AR 9 bolt doesn't catch

[Robin]

When I put this together I bought a heavy bolt catch with extension. Even before I bought it, from the picture, I couldn't see how this would work, and I was right, it doesn't.

In fact, with it in hand, I don't see how it could work even if the extension ddid reach the magazine.
There is no annex to the magazine like a standard AR.

What am I missing. I have searched the internet looking for an answer and after literally hours, I can find nothing.
Any help would be greatly appreciated.
Robin

 

[togmaster]

Glock Mag lowers don't have a LRBHO.

 

[Robin]

LRBHO
WUZZAT?
Robin

 

[BDinPutnam]

Glock Mag lowers don't have a LRBHO.

Some do, some dont. My QuarterCircle 10 does but it doesn't work all the time.

 

[BDinPutnam]

LRBHO
WUZZAT?
Robin

Last
Round
Bolt
Hold
Open

 

[togmaster]

LRBHO
WUZZAT?
Robin

Last round bolt hold open.

 

[togmaster]

Some do, some dont. My QuarterCircle 10 does but it doesn't work all the time.

That's why I built a colt pattern rifle. That and the fact I don't own a glock.

 

[Robin]

Hmmmmm, I did a lot of reading before I set out on that project, guess I missed that part. Seems like there should be an alternative to make the style I have work.
Robin

 

[meketrefe]

Glock Mag lowers don't have a LRBHO.

Bad design.

 

[Calculon]

My Matrixarms AR9 has LRBHO. Glock mags.

 

[garyv350]

I had 2 AR 9's that didn't have LRBHO. I got 2 of these. They work. Haven't had an issue with them.

Pistol Caliber Billet Upper

Manufacturer: New Frontier Armory Model: Pistol Caliber Billet AR-9 "Slick Side" Upper with LRBHO Caliber: Multi -THIS NOT A FIREARM -- NO FFL NEEDED -Dealer Price will appear in cart when logged in

www.newfrontierarmory.com

 

[ArmedCorgi]

When I put this together I bought a heavy bolt catch with extension. Even before I bought it, from the picture, I couldn't see how this would work, and I was right, it doesn't.
View attachment 71673
In fact, with it in hand, I don't see how it could work even if the extension ddid reach the magazine.
There is no annex to the magazine like a standard AR.
View attachment 71674
What am I missing. I have searched the internet looking for an answer and after literally hours, I can find nothing.
Any help would be greatly appreciated.
Robin

What lower do you have? Some have it, some don't. What I have learned with my AR9 build is that nothing is standard spec. I went through a whole ordeal with Foxtrot Mike because his bolt, which was advertised as working with any Glock lower, wouldn't work with my Glock lower.

 

[meketrefe]

My Matrixarms AR9 has LRBHO. Glock mags.

Like the way it should be since the mags have a push slot.

This lifter is a bit more complicated that what it needs to be but it explains how a cantilever should be an integral part of the receiver...

 

[ArmedCorgi]

Like the way it should be since the mags have a push slot.

This lifter is a bit more complicated that what it needs to be but it explains how a cantilever should be an integral part of the receiver...
View attachment 71718

That is how my AR9 lower is designed.

 

[meketrefe]

That is how my AR9 lower is designed.

The lifter doesn't have to be complicated but one needs to make the catch spring softer or then adjust the mags...

 

[ArmedCorgi]

The lifter doesn't have to be complicated but one needs to make the catch spring softer or then adjust the mags...

To be honest, the whole mechanism seems frail to me considering the weight and force of the bolt.

 

[BDinPutnam]

Like the way it should be since the mags have a push slot.

This lifter is a bit more complicated that what it needs to be but it explains how a cantilever should be an integral part of the receiver...
View attachment 71718

I believe the Angstadt design uses something similar.

 

[Celt]

I believe the Angstadt design uses something similar.

Ill have to open mine up, but when i tested a couple mags before listing it for sale it didnt work. Not sure if it requires adjusting or not, but i didnt care too much. I like that it runs glock mags, that was more important to me than a lrbho.

 

[BDinPutnam]

Ill have to open mine up, but when i tested a couple mags before listing it for sale it didnt work. Not sure if it requires adjusting or not, but i didnt care too much. I like that it runs glock mags, that was more important to me than a lrbho.

Often the ones that do need slight adjustments (downward) on the spring. When I was troubleshooting mine with QC10 they suggested clipping a couple coils off the end.

 

[Robin]

Interesting hold open design Mek and very similar to what I was designing in my head yesterday. It is amazing to me the amount of information you 'don't' get when you google around looking for information on this subject.
Is there a way to retrofit it what I have? If there is, I can't find it.
This project wasn't meant to be anything more than a fun gun that shoots readily accessible cheap ammo that has the removable magazine capacity. I achieved that and it is a fun gun to shoot and the ammo is cheap, but it would be even more funner if the bolt locked back on an empty magazine.
Robin

 

[ecosystem3]

or get a conversion adapter and run it on a standard lower. Works with Glock, Berreta or S&W mags. Has LRBHO too

STERN DEFENSE, LLC AR-15 9MM CONVERSION ADAPTER | Brownells

There's no need to go with a pistol-caliber specific AR lower on your next pistol-caliber carbine build. With the Stern Defense AR-15 9mm Conversion Adapter you have the ability to utilize popular pistol magazines which you may already have a supp...

www.brownells.com

 

[Robin]

Thanks eco, but I've already spent too much to get what I got! If I can't find something that will retro fit to what I have I'll just live with it and devote some spare time now and again to designing a mechanism that will do just that. I imagine there are thousands out there that would pay for such an item.
Robin

 

[repete]

Thanks eco, but I've already spent too much to get what I got! If I can't find something that will retro fit to what I have I'll just live with it and devote some spare time now and again to designing a mechanism that will do just that. I imagine there are thousands out there that would pay for such an item.
Robin

Or in a pinch you can count BANG 1 BANG 2 BANG 3 and so on.

 

[BDinPutnam]

@Robin not entirely on topic but I would be curious to know what upper you are running (or what barrel you used, either really). The only thing I didnt like about mine (without a vertical foregrip) is that the heavy machine gun steel barrel I had on it was very muzzle heavy. Been thinking of building a new one with a lighter barrel.

 

[togmaster]

@Robin not entirely on topic but I would be curious to know what upper you are running (or what barrel you used, either really). The only thing I didnt like about mine (without a vertical foregrip) is that the heavy machine gun steel barrel I had on it was very muzzle heavy. Been thinking of building a new one with a lighter barrel.

In an effort to help you derail the thread, here is the barrel I used. The weight feels fine to me.

Kaw Valley Precision AR-15 16'' 9MM 4150 QPQ AR-15 Barrel

Kaw Valley Precision AR-15 16' 9MM 4150 QPQ AR-15 Barrel

www.joeboboutfitters.com

 

[Robin]

BD, I don't remember the barrel Mfgr. its a very common one being used by many. It is heavy, heavier than I would have expected, but I don't have to hump it around all day so I'm good, makes for a very stable platform.
repete, I used to be a counter, got out of the habit but still find my self doing it sometimes.
Robin