
Seems like almost every "My AR is screwed up" thread is using some kind of high dollar light weight reciprocating mass.
The above statements are my JMO and worth every penny you paid for it. YMMV

 

[mtrmn]

Yeah just dump all the gucci crap. KISS principle.
Seems like almost every "My AR is screwed up" thread is using some kind of high dollar light weight reciprocating mass.
The above statements are my JMO and worth every penny you paid for it. YMMV

Allow me to give a bit more explanation. As far as I can tell most of these type setups are geared towards special purpose guns using only 1 or 2 types of ammo. The tuning on these systems is very sensitive and you can't just pick up any ammo and expect it to be reliable.
If you build your gun from the get go with these parts, you will most likely run into a very long learning process to get it running. Then if you change ammo once it's running you'll have to start the process over again.
I have found that initially building the gun with pretty much proven basic parts is much more reliable and versatile. THEN if you want to incorporate the high end specialty items you can add and troubleshoot them one at a time. Then if you find they are too limited to a single type of ammo for your tastes, throw the basic parts back in and go.

 

[AznTactical]

Allow me to give a bit more explanation. As far as I can tell most of these type setups are geared towards special purpose guns using only 1 or 2 types of ammo. The tuning on these systems is very sensitive and you can't just pick up any ammo and expect it to be reliable.
If you build your gun from the get go with these parts, you will most likely run into a very long learning process to get it running. Then if you change ammo once it's running you'll have to start the process over again.
I have found that initially building the gun with pretty much proven basic parts is much more reliable and versatile. THEN if you want to incorporate the high end specialty items you can add and troubleshoot them one at a time. Then if you find they are too limited to a single type of ammo for your tastes, throw the basic parts back in and go.

You are correct. I only use 2 loads and they are 110 Barnes TACTX for my supers and 220 Noslers for my subs. I think I found my problem last night and it is a bent 1st stage spring on my Armaspec. I will confirm this afternoon when I hit the range with another Armaspec Stealth H that I am using in my 6 ARC that has no damage.
After digging around more info I found 2 other guys that has had the same problem. Common theme is they all have pistol gas system .300 blackouts too.

 

[mtrmn]

Yeah that does look problematic

 

[crosseyedshooter]

Are you able to see that you have proper preload on the rear of the BCG?

Basically, as you close the upper down onto the lower with the BCG in battery, the rear of the BCG should make contact with the buffer and push against it. I know the JP spring comes with a shim in case the SCS is too short to have proper preload.

 

[AznTactical]

Are you able to see that you have proper preload on the rear of the BCG?

Basically, as you close the upper down onto the lower with the BCG in battery, the rear of the BCG should make contact with the buffer and push against it. I know the JP spring comes with a shim in case the SCS is too short to have proper preload.

I have no detent spring in so there's always some contact between front face of buffer and rear face of carrier. I took the same type of Armaspec from a different AR and my black works fine. It's a buffer issue.