titanium firing pin for AR

I've experienced several slam fires as well. With old well used M16A1's but the bolts still stayed in the carriers when turned over while stripping, so the gas rings were not that bad, yet it still happened. Anyone who says they haven't ever seen a slam fire, just needs more time and rounds through the ARFOW's, shoot enough and you will see it.

Rich
 
pauls said:
The gun is a competition gun, not a "work" gun.
Has light weight bolt carrier and buffer, so the carrier velocity is faster than what you would typically find in an AR.
Everything is well within spec and high quality.

The ammo is Freedom Munitions. Seems their primer cups are thin enough that I'm getting intermittent doubling (3 or 4 per 100 rounds) in my main competition rifle.
That's unacceptable.

By reducing the mass of the floating firing pin, I'll be reducing the mass of the object slamming into the primer every time the gun cycles.
This should eliminate the odd doubling I'm getting with this ammo.
If it does, I have ammo I can use in competition and don't have go spend $1000 to replace it.
If not, I'm out $40. I won't buy Starbucks for a few days and I'm no worse off.

In the competition world, Ti firing pins are a common remedy for this not uncommon problem.

Slamfire/doubling can be caused by a number of things:
- sticking/dirty firing pin
- bump firing
- improperly functioning disconnector/hammer follow
- primers too sensitive for AR use.

I know the cause of my issue, I'm trying the least expensive possible remedy first.

And to keep this thread on track, the results of the paternity test are back, and I'm NOT the father!
Woo Woo Woo Woo.
Jerry! Jerry! Jerry!
Click to expand...

A competition gun with competition parts is not within spec. It is either mil spec or it isn't, and your rifle isn't which means all bets are off. You're also running remanufactured ammo which is sketchy at best and not mil spec ammo. Why you would want higher BCG velocities is a bit of a mystery as the perceived faster cycle times are mostly in your head and the potential advantage is clearly being out weighed here by an unsafe rifle. Even with a non mil spec gun and ammo, my bet is on a worn or damaged sear/disconnector. Bump firing is a phenomenon perpetrated by the user not the gun so that isn't the issue. A sticky/dirty firing pin is a hard sell. Have a look for "filthy 14" that ran some 43000 rounds without any slam fires or major issues.

So what make is the gun and the guts??

TW25B
 
Now that I think about it, I've had double fires with my COMPLETELY FACTORY REC7. It was with garbage ammo, and hasn't happened since I bought some better stuff.

-J.
 
higher bcg speed is a byproduct of light weight components and not the reason for them.

properly tuned system of light bcg and buffer, adjustable gas block and compensator, when they are all working in harmony, the gun recoils like a .22
The less weight I have slamming into the back of the buffer tube and then fwd again, the less the muzzle moves.
In competition, tenths of a second add up quickly and the faster I can make an accurate second shot on target, the better.
The advantages are measurable on the clock and in my results at competitions.

My gun is safe.
Its the ammo that is giving me issues.
Does not happen with any other ammo.

Like I said, the Ti pin is a relatively inexpensive test to see if it solves the problem I seem to be having with this particular lot of ammo.
 
pauls said:
higher bcg speed is a byproduct of light weight components and not the reason for them.

properly tuned system of light bcg and buffer, adjustable gas block and compensator, when they are all working in harmony, the gun recoils like a .22
The less weight I have slamming into the back of the buffer tube and then fwd again, the less the muzzle moves.
In competition, tenths of a second add up quickly and the faster I can make an accurate second shot on target, the better.
The advantages are measurable on the clock and in my results at competitions.

My gun is safe.
Its the ammo that is giving me issues.
Does not happen with any other ammo.

Like I said, the Ti pin is a relatively inexpensive test to see if it solves the problem I seem to be having with this particular lot of ammo.
Click to expand...

The ammo you are using has had issues in the past, some catastrophic. You may gain tenths of a second or you may end up with a match DQ when you chamber a round and have an ND. The priorities for all firearms should be as follows. SAFE RELIABLE SIMPLE ACCURATE. In that order. It seems like you're trying to save the ammo when it seems to be the issue. Dump the garbage and buy quality fresh ammo.

A properly built mil spec gun with a quality compensator will recoil very softly. Rifle length being the softest but a proper midlength gun is a very close second. What system is on your gun?

TW25B
 
Rifle length gas.

Yes, I'm trying to see if there is any salvaging of this ammo.
It was practically free so I'm not going to feel too bad if I have to relegate it to practice only, but if I can use it safely at local and less important matches, I will.
That's the whole point of getting the Ti pin and doing the necessary testing.
Save my good ammo for the majors.
 
pauls said:
this thread really has no more value to me so I'll let you guys resume your never ending discussions on NEA quality control, bear defence and shooting into space.
Take care.
Click to expand...

I thoroughly enjoyed this comment.
 
pauls said:
Rifle length gas.

Yes, I'm trying to see if there is any salvaging of this ammo.
It was practically free so I'm not going to feel too bad if I have to relegate it to practice only, but if I can use it safely at local and less important matches, I will.
That's the whole point of getting the Ti pin and doing the necessary testing.
Save my good ammo for the majors.
Click to expand...

I guess a Ti firing pin could solve the problem, and on the cheap. I'm not convinced the weight difference would make a difference.

TW25B
 
I can't imagine a primer being an issue unless they were quite proud of the case head and poorly seated. IF it is slamfiring I wouldn't use the ammo even for practice in an AR - maybe in a bolt gun?
Curious to know what primers they use in that ammo? I use Federal 205m almost exclusively and never had an issue.
The firing pin protrusion on follow through on 205Ms has been no more noticeable than any other primer in my experience - and I go the other way with carrier weights to increase dwell - so if it is showing anywhere it would be for sure in my guns.

I would look at the tail of your firing pin and compare it with its interface in the carrier to ensure your gun isn't beating the pin through the carrier - likewise with firing pin protrusion and degradation of the firing pin hole in the bolt - but being a competitor in the fast lane I suspect you've looked at all of that...;):p
 
This is somewhat related to information that Dr Gary Roberts has posted regarding re-chambering of ammunition in the AR15:

"A large SWAT team in this area 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. 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.

However, despite what appeared to be good primer strikes, two problems were discovered. First, when accurately measured, some of the primer strikes had insufficient firing pin indentations. The failed 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. Once a round has been chambered, DO NOT RE-CHAMBER IT for duty use. Do NOT re-chamber it again, except for training. This is CRITICAL!!!"

Regards.

Mark
 
MWL said:
This is somewhat related to information that Dr Gary Roberts has posted regarding re-chambering of ammunition in the AR15:

"A large SWAT team in this area 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. 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.

However, despite what appeared to be good primer strikes, two problems were discovered. First, when accurately measured, some of the primer strikes had insufficient firing pin indentations. The failed 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. Once a round has been chambered, DO NOT RE-CHAMBER IT for duty use. Do NOT re-chamber it again, except for training. This is CRITICAL!!!"

Regards.

Mark
Click to expand...


I'm going to be blunt here.. NO SH*T... I put this under "common knowledge".

TW25B
 
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