Hello, I'm new to the forum and new to AR-15's. I decided to put one together recently. I bought a complete RRA standard lower, and put a 16" flat top upper on it. First day at the range, everything was going well, and then about 80 rounds into shooting the new rifle it fired a 5 round burst with one trigger pull. It happened two more times while slow firing the rifle. I have no clue what would cause this. All parts are AR-15 semi-auto. RRA semi-auto BCG. Any ideas?
Gunsmithing AR-15 burst firing? Need Advice!
- Thread starter GRP7099
- Start date
Re: AR-15 burst firing? Need Advice!
I have had that before and may have nothing to do with what yours is doing but...the pin for the trigger group had worked its ways out a little bit and was allowing the rifle to go burst and if I held the rigger a certain way it would empty a magazine. Might want to check out your pins and if you find them a little loose think about anti-walk pins.
I have had that before and may have nothing to do with what yours is doing but...the pin for the trigger group had worked its ways out a little bit and was allowing the rifle to go burst and if I held the rigger a certain way it would empty a magazine. Might want to check out your pins and if you find them a little loose think about anti-walk pins.
Re: AR-15 burst firing? Need Advice!
did you wind up with an extry spring? it goes under the sear.
did you wind up with an extry spring? it goes under the sear.
Re: AR-15 burst firing? Need Advice!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mar2012</div><div class="ubbcode-body">did you wind up with an extry spring? it goes under the sear. </div></div>
I think that you mean the disconnector.
ETA: To test your rifle for proper function do this:
1. MAKE SURE YOUR RIFLE IS UNLOADED
2. REPEAT STEP 1
3. With rifle off safety, press and hold trigger, this will drop the hammer.
4. While still holding the trigger, rack charging handle rearward. This will reset the hammer.
5. Release the trigger and you should hear a click if the disconnector is operating propperly. This click is the sound of the disconnector releasing the hammer to contact the trigger.
6. Pull the trigger again and the hammer should drop.
This should tell you if the disconnector is doing its job. You could also do this with the upper off the lower and just manipulate the hammer with your opposite hand.
Hope this makes sense.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mar2012</div><div class="ubbcode-body">did you wind up with an extry spring? it goes under the sear. </div></div>
I think that you mean the disconnector.
ETA: To test your rifle for proper function do this:
1. MAKE SURE YOUR RIFLE IS UNLOADED
2. REPEAT STEP 1
3. With rifle off safety, press and hold trigger, this will drop the hammer.
4. While still holding the trigger, rack charging handle rearward. This will reset the hammer.
5. Release the trigger and you should hear a click if the disconnector is operating propperly. This click is the sound of the disconnector releasing the hammer to contact the trigger.
6. Pull the trigger again and the hammer should drop.
This should tell you if the disconnector is doing its job. You could also do this with the upper off the lower and just manipulate the hammer with your opposite hand.
Hope this makes sense.
Re: AR-15 burst firing? Need Advice!
Replace the trigger/hammer group. That one is shot. Get a Giessele Automatics, the $175 one.
Replace the trigger/hammer group. That one is shot. Get a Giessele Automatics, the $175 one.
Re: AR-15 burst firing? Need Advice!
don't get caught with it, w/o proper BATFE permit or you WILL get busted.
don't get caught with it, w/o proper BATFE permit or you WILL get busted.
Re: AR-15 burst firing? Need Advice!
What CS said. It's most likely the sear, probably worn out.
What CS said. It's most likely the sear, probably worn out.
Re: AR-15 burst firing? Need Advice!
What kind of ammo were you shooting?
Check for the spring under the disconnector. Do the function check mentioned above. Make sure the tip of the hook on the disconnector is not broke or chipped as well as the opposing hook on the hammer. If you want to send me pics I can tell you if they are good or not.
What kind of ammo were you shooting?
Check for the spring under the disconnector. Do the function check mentioned above. Make sure the tip of the hook on the disconnector is not broke or chipped as well as the opposing hook on the hammer. If you want to send me pics I can tell you if they are good or not.
Re: AR-15 burst firing? Need Advice!
It sounds to me like disconnect not working properly. What kind of Fire Control parts did you get? If they were true RRA, then something is not installed correctly. If they were gun show "bargains" just as good as Colt...pitch the whole lot. (before you blow up your weapon and/or get busted)
I doubt it is the sear, although I did have a customer several years ago bring in a AR parts gun he had built from gun show parts and the Hammer sear notch was not formed correctly, like it was a bad shot in the mold. One that should have been destroyed..but that is what makes gun show bargains, just that a bargain!
Double check your assembly of the fire control components.
It sounds to me like disconnect not working properly. What kind of Fire Control parts did you get? If they were true RRA, then something is not installed correctly. If they were gun show "bargains" just as good as Colt...pitch the whole lot. (before you blow up your weapon and/or get busted)
I doubt it is the sear, although I did have a customer several years ago bring in a AR parts gun he had built from gun show parts and the Hammer sear notch was not formed correctly, like it was a bad shot in the mold. One that should have been destroyed..but that is what makes gun show bargains, just that a bargain!
Double check your assembly of the fire control components.
Re: AR-15 burst firing? Need Advice!
I'm colt certified. When a non nfa ar type rifle doubles/triples, etc its a couple of things that become suspect.
Diconnectors on mil spec parts are made from 8620 steel. When carberized its hard as a whores heart.
If the heat treat is wrong they'll run for awhile. Its a high load/wear part. They'll last awhile and then what your experiencing happens.
My advise. Buy mil spec parts and have them fitted by a smith with AR experience.
2nd. As mentioned if a pin wiggles out it can do it too.
Last:
You technically own a machine gun now. Don't take this lightly. ATF defines it as two or more shots fired with a single trigger pull. As dumb as this sounds, a malfunctioning double barrel shotgun also falls into this catagory.
Last. The "auto sear" in a m4 is a timing device. It ensured the bolt is in battery before the primer strike. Your rifle doesn't have this so its only a split second away from a potentially bad accident.
Don't play around. Get it fixed asap. Don't take it to the range till you know its right.
Good luck
C.
I'm colt certified. When a non nfa ar type rifle doubles/triples, etc its a couple of things that become suspect.
Diconnectors on mil spec parts are made from 8620 steel. When carberized its hard as a whores heart.
If the heat treat is wrong they'll run for awhile. Its a high load/wear part. They'll last awhile and then what your experiencing happens.
My advise. Buy mil spec parts and have them fitted by a smith with AR experience.
2nd. As mentioned if a pin wiggles out it can do it too.
Last:
You technically own a machine gun now. Don't take this lightly. ATF defines it as two or more shots fired with a single trigger pull. As dumb as this sounds, a malfunctioning double barrel shotgun also falls into this catagory.
Last. The "auto sear" in a m4 is a timing device. It ensured the bolt is in battery before the primer strike. Your rifle doesn't have this so its only a split second away from a potentially bad accident.
Don't play around. Get it fixed asap. Don't take it to the range till you know its right.
Good luck
C.
Re: AR-15 burst firing? Need Advice!
Trash it. Bone stock AR triggers are junk anyway.
Trash it. Bone stock AR triggers are junk anyway.
Re: AR-15 burst firing? Need Advice!
I am also Colt certified. Sounds like you have springs mixed up or installed incorrectly and or missing. Depending on the LPK you have some are Chinese junk! with parts that are even close to spec.
1)Under the disconnector there is a somewhat conical spring if installed with the large end up the spring will bind in the trigger and disconnector will not function giving your current result.
2) If you do not have the conical spring in the trigger and have a straight coiled spring you have a missing or miss-located spring.
3) If you have a hammer/trigger pin walking out of the lower the hammer spring is installed incorrectly. legs of the hammer spring should be on top of the trigger spring.
Please heed the notice as given in the above posts You Have a <span style="color: #FF0000">Full Auto Weapon</span> and this needs to be addressed.
If you cannot determine the cause please take it to a competent gunsmith.
I am also Colt certified. Sounds like you have springs mixed up or installed incorrectly and or missing. Depending on the LPK you have some are Chinese junk! with parts that are even close to spec.
1)Under the disconnector there is a somewhat conical spring if installed with the large end up the spring will bind in the trigger and disconnector will not function giving your current result.
2) If you do not have the conical spring in the trigger and have a straight coiled spring you have a missing or miss-located spring.
3) If you have a hammer/trigger pin walking out of the lower the hammer spring is installed incorrectly. legs of the hammer spring should be on top of the trigger spring.
Please heed the notice as given in the above posts You Have a <span style="color: #FF0000">Full Auto Weapon</span> and this needs to be addressed.
If you cannot determine the cause please take it to a competent gunsmith.
Re: AR-15 burst firing? Need Advice!
From the sound of the post, it's not a parts kit build, just a complete upper and lower purchased separately.
What ammo were you shooting?
From the sound of the post, it's not a parts kit build, just a complete upper and lower purchased separately.
What ammo were you shooting?
Re: AR-15 burst firing? Need Advice!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GRP7099</div><div class="ubbcode-body">Hello, I'm new to the forum and new to AR-15's. I decided to put one together recently. I bought a complete RRA standard lower, and put a 16" flat top upper on it. First day at the range, everything was going well, and then about 80 rounds into shooting the new rifle it fired a 5 round burst with one trigger pull. <span style="color: #FF0000">It happened two more times while slow firing the rifle. </span>I have no clue what would cause this. All parts are AR-15 semi-auto. RRA semi-auto BCG. Any ideas? </div></div>
If I read the highlighted section above correctly, it only happened while slow firing? If so, you may be "bump" firing. Basically your finger stays in the same place but the recoil from the first (and subsequent rounds until your finger is moved) and recovery activate the trigger. If this is the case you are only getting one round fired with each "pull" of the trigger and not in possession of a machine gun.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GRP7099</div><div class="ubbcode-body">Hello, I'm new to the forum and new to AR-15's. I decided to put one together recently. I bought a complete RRA standard lower, and put a 16" flat top upper on it. First day at the range, everything was going well, and then about 80 rounds into shooting the new rifle it fired a 5 round burst with one trigger pull. <span style="color: #FF0000">It happened two more times while slow firing the rifle. </span>I have no clue what would cause this. All parts are AR-15 semi-auto. RRA semi-auto BCG. Any ideas? </div></div>
If I read the highlighted section above correctly, it only happened while slow firing? If so, you may be "bump" firing. Basically your finger stays in the same place but the recoil from the first (and subsequent rounds until your finger is moved) and recovery activate the trigger. If this is the case you are only getting one round fired with each "pull" of the trigger and not in possession of a machine gun.
Re: AR-15 burst firing? Need Advice!
I'm not an AR expert, but, could a stuck firing pin cause this problem?
I'm not an AR expert, but, could a stuck firing pin cause this problem?
Re: AR-15 burst firing? Need Advice!
The cam action of the carier-bolt retracts the protrusion of the firing pin. Sounds like springs or a bad disconnector letting it bump fire vey easy.
The cam action of the carier-bolt retracts the protrusion of the firing pin. Sounds like springs or a bad disconnector letting it bump fire vey easy.
Re: AR-15 burst firing? Need Advice!
Bueller. Bueller...............
Bueller. Bueller...............
Re: AR-15 burst firing? Need Advice!
yes guys i meant disconnecter spring not sear spring sorry wrong nomenclature but it would cause this issue, or so ive heard,lol.
yes guys i meant disconnecter spring not sear spring sorry wrong nomenclature but it would cause this issue, or so ive heard,lol.
Re: AR-15 burst firing? Need Advice!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C. Dixon</div><div class="ubbcode-body">I'm colt certified. When a non nfa ar type rifle doubles/triples, etc its a couple of things that become suspect.
Diconnectors on mil spec parts are made from 8620 steel. When carberized its hard as a whores heart.
If the heat treat is wrong they'll run for awhile. Its a high load/wear part. They'll last awhile and then what your experiencing happens.
My advise. Buy mil spec parts and have them fitted by a smith with AR experience.
2nd. As mentioned if a pin wiggles out it can do it too.
Last:
You technically own a machine gun now. Don't take this lightly. ATF defines it as two or more shots fired with a single trigger pull. As dumb as this sounds, a malfunctioning double barrel shotgun also falls into this catagory.
Last. The "auto sear" in a m4 is a timing device. It ensured the bolt is in battery before the primer strike. Your rifle doesn't have this so its only a split second away from a potentially bad accident.
Don't play around. Get it fixed asap. Don't take it to the range till you know its right.
Good luck
C.</div></div>
Interesting,...seen several imported SPIKES TACTICAL .22 that do exactly what the man has with his AR platform.
Told Spikes,..they could not care less.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C. Dixon</div><div class="ubbcode-body">I'm colt certified. When a non nfa ar type rifle doubles/triples, etc its a couple of things that become suspect.
Diconnectors on mil spec parts are made from 8620 steel. When carberized its hard as a whores heart.
If the heat treat is wrong they'll run for awhile. Its a high load/wear part. They'll last awhile and then what your experiencing happens.
My advise. Buy mil spec parts and have them fitted by a smith with AR experience.
2nd. As mentioned if a pin wiggles out it can do it too.
Last:
You technically own a machine gun now. Don't take this lightly. ATF defines it as two or more shots fired with a single trigger pull. As dumb as this sounds, a malfunctioning double barrel shotgun also falls into this catagory.
Last. The "auto sear" in a m4 is a timing device. It ensured the bolt is in battery before the primer strike. Your rifle doesn't have this so its only a split second away from a potentially bad accident.
Don't play around. Get it fixed asap. Don't take it to the range till you know its right.
Good luck
C.</div></div>
Interesting,...seen several imported SPIKES TACTICAL .22 that do exactly what the man has with his AR platform.
Told Spikes,..they could not care less.
Re: AR-15 burst firing? Need Advice!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GRP7099</div><div class="ubbcode-body"> I bought a complete RRA standard lower,...... </div></div>
Pretty easy fix here.... call RRA. If the lower was complete and assembled by them, let them spend thier money, time, and effort making it right.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GRP7099</div><div class="ubbcode-body"> I bought a complete RRA standard lower,...... </div></div>
Pretty easy fix here.... call RRA. If the lower was complete and assembled by them, let them spend thier money, time, and effort making it right.
Re: AR-15 burst firing? Need Advice!
No matter what is the cause I would say you need to talk to RRA and let them fix it. Parts do go bad.
No matter what is the cause I would say you need to talk to RRA and let them fix it. Parts do go bad.
Re: AR-15 burst firing? Need Advice!
I'll bet all or part of the disconnector spur broke off of the hammer. I had that happen on one of their triggers and it did the same thing.
Whatever you do don't shoot it anymore. It could be construed that you are in possession of an illegally modified weapon.
Get a good AR smith to look it over or have RRA issue a call tag and come pick it up.
I'll bet all or part of the disconnector spur broke off of the hammer. I had that happen on one of their triggers and it did the same thing.
Whatever you do don't shoot it anymore. It could be construed that you are in possession of an illegally modified weapon.
Get a good AR smith to look it over or have RRA issue a call tag and come pick it up.
Re: AR-15 burst firing? Need Advice!
I've been told that swapping the bolt hold open spring with the disconnector spring can cause this.
The two springs appear very similar, and the conical spring CAN be forced into the spring pocket for the bolt hold open.
The instance of this I was told about acted this way:
Pulling the trigger would properly release the hammer. Keeping the trigger held back while recocking the hammer showed the disconnector working properly. If the trigger was released quickly, the disconnector would properly make the hammer "handoff" to the sear. However, if you tried to "reset" the trigger very, very gently, rather than the disconnector handing the hammer off to the sear, the hammer would simply drop.
I was told that while actually firing the rifle, it was impossible to NOT let the rifle run full auto.
As already mentioned, besides the felony you have currently avoided being charged with, you've got an out of battery discharge accident waiting/trying to happen. M16s and M4s have a mechanical "timing" system that assures the bolt is in battery before releasing the hammer. Your felony rifle does not have this.
I'm don't want you to feel like we're being hard on you - its just that we don't want to see a fellow enthusiast find themselves in trouble.
I've been told that swapping the bolt hold open spring with the disconnector spring can cause this.
The two springs appear very similar, and the conical spring CAN be forced into the spring pocket for the bolt hold open.
The instance of this I was told about acted this way:
Pulling the trigger would properly release the hammer. Keeping the trigger held back while recocking the hammer showed the disconnector working properly. If the trigger was released quickly, the disconnector would properly make the hammer "handoff" to the sear. However, if you tried to "reset" the trigger very, very gently, rather than the disconnector handing the hammer off to the sear, the hammer would simply drop.
I was told that while actually firing the rifle, it was impossible to NOT let the rifle run full auto.
As already mentioned, besides the felony you have currently avoided being charged with, you've got an out of battery discharge accident waiting/trying to happen. M16s and M4s have a mechanical "timing" system that assures the bolt is in battery before releasing the hammer. Your felony rifle does not have this.
I'm don't want you to feel like we're being hard on you - its just that we don't want to see a fellow enthusiast find themselves in trouble.
Re: AR-15 burst firing? Need Advice!
Just send it back to rock river and have them fix it. DO NOT TAKE IT BACK TO THE RANGE UNTIL FIXED.
Just send it back to rock river and have them fix it. DO NOT TAKE IT BACK TO THE RANGE UNTIL FIXED.
Re: AR-15 burst firing? Need Advice!
I'd had people come in with lowers that they had built running away on them and more often than not the bolt catch detent spring had been installed under the diconnector instead of the proper tapered disconnector spring. Even if you bought it assembled, it might be a good idea to check those springs.
ETA, I should have read all of the posts instead of repeating what Turbo had posted
I'd had people come in with lowers that they had built running away on them and more often than not the bolt catch detent spring had been installed under the diconnector instead of the proper tapered disconnector spring. Even if you bought it assembled, it might be a good idea to check those springs.
ETA, I should have read all of the posts instead of repeating what Turbo had posted
Re: AR-15 burst firing? Need Advice!
having tested many fire control groups including the rra unit, they are light on disconnector surface area. the disconnector being off isn't uncommon and is almost always the reason one of those particular fire control groups doubles, triples, or more.
if you need another 'stock' mil spec group just to test it agains i literally have a five gallon bucket of them. i'd gladly send you one if you need it to see if the problem is relieved upon replacement.
hope this helps.
-michael
having tested many fire control groups including the rra unit, they are light on disconnector surface area. the disconnector being off isn't uncommon and is almost always the reason one of those particular fire control groups doubles, triples, or more.
if you need another 'stock' mil spec group just to test it agains i literally have a five gallon bucket of them. i'd gladly send you one if you need it to see if the problem is relieved upon replacement.
hope this helps.
-michael
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