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80viking
December 27, 2009, 07:17 PM
I was just thinking about something that happened to my son an I two years ago at a shooting competition at my gun club and I thought it well worth posting, I bought my Bushmaster XM-15 in nearly new condition from a gun show back in the early 90's and have put thousands upon thousands of rounds thru it without any problems except maybe a magazine malfunction or three, my son 12 at the time was on the firing line and as usual I was watching closely, he took the magazine [with the gun pointed in a safe direction of course] and inserted it into the magwell, then he depressed the bolt release and made the gun ready to fire, he raised the rifle aligned the sights and squeezed the trigger, nothing happened, I asked him what he did, he said I don't know, then he says ''the safety is on'' so he flips the safety lever to fire and the gun goes off the bullet struck the ground about 15 feet in front of him, after inspecting the gun I determined it was ok for him to fire his string, now I need to mention that I don't like, trust, or use safety's unless your hunting animals or badguys and also I had a friend with me that day who is a LEO trained from birth to use a gun safety, he was also using my bushmaster, it didn't take long to figure out what happened, he used the rifle before my son and when finished with the gun empty and the bolt locked back he put the safety on and returned the gun to the rack, when my son who was never taught to use a saftey [my guns are only safe when they are unloaded, action open, and pointed in a safe direction], tried to fire the gun with the safety on, partially disengaged the sear from the hammer because of an improperly fitted safety, and when the safety was turned to the fire position the hammer released and fired the gun, this unsafe condition of my rifle was unknown for over 15 years and somewhere between 20,000 and 40,000 rounds

TO CHECK YOUR RIFLE
*point the muzzle in a safe direction
*check to make sure the gun is unloaded
*with the safety in the fire position pull the charging handle back then lock the bolt back
*release the bolt
*turn safety to the safe position
*attempt to fire the rifle by squeezing the trigger
*now without touching any other controls on the rifle, turn the safety lever to the fire position

if nothing happens you are good, if the hammer falls you need a new safety lever and for it to be properly fitted to your rifle

Catfish25p2000
December 27, 2009, 07:35 PM
Thanks! I will check my rifle tonight. :D

Technosavant
December 27, 2009, 07:52 PM
Generally, AR safety levers don't need to be "fit" to the gun. It should be drop in. If it isn't, then something is out of spec and in need of replacement.

It's good to do regular function checks, and if the trigger group starts getting iffy, then I'd be liable to just replace the hammer, trigger, disconnector, and safety as a whole.

Gbro
December 27, 2009, 08:44 PM
Good info Viking,
I have covered that same thing in my firearms safety classes for many years. It is a standard part of the Canadian Firearms Safety program. That is where I first heard about it.

tirod
December 27, 2009, 10:37 PM
I would venture to say that if the hammer falls, it's not the safety, but the disconnector that failed. Expecting trigger components to remain perfectly safe without wear for over twenty thousand rounds isn't wrong, but is indicative of the unknown quality of the parts that went into an gun from an unknown source.

The safety check is certainly important, but attributing the cause without a close examination of the components and an understanding of their actual function may be premature.

UnlessofcourseIcompletelymisunderstoodthecircumstancesbecauseIcouldn'tcomprehendthepostduetoacompletelackofpunctuation.

I guess.

impalacustom
December 27, 2009, 11:44 PM
The safety didn't fail it was as Tirod said, the trigger or the catch on the hammer is simply worn out. You should test your FCG once in a while so those things don't happen. I have worn them out and mine was so bad that just letting off the trigger would drop the hammer after the disconnector let go of the hammer the trigger was so worn that it wouldn't catch.

Tim R
December 28, 2009, 02:08 AM
Generally, AR safety levers don't need to be "fit" to the gun. It should be drop in. If it isn't, then something is out of spec and in need of replacement.


Not always so. When you install a Greissle 2 stage trigger, chances are you are going to have to fit the safety. There is more than likely a little metal needing to be taken off one side of the safety switch. Not hard to do at all, just follow instuctions.

As far as a AR going off on it's own after the trigger is pressed with the safety on, I believe it should be looked at for parts wear. There is bound to be some wear on something after 40k.

80 Viking....Now I'm going to suggest you change your thoughts on using the safety.

1. NRA and CMP High Power rules call for putting the safety on safe when loading.
2. I understand some of what you are doing, I carry a Glock for duty and a 1911 for off duty. I carry the 1911 cocked and locked.....always.
3. How long is it going to take you to figure out the safety is somehow on when you need the weapon NOW?
4. Your LEO buddy did what he should have done....

Technosavant
December 28, 2009, 10:46 AM
Not always so. When you install a Greissle 2 stage trigger, chances are you are going to have to fit the safety. There is more than likely a little metal needing to be taken off one side of the safety switch. Not hard to do at all, just follow instuctions.

I'll admit that I have no experience with 2 stage triggers. Given their closer tolerances for match use, I am not surprised fitting needs to take place. My comment was referring to the standard parts.

Willie Lowman
December 28, 2009, 02:11 PM
It is entirely possible the kid in the first post still had his finger on the trigger.

Don't get mad at me if it was your son, everyone makes mistakes.

My Colt HBar II, I can pull the trigger with the safety on and nothing happens. If I release the trigger and turn it to 'fire' noting happens. If I hold pressure on the trigger, the hammer will drop the moment it gets to the fire selection.

My RRA mall ninja rifle, The safety works as the Colt does except when I have pressure on the trigger as I start to release the safety. When the safety is half way between safe and fire it will rotate to fire and the hammer will drop just from my pressure on the trigger.

80viking
December 28, 2009, 08:45 PM
thanks for all the replies and comments everybody

I bought my rifle the from a CT gun dealer at a MA gun show the year that CT banned the sale or transfer of ""assault rifles'', I would be willing to bet that it is not a factory assembly, the barrel is marked CMP HBAR 1 in 7 twist, I believe that would make it a Colt barrel, now the trigger, 3-4LB pull, crisp, w/ very little over travel, with what appear to be standard single stage parts, all things that are difficult to do with standard single stage trigger parts, let alone doing it without welding or cutting and heat treating, does anyone make an after market trigger that appears to be all stock?, interesting thing about the safety, the original one that I took out had a significant amount of material removed from it, with the tell tail grinding marks on it, the new safety I bought from the DPMS web site, also needed material removed from it, when I put the new part in the lower receiver I could not turn the safety lever because the cam or bump on the new part would hit the trigger body so with some careful fitting I got all the parts to work properly.

As for what happened the day of the AD, my first thought also was that my son made a mistake, but after examining the rifle and being able to repeatedly duplicate the malfunction there is no question as to what happened.

I don't know why or how my gun was like this, fact is it was and I had no idea about it for a long long time [what year did CT ban ''assault rifles''], the reason I wanted to post this is maybe I could help prevent another AD. :)

NWCP
December 28, 2009, 09:07 PM
Sometimes it doesn't hurt to have a professional gunsmith look at a problem.

Warchild
December 29, 2009, 07:31 AM
Good info, never hurts to have a refresher from time to time to keep you frosty.

HiBC
December 29, 2009, 07:49 AM
I note you sai this trigger has minimal overtravel.
I cannot say that is the issue for sure,but I do understand that a sear needs a bit of room to beak away.Without sufficient overtravel,an almost breaking,but not quite,sear can hang on the corner,and taking the safety off will cause it to fire.This condition I have observed in bolt action adjustable triggers.

It is also possible that a safety (such as the 1911),when properly fitted,allows zero sear movement when the trigger is pulled when on safe.An improper safety allows partial sear disengagement,where the sear spring does not return the sear as the pressure is lifted from the trigger.

These are general suggestions ,and exactly how they apply to the AR trigger in place will have to be observed

80viking
December 29, 2009, 12:24 PM
''It is also possible that a safety (such as the 1911),when properly fitted,allows zero sear movement when the trigger is pulled when on safe.An improper safety allows partial sear disengagement,where the sear spring does not return the sear as the pressure is lifted from the trigger.''

yes, these are the exact conditions that were taking place to cause the AD

44 AMP
December 30, 2009, 12:32 PM
If you pull the trigger with the safety on, then release the trigger and take the safety off, the gun should NOT fire. Period.

If it does, you have worn/broken/misaligned/misadjusted parts. Or possibly you haved enough grunge in the trigger group to prevent the trigger from returning to the proper position (unlikely, but not impossible).

In any case, you need to have the rifle fixed. It is only a very small step mechanically from the incident you described to having the hammer fall when you release the trigger. NOT GOOD.

some people might consider it "only" 20,000 rnds, but that is a lot of ammo. Parts wear. Nothing lasts indefinately, especially under that kind of usange.
Get the gun fixed.

Jimro
December 30, 2009, 01:14 PM
Stock AR trigger/safety kits are cheap, and plenty easy to install with a little time and cussing. Peace of mind is priceless.

Jimro

tirod
December 30, 2009, 08:14 PM
If you have to grind on an AR safety to fit it, something is not spec. I suspect the trigger was worked on, simply because of the low pull weight and that there was no room to fit the factory safety.

It's exactly the symptom of an overtravel screw adjusting the trigger slack and removing it completely.

Thousands of enthusiasts have built AR's from parts kits and milspec is that all the parts drop in without any grinding or alteration. Hand fitting isn't necessary to produce a functional rifle. If anything, the factories just pull another trigger out of the bin and try it - if a low pull weight is even a factor on that lower.

Gritty, 8 pound triggers are military standard, and milspec is standard for most brands out there.

Something is NOT standard with the trigger in question here. A three to four pound trigger is for target range use and will be susceptible to accidental discharge in inexperienced hands.

I would not trust that rifle until an experienced AR gunsmith can check out what has been done and can explain it - and repair it.

80viking
December 30, 2009, 10:23 PM
I was thinking about getting a drop in unit from Chip McCormick or Timney,any idea if these would be NM legal?

Tim R
December 30, 2009, 10:47 PM
An RRA 2 stage is well worth the money but if you have the $ the Geissele would be devine.

HiBC
December 31, 2009, 12:00 AM
I can't tell you about what fits rules.I agree an RRA is a nice stock type trigger.I have used a Jewell,very nice adj 2 stage.

Jimro
December 31, 2009, 12:22 AM
Timney makes a drop in 4 pound trigger, which I think is NM legal.

Jimro