My uncle has had a Colt Match H-Bar for like 20 years, never an issue. The only complaint he's ever had was how horrible the trigger was. I told him with ALL the options available today there's no way he should have a reason to keep complaining about the stock trigger. So he picked up and installed a Rise Armament Rave 140. (The reviews on them were pretty positive.) Dry fire function tested it after install, safety and reset works. During live fire it will fire the chambered round but won't fire the next. It ejects the spent case and chambers the next but will not fire again. He manually ejects the live round, loads it back into mag and manually chambers it again, same thing, fires that round, cycles and trigger is dead. He repeated this several times, it will not fire the second round. He pulled BCG and inspected everything and confirmed everything is the way it's supposed to be.

It will reset trigger while hand cycling but not live fire. He also tried two different trusted mags.

I asked him to do something out of the norm just out of curiosity. It's NOT safe practice and I'm sure some here will complain but it's not necessary. I asked him to do it again but not to manually eject the live round and VERY CAUTIOUSLY open the receiver to visually inspect whether the hammer is cocked or not. The hammer was in the fired position.

I know he needs to call the manufacturer and we tried but it was today (Friday) and five minutes after 5pm so they're probably closed till Monday.

Does anyone have a reasonable explanation as to what could be causing this?

My friend just built a AR and used a rise armament trigger. He had the same issue the disconnector wouldn’t release the hammer. He emailed Rise Armament and they emailed him a picture showing where he should use a file to remove some material on the hammer. After he did that he hasn’t had anymore problems.
Edit: found a picture, basically you just remove the sharp edge at the angle of the red line on the hammer in the pic. Just take a few swipes with a fine file or sharpening stone and test it out.

I'm not sure these would be same issue. My uncle's rifle's hammer appears to be riding the carrier back to the fired position when cycling during just live fire. It cocks and stays back when hand cycling.

Could you explain a bit more how these two issues are the same. Maybe I'm missing it.

Does your uncle know for sure the hammer is riding the bolt? Search Rise Armament trigger not resetting it appears to be pretty common. It makes the trigger feel dead.

Yea we're noticing these complaints now.

The hammer is in the fired position after the rifle cycles. Dead trigger.

Deleted

" />

The Rave 140 doesn't have set screws like many cassette type triggers, like their RA-140 SST, it has springs on the bottom to put opposing tension in the pins.

I did this once, forgot I had a large pin lower, gun wouldn't pass function test.  I bought an Elftmann large pin drop in for it.  Works very well.

It really helps when I wear my up close glasses for things.

They were the correct pin size.

It's on its was back to Rise.

I have two buddies that each bought a Rise trigger and had same issue as you.  They were put in newer lowers and it wasn't a pin size issue.  I stay away from Rise Armament.

I have two of these triggers. Not many rounds with either one but it's been good so far.

If I would have known ahead of time I wouldn't have bought them.

First post was clear that it passed function test but wouldn't reset.

Contacted Rise, sent back.

Update: He got a New replacement, installed today, it works now.

Getting ready to change into someone more comfortable. Name changes coming.

Don't know if the same problem exists with the newer RA as it did / does with the older 140. The metal housing / body of the assembly is not compatible with some AR makes; the DPMS Oracle is one and there are others. Naturally, they blame the gun. I had this issue with my Oracle. Any other assembly from "mil-spec" to other aftermarkets fit just fine. Removing a couple of millimeters of material from a particular spot on the front of the housing solved the issue. They've known of the problem forever. Wouldn't doubt it if the spec for the housing remained the same. There were actually 2 issues regarding the trigger in this linked thread. Hopefully I have linked to page 5. Scroll down a bit past the halfway mark and the issue I'm referring to will be apparent. Rise Armament Trigger Issue

It baffles me how some triggers require the disconnecter to be timed.

This is 2020.

The rifle was fully assembled during dry-fire function test.