PDA

View Full Version : Primer strike no bang



woody
01-29-09, 04:05
DocGKR-

You posted something on this topic (TAP ammo failing to fire) on another forum. I read that with great interest. I was just wondering if you had heard anything further regarding additional occurrences, or any info at all. This has created quite a stir with my tactical team members.

It goes without saying, but anyone who may have some good information on this topic is more than welcome to jump in.

All assistance is greatly appreciated.

Maybe it was covered here too and I just missed it.

-Woody

DocGKR
01-29-09, 11:52
It was indeed posted before (https://www.m4carbine.net/showthread.php?t=25219), but is worth repeating

This past fall, a large SWAT team here had a failure to fire from an M4 with Hornady TAP ammo during an entry--fortunately no officers were hurt and the suspect immediately threw down his weapon when the carbine went click instead of bang. After the incident was concluded, the team went to the range and expended the rest of their carbine ammo and had one additional failure to fire. This same team had 3 Hornady TAP rounds fail to fire in training a couple of years ago. Last year, when Pat Rogers was teaching a class at a nearby agency, there were 5 failures to fire using Hornady TAP ammo. In all 10 cases, there appeared to be good primer strikes, but no rounds fired. On analysis, the ammunition had powder and checked out otherwise.

http://www.10-8forums.com/ubbthreads/postimages/77993-223primers.JPG

However, two problems were discovered. First, some of the primer strikes had insufficient firing pin indentations. The round from the potential OIS incident had a primer strike of only .013"—the minimum firing pin indent for ignition is .017". In addition, the primers on the other rounds were discovered to have been damaged from repeated chambering. When the same cartridge is repeatedly chambered in the AR15, the floating firing pin lightly taps the primer; with repeated taps, the primer compound gets crushed, resulting in inadequate ignition characteristics--despite what appears to be a normal firing pin impression.

Since then two additional AR15 failure to fire episodes have occurred with other SWAT teams around the country during OIS incidents, with other brands of ammo.

The Army is also aware of this problem and put out the following guidelines in the fall of 2008 to limit re-chambering to 5 or less times (4 times too many in my book...):

http://www.10-8forums.com/ubbthreads/postimages/78110-ArmyPrimerDents.jpg

The current military fetish on constantly loading and unloading creates more problems than simply leaving the weapon "hot".

Re-chambering handgun ammo can also cause problems due to bullet set back and damage to the case rim from repeated extractions.

Bottom Line: Once a round has been chambered, DO NOT RE-CHAMBER IT AGAIN for duty use--relegate it to training only. This is CRITICAL!!!

woody
01-29-09, 16:42
Thank you for the reply.

Glock17JHP
01-30-09, 13:27
I agree with only chambering once... I think this is a good idea with all firarms that 'cock' when the chamber is loaded (in other words, this does not include revolvers, etc.)...

torrpd
01-30-09, 19:14
Do you have a link to the Army info?

zippygaloo
01-30-09, 19:29
So what do you do with those rounds now? How do you get rid of them?

DocGKR
01-30-09, 20:48
zippygaloo--Uh...did you carefully read the post? You dispose of the previously chambered rounds just like the post says in the last bold line, by firing them in training, where a failed primer is not a life threatening event.

torrpd--The first time I saw this info distributed by the Army was in the 01 December 2004 issue of "PS, the Preventive Maintenance Monthly".

zippygaloo
01-30-09, 22:16
What about the free floating firing pin hitting the primer before the round goes into battery?

What if the round never wants to go bang? Then what do you do with it?

bkb0000
01-30-09, 22:37
What about the free floating firing pin hitting the primer before the round goes into battery?

What if the round never wants to go bang? Then what do you do with it?

my FTFs get tossed into the treeline.

DocGKR
01-31-09, 01:37
"What if the round never wants to go bang? Then what do you do with it?"

What have you been doing with your rounds that fail to go bang currently? If you shoot enough, you will eventually find some bad rounds. It is not like they are radioactive waste or virulent biohazards.

Personally, if I have a failure to fire, I vigorously seat my magazine, rack my slide/bolt, then assess whether I need to continue engaging the target...

BigTime
01-31-09, 05:49
A wolff extra power hammer spring would be a good investment,while your at it check out a wolff extra power extractor spring.

Glock17JHP
01-31-09, 13:59
I don't like changing springs from the original design...

For AR-type weapons, I prefer to not chamber a round at all if the weapon is to be stored. I would seat a full magazine...

If I was going out into 'combat, I would load a round into the chamber, and would want to keep the safety engaged and my finger off the trigger. If I had to unload it, I would first remove the magazine, then I would eject the chambered round. This previously chambered round would then be set aside/saved for the range/plinking...