possible causes of double fires

croc4 · March 6, 2010, 07:59 PM

Hey guys,

I'm looking for all the possible causes of an AR15 double firing, the obvious one is the trigger groups disconector, but are there any other causes?

Thanks,

Croc4

10-96 · March 6, 2010, 08:03 PM

Could be a number of things. Do you reload or shoot reloads? Are the primers high? Also, is the firing pin bent, mushroomed, out of spec? And, the firing pin channel in the bolt could be fouled and not letting the pin rebound fully. Just a thought or two.

DnPRK · March 6, 2010, 11:02 PM

Some people who don't have a proper follow through when they pull the trigger on an AR-15 can fire two shots in rapid succession. The first shot when they pull the trigger and a second shot when they pull the trigger again as the rifle rebounds from recoil against their shoulder. There is nothing wrong with the rifle, just too light a touch on the trigger.

Some people make a game of firing multiple shots in rapid succession. Google "bump firing".

hoghunting · March 7, 2010, 12:05 AM

Factory trigger or aftermarket adjustable trigger? If it's an aftermarket, the sear engagement might need adjusting.

croc4 · March 7, 2010, 12:53 PM

its a 6.8spc shooting reloads, its an after market jard trigger, went through the instructions again yesterday, seems to per their instructions. I also noticed with only the bolt head and the firing pin, that the firing pin tends to stick in the bolt head depending on where the pin is rotated, some times it will drop out other times it seems to stick enough that it won't drop out when the the bolt head is facing up, so this could be the problem. The firing pin should always drop out when you face the bolt head up correct?

croc4

SwampYankee · March 7, 2010, 01:32 PM

What primers are you using? Type and manufacturer?

croc4 · March 7, 2010, 02:01 PM

small rifle, CCI-400

10-96 · March 7, 2010, 02:16 PM

Quote:

The firing pin should always drop out when you face the bolt head up correct?

That is correct. Now, it's a matter of finding out if the hole is burred or the pin is out of spec. Either you can get a powerful flashlight or laser and shine it through the bolt onto a piece of paper (kind of like a sun eclipse thing) to see if there are any irregularities. Or, see if you can borrow or obtain a very fine jewelers round file and smooth it out. Or, buy an additional firing pin- I think they should all be the same. However, I think there are some high-end pins like titanium, etc that might cost a bit more.

Either way, that is an issue that needs a fixing ruther than just hoping it'll go away. I started to recommend putting the pin in a bare bolt and tapping it on a hard surface until it acts right, but I would be affraid fouling would put you back where you started.

waterfowler · March 7, 2010, 02:35 PM

Is your firing pin seized and wont move? The pin could be bent or mushroomed or anything.

croc4 · March 9, 2010, 11:53 PM

thanks for all the suggestions guys, I worked on the bolt head and firing pin, light filing of the bolt head internal hole and then a polish of the firing pin and channel, etc. The stickyness is now gone, so I'm hopeful the issue is resolved.

Thanks again

Croc4

riverwalker76 · March 10, 2010, 12:57 AM

Quote:

small rifle, CCI-400

That's one of your problems!

I have a buddy who had problems with the CCI-400 series slam firing on him. After a little research we found out the way to go is CCI-450 Small MAg Rifle Primers. CCI-400 are designed for the small rifle caliber bolt guns, and the 450s have thicker cups. If you really want to tune her up get some CCI 41 primers. These are OEM CCI MILSPEC primers. They come in a white and black box with CCI 41 on them. This is what the military manufacturers use on military contract ammo. It's a heavy cup and won't slam fire.

March 6, 2010, 07:59 PM	#1
croc4 Senior Member Join Date: March 9, 2006 Location: Idaho Posts: 191	possible causes of double fires Hey guys, I'm looking for all the possible causes of an AR15 double firing, the obvious one is the trigger groups disconector, but are there any other causes? Thanks, Croc4 Last edited by croc4; March 6, 2010 at 08:12 PM.

March 6, 2010, 08:03 PM	#2
10-96 Senior Member Join Date: October 19, 2005 Location: Tx Panhandle Territory Posts: 4,159	Could be a number of things. Do you reload or shoot reloads? Are the primers high? Also, is the firing pin bent, mushroomed, out of spec? And, the firing pin channel in the bolt could be fouled and not letting the pin rebound fully. Just a thought or two. __________________ Rednecks... Keeping the woods critter-free since March 2, 1836. (TX Independence Day) I suspect a thing or two... because I've seen a thing or two.

March 7, 2010, 02:35 PM	#9
waterfowler Senior Member Join Date: January 31, 2010 Posts: 115	Is your firing pin seized and wont move? The pin could be bent or mushroomed or anything. __________________ If guns are outlawed, only the outlaws will have guns

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March 6, 2010, 11:02 PM	#3
DnPRK Senior Member Join Date: August 24, 2001 Location: LC, Ca Posts: 1,917	Some people who don't have a proper follow through when they pull the trigger on an AR-15 can fire two shots in rapid succession. The first shot when they pull the trigger and a second shot when they pull the trigger again as the rifle rebounds from recoil against their shoulder. There is nothing wrong with the rifle, just too light a touch on the trigger. Some people make a game of firing multiple shots in rapid succession. Google "bump firing".

March 7, 2010, 12:05 AM	#4
hoghunting Senior Member Join Date: March 27, 2006 Posts: 1,559	Factory trigger or aftermarket adjustable trigger? If it's an aftermarket, the sear engagement might need adjusting.

March 7, 2010, 12:53 PM	#5
croc4 Senior Member Join Date: March 9, 2006 Location: Idaho Posts: 191	its a 6.8spc shooting reloads, its an after market jard trigger, went through the instructions again yesterday, seems to per their instructions. I also noticed with only the bolt head and the firing pin, that the firing pin tends to stick in the bolt head depending on where the pin is rotated, some times it will drop out other times it seems to stick enough that it won't drop out when the the bolt head is facing up, so this could be the problem. The firing pin should always drop out when you face the bolt head up correct? croc4

March 7, 2010, 01:32 PM	#6
SwampYankee Registration in progress Join Date: November 1, 2008 Location: I can be found on a number of other forums. Posts: 1,333	What primers are you using? Type and manufacturer?

March 7, 2010, 02:01 PM	#7
croc4 Senior Member Join Date: March 9, 2006 Location: Idaho Posts: 191	small rifle, CCI-400

March 9, 2010, 11:53 PM	#10
croc4 Senior Member Join Date: March 9, 2006 Location: Idaho Posts: 191	thanks for all the suggestions guys, I worked on the bolt head and firing pin, light filing of the bolt head internal hole and then a polish of the firing pin and channel, etc. The stickyness is now gone, so I'm hopeful the issue is resolved. Thanks again Croc4