My LRBHO is not working ?? of the time

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[ARCHIVED THREAD] - My LRBHO is not working ?? of the time

Posted: 4/20/2017 3:43:55 PM EDT

Hello gang,

I have a ST Glock forged lower together with a Sprinco red spring, KVP 7.5 buffer and a BA 5.5" barrel. Today I went out to test it out with a hole bunch of different 9mm rounds I had lying around. The LRBHO only worked 40% of the times and mostly with ETS 33rd mags. I also used Magpul and factory Glock mags to test it out. Could the Spinco red buffer spring be the cause of the LRBHO not working ?? of the time? Should I try it out with an extra power Wolff, enhaced JP or blue Sprinco? Any help would be appreciated.

Thanks

Posted: 4/20/2017 5:36:10 PM EDT

[#1]

ST Glock lower?

Posted: 4/20/2017 5:37:24 PM EDT

[#2]

Yep

Posted: 4/20/2017 5:39:39 PM EDT

[#3]

When you manually cycle the bolt with an empty mag inserted, other than the ETS 33rd mag, will it lock back?

What upper receiver are you using? Another forum member mentioned how it could depend on the upper and how much material is on the inside edge where the LRBHO bar is at on these lowers. He said one of his uppers works with it, while another he has does not.

Posted: 4/20/2017 6:17:30 PM EDT

[#4]

Quote History

Quoted:
Yep

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Wasn't aware "Spikes Tactical" was making 9mm Glock lowers. You may need to adjust the bolt hold open bar.

Posted: 4/20/2017 6:21:29 PM EDT

[#5]

Quote History

Quoted:
When you manually cycle the bolt with an empty mag inserted, other than the ETS 33rd mag, will it lock back?

View Quote

It locks back on all my mags when i do it manually.

Posted: 4/20/2017 6:23:18 PM EDT

[#6]

Quote History

Quoted:
What upper receiver are you using? Another forum member mentioned how it could depend on the upper and how much material is on the inside edge where the LRBHO bar is at on these lowers. He said one of his uppers works with it, while another he has does not.

View Quote

I'm using a ST slick side upper with a KVP bcg.

Posted: 4/20/2017 7:42:10 PM EDT

[#7]

Are the Spikes upper and lower advertised as being LRBHO?

Posted: 4/20/2017 9:38:19 PM EDT

[#8]

I just built a PSA LRBHO that everyone says looks like the ST. I put a good coat of oil on and in the LRBHO mechanism and worked it by hand before firing. I could feel it loosened up significantly when hand cycling. Shot 450 rounds, it failed on one mag, and that was towards the end of the day.

Posted: 4/20/2017 9:53:55 PM EDT

[#9]

Quote History

Quoted:
Are the Spikes upper and lower advertised as being LRBHO?

View Quote

The lower is LRBHO and the upper is a standard AR15 upper with no forward assist or deflector.

Posted: 4/20/2017 9:55:49 PM EDT

[#10]

Quote History

Quoted:
I just built a PSA LRBHO that everyone says looks like the ST. I put a good coat of oil on and in the LRBHO mechanism and worked it by hand before firing. I could feel it loosened up significantly when hand cycling. Shot 450 rounds, it failed on one mag, and that was towards the end of the day.

View Quote

What buffer?spring combo do you have on it? My setup ran great with FMJs, it was the LRBHO that didn't work all the time.

Posted: 4/20/2017 10:28:52 PM EDT

[#11]

Quote History

Quoted:

The lower is LRBHO and the upper is a standard AR15 upper with no forward assist or deflector.

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I could be wrong as I'm just now building a PCC, but it's my understanding that both the lower and the upper may need to be set up specifically for LRBHO for it to work consistently.

Posted: 4/20/2017 10:35:49 PM EDT

[#12]

Quote History

Quoted:

I could be wrong as I'm just now building a PCC, but it's my understanding that both the lower and the upper may need to be set up specifically for LRBHO for it to work consistently.

View Quote

I don't believe so, either the top or the bottom needs to be LRBHO. I don't think it will work with both having that feature.

Posted: 4/20/2017 10:45:26 PM EDT

[#13]

Quote History

Quoted:

I could be wrong as I'm just now building a PCC, but it's my understanding that both the lower and the upper may need to be set up specifically for LRBHO for it to work consistently.

View Quote

I believe only NFA style lowers and the first generation of PSA lowers needed an upper for it.

[ARCHIVED THREAD] - My LRBHO is not working ?? of the time

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