Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide

Can light triggers cause doubling or bump fire?


tayronachan

Recommended Posts

I came across the following posts about doubling from ar15 dot com. I had this happen to me twice out of about 350 rds (new rifle, FTE issue seems to have worked it self out). I wasn't even sure the rifle had doubled the first time. Both times it happened in the prone position. And if I remember correctly, I had been using a light pull with just the tip of my finger on the trigger. It's really annoying, and embarrassing. LR-308 classic, 4 rail free float, two stage trigger came with the rifle as ordered.

 

"I have a new LR308 had it about 3 weeks now I installed a Jard trigger in it when I first got it did all the function tests it passed no problem take it to the range sighting in and then plinking a little and it starts double firingicon_smile_shock.gif not every time maybe once or twice in a mag but it is very annoying as I am trying to work up a good load and it doubles there goes that group!!" 

 

"...the DPMS LR-308 stock trigger is horrible, so I was looking to change it out. The guys at DPMS told me NOT to use Jard triggers in my LR-308. Didn't ask why."

 

I'm thinking I just need to follow through better and hold the trigger back before releasing?

 

Link to comment
Share on other sites

OP do you already have the Jard trigger?  Setup is everything, with it.

 

I had a 2lb Jard in my .308 AR - it's in another rifle now, only because I got the .308 SR Gold for the .308.  On a few occasions, when others shoot my .308, they would double it.  It came directly from trigger follow-through (or lack of follow-through).  It's such a short reset, that if you don't have proper follow-through (and weak-finger it), you'll allow it to reset immediately.  The reaction to recoil (rifle coming back forward), and the imperceptible trigger finger position (let off trigger pressure, but trigger finger almost in the firing position) will bump the trigger again.  Boom #2.

 

WIth proper trigger follow-through, this is never, never a problem.  I briefed everybody since that shot that rifle with that trigger, prior to them shooting it (once I saw what was happening).

Link to comment
Share on other sites

Just hold the trigger all the way to the rear when you shoot - that's what you're looking for, for trigger follow-through.  You can't check Natural Point Of Aim without trigger follow-through, so that's one way to keep it in your head.

 

Your trigger finger should still be holding the trigger to the rear, after the rifle recovers from recoil and settles again...

Link to comment
Share on other sites

  • 6 months later...

Update; LR-308 Classic, free-float tube and a 2 stage trigger.

 

When I first got the rifle you could clearly feel the second stage, and you could tell when the trigger was going to break. Later the second stage disappeared, and you couldn't feel it break at all any more. The trigger was just a very, VERY light trigger, and no second stage at all, no "break". I think that is why it doubled.

 

I called DPMS and they said to just pull the trigger out, and send it in and they'd replace it. 3 weeks later I recieved the new trigger and installed it. I can clearly feel it break now.

 

I'll report back after I test it at the range.

Link to comment
Share on other sites

Update; LR-308 Classic, free-float tube and a 2 stage trigger.

 

When I first got the rifle you could clearly feel the second stage, and you could tell when the trigger was going to break. Later the second stage disappeared, and you couldn't feel it break at all any more. The trigger was just a very, VERY light trigger, and no second stage at all, no "break". I think that is why it doubled.

 

I called DPMS and they said to just pull the trigger out, and send it in and they'd replace it. 3 weeks later I recieved the new trigger and installed it. I can clearly feel it break now.

 

I'll report back after I test it at the range.

 

In the past, several people have reported this exact same condition with RRA 2-stage triggers - second stage goes soft, and essentially disappears, rendering the trigger an "expensive single stage" trigger.  I don't know if this is still happening with RRA 2-stage triggers or not.

 

Was this a DPMS-sourced trigger in a complete rifle?  Where did the trigger come from?

Link to comment
Share on other sites

In the past, several people have reported this exact same condition with RRA 2-stage triggers - second stage goes soft, and essentially disappears, rendering the trigger an "expensive single stage" trigger.  I don't know if this is still happening with RRA 2-stage triggers or not.

 

Was this a DPMS-sourced trigger in a complete rifle?  Where did the trigger come from?

The rifle is from DPMS complete. I've installed the new trigger from DPMS. About a two and a half week turn around, not bad at all. I've tested it at the range, and all is good.

 

Another issue had developed about the same time the second stage disappeared. It bothered me even more than the second stage going out. After firing, the bolt would chamber a new round but the trigger wouldn't reset. That would happen about 3 to 4 times every 20rds. At first I thought the round wasn't going fully into battery (all factory ammo), but the forward assit would not move the bolt forward at all. I think somehow the hammer rode the bolt forward to end up resting on the firing pin without firing the round, and the trigger is not reset. HA! Riddle me that!!  :D

Link to comment
Share on other sites

Another issue had developed about the same time the second stage disappeared. It bothered me even more than the second stage going out. After firing, the bolt would chamber a new round but the trigger wouldn't reset. That would happen about 3 to 4 times every 20rds. At first I thought the round wasn't going fully into battery (all factory ammo), but the forward assit would not move the bolt forward at all. I think somehow the hammer rode the bolt forward to end up resting on the firing pin without firing the round, and the trigger is not reset. HA! Riddle me that!!   :D

 

Disconnector not holding the hammer back .

Link to comment
Share on other sites

  • 1 month later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...