Diagnosing a malfunction

[Matalpa]

I bought a Remington R-15 a few months ago to use for coyote hunting. I have probably put 150 rounds through it so far- mostly factory, and probably 30 handloads.

Today I was shooting at the range, using a front rest and rear sandbag. I was shooting my own handloads, with one in the chamber and 2 in a 10 round magazine. The trigger pull on this rifle is kind of long and heavy, and as I was shooting for group I was squeezing very slowly and carefully.

When the rifle fired, it sent 2 rounds downrange like it was a full-auto. It reminded me of a shotgun doubling- something I have experienced once and would not prefer to do again. It happened much faster than I could ever pull the trigger for aimed shots.

When I removed the remaining round from the chamber there was a very tiny dimple in the primer.

I fired the remaining round, with another in the same magazine using the same trigger pull- it operated normally this time.

A few notes- I am a pretty experienced handloader and have never had problems like this before, but my experience is mostly with bolt rifles.

I have a Dillon case gage- all cases were in spec.

Primers were Winchester small rifle.

So, did I have a slamfire or was there enough movement of the rifle during recoil that I basically pulled the trigger twice incredibly fast? Or something else?

Thanks for any input.

Matalpa

 

[elfster1234]

Re: Diagnosing a malfunction

As you were using some reloads...


I could be wrong on this and please correct me if i'm wrong, BUT it is very possible you had a slam fire on the 2nd round from the primer not being seating just under flush... THIS IS A HUGE PROBLEM! I always do a table top test on seated primers and make sure they are seated just below flush ESPECIALLY WITH SEMI-AUTO'S!!!!.... You're lucky the brass didn't explode and most likely ignited just as it was chambered.

 

[Temp9]

Re: Diagnosing a malfunction

It's hard to know exactly what's wrong without handling the rifle. My guess is a faulty or improperly installed trigger group. I'm not sure what trigger the R15 uses, but if it's the traditional style AR trigger, make sure the disconnector spring is installed large side down.

It's possible that you doubled due to recoil, but if the trigger pull is as heavy as you say, that isn't likely. Make sure you are following through properly and pinning the trigger to the rear after the shot breaks.

I don't think this is a reloading problem or a slamfire. Did you check the cartridge that doubled for a primer strike? In my (limited) experience, the slam fire potential of AR's is a bit overplayed. A primer that isn't seated deep enough will not have the anvil set properly, making it fairly difficult to ignite, even with a full on firing pin strike, much less the bolt face. That's not to say it can't happen, though, which is why it would be good to check the primer on the potentially faulty round.

 

[Redmanss]

Re: Diagnosing a malfunction

The small dimple in the primer is typical of an AR with the floating firing pin, and likely is not the cause. Elfster may be onto something if your primers are not seated properly, but is that's not the case, then look to your trigger. With a stock trigger I doubt you did a double pull, but that's still a possibility, especially if you don't have proper follow through.

Here's what you do with your trigger control in your follow through. Continue squeezing back on the trigger for at least a full second after your shot fires. When you release the trigger, you will have a "thunk" type sound as it resets. If you're not hearing that sound, you're not doing it right and you're releasing the trigger too fast. With the multiple recoil pulses felt in firing an AR, it is possible that you did a double squeeze and I've seen it happen before, but it is rare.

You can also do a function check on your rifle's trigger group as that can be the source of your problem, but as new as it is I doubt that is the case. With a cleared and empty rifle, dry fire one time and hold back on the trigger. Charge the rifle to reset the hammer while still holding back on the trigger, then release the trigger. Again, you should hear the "thunk". Do this several times to see if you can induce the hammer falling without a new trigger squeeze. If the hammer does fall, then you have a sear problem that will require replacement. If it doesn't fall, then look to your primers and your trigger finger itself.

 

[Eznutz]

Re: Diagnosing a malfunction

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Redmanss</div><div class="ubbcode-body">The small dimple in the primer is typical of an AR with the floating firing pin, and likely is not the cause. Elfster may be onto something if your primers are not seated properly, but is that's not the case, then look to your trigger. With a stock trigger I doubt you did a double pull, but that's still a possibility, especially if you don't have proper follow through.

<span style="color: #FF6666">Here's what you do with your trigger control in your follow through. Continue squeezing back on the trigger for at least a full second after your shot fires. When you release the trigger, you will have a "thunk" type sound as it resets</span>. <span style="color: #FF0000">If you're not hearing that sound, you're not doing it right and you're releasing the trigger too fast.</span> With the multiple recoil pulses felt in firing an AR, it is possible that you did a double squeeze and I've seen it happen before, but it is rare.
</div></div>

Its not a slam fire its called bump firing. pretty common if you are gingerly squeezing and not commiting to pull. You can still be slow and consistent but make sure you have commited to the pull and like mentioned above finish the movement to prevent the second disharge from occuring.

 

[Matalpa]

Re: Diagnosing a malfunction

Thanks for the quick replies.

The brass went in to a catcher that had lots of other brass in it, so I could not identify the 2 in the mishap.

I am pretty certain of primer seating was not an issue. I still use an old Lee hand primer seater that gives lots of "feel" when seating primers. There have been a few times something did not feel right while seating and they were very obvious, and I check each primed piece of brass as I put it down.

I tried dryfiring and holding the trigger back and going through those machinations- could not get gun to act up. I have been thinking about a Geisselle trigger- maybe now is the time.

Thanks for the help.

Matalpa

 

[elfster1234]

Re: Diagnosing a malfunction

is possible if you have a really light trigger pull... very possible. bump fire.


<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Eznutz</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Redmanss</div><div class="ubbcode-body">The small dimple in the primer is typical of an AR with the floating firing pin, and likely is not the cause. Elfster may be onto something if your primers are not seated properly, but is that's not the case, then look to your trigger. With a stock trigger I doubt you did a double pull, but that's still a possibility, especially if you don't have proper follow through.

<span style="color: #FF6666">Here's what you do with your trigger control in your follow through. Continue squeezing back on the trigger for at least a full second after your shot fires. When you release the trigger, you will have a "thunk" type sound as it resets</span>. <span style="color: #FF0000">If you're not hearing that sound, you're not doing it right and you're releasing the trigger too fast.</span> With the multiple recoil pulses felt in firing an AR, it is possible that you did a double squeeze and I've seen it happen before, but it is rare.
</div></div>

Its not a slam fire its called bump firing. pretty common if you are gingerly squeezing and not commiting to pull. You can still be slow and consistent but make sure you have commited to the pull and like mentioned above finish the movement to prevent the second disharge from occuring. </div></div>

 

[ringer706]

Re: Diagnosing a malfunction

Have you checked all the engagement points for the disconnector, hammer and trigger? From the sounds of it, it's a new or newer rifle so excessive wear on these surfaces would be minimal, but it is probably worth checking out. Also, do you lubricate your FCG? Excessive lubrication could also be the cause either by allowing the engagements to slip, or carbon fouling mixing with lubricant causing the disconnector to stick.

Best of luck!

 

[B3dlam]

Re: Diagnosing a malfunction

IF it was a slam fire you would likely see the primer have a reverse dimple. I wouldnt expect a slam fire to be the case the only slam fire I have ever had was when I made the mistake of manually pushing a round into the chamber then letting the bolt slam home. The firing pin slammed forward striking the primer but as there was no hammer holding it forward the primer flowed into the firing pin hole as it ignited showing a reverse dimple.

In the case of your rifle I would guess that it wasnt caused by an improperly assembled rifle as it has only done this once in around 150 rounds.

Definitely ensure you are following through on the trigger properly holding it completly to the rear until the recoil impulse is complete. You should hear your sear reset when you let the trigger out.

If you find anything please sure I am curious to hear what you find.

 

[ringer706]

Re: Diagnosing a malfunction

OP, have you been able to isolate the problem?

 

[Matalpa]

Re: Diagnosing a malfunction

Well, I looked at all the brass and all the primers looked the same, so I feel pretty good about eliminating the slam fire. I tried to make it malfunction as redmanss suggested and it worked correctly. So, I will go to the range this weekend and see what happens, but I suspect the bump fire.

For any of you guys that have had or seen a bump fire- were the shots incredibly close together? As in, I don't think I could pull the trigger that fast on purpose and I don't think the other guys noticed the second shot.

Thanks for the info everyone.

Matalpa

 

[callen3615]

Re: Diagnosing a malfunction

I have seen new shooters do this on ar pattern rifles. actually saw a friend do it with 22lr!


If you dont continue to push the trigger to the rear after it breaks you can effectively bump fire.


Think about it, if your reset is VERY close to the point in which the sear releases the hammer you would have a 2 round burst trigger. If you ever install an adjustable trigger you have to test for this. Dry fire, hold the trigger to the rear, cycle the bolt, slowly release the trigger to the reset, if you dont set up the trigger correctly you can sometimes fire just before the trigger resets, or would reset.

Anyway, if you have a standard milspec style trigger you shouldnt have that problem.


I think your finger just barely reached the point where the hammer fell and your finger stayed their after the reset and the momentum of the gun being pushed back at your finger by your shoulder fired the 2nd round. Id put money on it.


I know that its hard to shoot a stock ar15 trigger for accuracy. You want to slowly apply pressure until it breaks, but its not a crisp bolt action trigger. Kinda like how 1911s and double action revolvers are different, you cant hold a double action revolver on target and slowly apply 2lbs of pressure on the trigger like you can a 1911. You gotta get that thing on target and push to the rear, keep it moving, dont let it stop.

If this is a dedicated target gun I would suggest putting a match trigger in it. RRA, JP, I frankly think Geiselle or Jewel is kind of a waste but theyre all alot better than a stock AR trigger.

 

[Eznutz]

Re: Diagnosing a malfunction

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Matalpa</div><div class="ubbcode-body">Well, I looked at all the brass and all the primers looked the same, so I feel pretty good about eliminating the slam fire. I tried to make it malfunction as redmanss suggested and it worked correctly. So, I will go to the range this weekend and see what happens, but I suspect the bump fire.

For any of you guys that have had or seen a bump fire- were the shots incredibly close together? As in, I don't think I could pull the trigger that fast on purpose and I don't think the other guys noticed the second shot.

Thanks for the info everyone.

Matalpa </div></div>

Yup.. myself! It sounds like a machine gun.....and it turns your groupings to shit. I was like you a bolt guy mostly so precision AR shooting takes like i said a little more commitment to the trigger pull. I had a Timney in my AR and thought it was the trigger, so i switched it with a geisselle and the same thing happened. So i started practicing a more distinct follow through on my shots and that solved the problem. I never did it with a standard 8#/or factory trigger, only on lighter triggers is when i had the problem. so it wasn't the equipment, just the operator. let us know how your next range trip turns out. And for what its worth I love my Geiselle. smooth as butter and breaks like glass.