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BlackRifle313
09-06-2008, 5:21 PM
I took my brand new AR build out to the IPSC range today and ran throught some courses with it and it functioned beautifully ,although I noticed when I would clear the gun and eject the unfired round from the camber they had tiny little dents on the primers and the only explanation I could come up with was when the round chambered the inertia was causing the firing pin to lightly tap the primer. This worried me a little because I thought that could cause a slamfire. Any comments/ideas on fixing this or has anyone had the same thing happen? Thanks

DedEye
09-06-2008, 5:25 PM
Use reputable, factory new ammo and there shouldn't be any cause for concern.

BlackRifle313
09-06-2008, 5:37 PM
I dont think I will be able to buy factory new ammo due to cost. Im planning on reloading with Federal match primers, what do you think.

eaglemike
09-06-2008, 5:58 PM
Federal primers are pretty soft. There was a time when they were specifically recommended for use in AR-type ammunition. I would not use them, instead use Winchester or CCI.

all the best,

Mike

Xerxes
09-06-2008, 6:46 PM
I took my brand new AR build out to the IPSC range today and ran throught some courses with it and it functioned beautifully ,although I noticed when I would clear the gun and eject the unfired round from the camber they had tiny little dents on the primers and the only explanation I could come up with was when the round chambered the inertia was causing the firing pin to lightly tap the primer. This worried me a little because I thought that could cause a slamfire. Any comments/ideas on fixing this or has anyone had the same thing happen? Thanks

This is normal.

It has a free float firing pin like most military rifles.

A lot of civilian rifles have spring loaded firing pins that keeps the firing pin back except when struck by the hammer.

Military primers are harder (so they say, not sure if it is still accurate with todays manufacture) so a light strike causes no harm.

Some say there is a danger with civilian primers in military weapons as there were some very very old stories repeated over the years but I do not know of any now other than the slam fire incidents which is a little different as that usually (not always) means a hammer following the charging bolt.

Just always remember to keep weapon pointing in a safe direction, especially when charging the firearm and make sure you maintain and clean your weapon and you should be good to go.

6079Winston
09-06-2008, 6:50 PM
The tiny dent is pretty much normal with most semi auto's, even with factory ammo. If the rifle's headspace is correct, cartridge headspace is controlled in reloading and hard primers are seated a few thousandths of an inch below flush with the case head, all should be well. For more info google or search this site for reloading for service rifle, cartridge headspace or something like that.

ar15barrels
09-06-2008, 11:39 PM
Completely normal behavior.
Slam fires COULD happen, but don't.

The likelyhood of it happening is quite similar to being struck by lightning.
So if you get struck by lighting one day, hold of shooting that day.

Think about this...
Every time you chamber a round, the firing pin taps the primer.
Every single time, I'm talking every single round from the magazine too.
Every single time the bolt closes at full power via the operating spring.
Every Single Time.

How many times have you heard of slam fires?

zcktomcat
09-07-2008, 12:18 AM
theoretically a titanium firing pin would reduce the likelihood even more. Though they are a bit expensive.

aplinker
09-07-2008, 2:36 AM
How many times have you heard of slam fires?



http://www.calguns.net/calgunforum/showthread.php?t=118458

ar15barrels
09-07-2008, 9:06 AM
http://www.calguns.net/calgunforum/showthread.php?t=118458

High primers, not factory ammo.
How many you got with factory ammo?

Paratus et Vigilans
09-07-2008, 10:22 AM
I had one. My own fault. When I first started hand loading for high power service rifle. The primer was properly seated, but the bullet (80 gr SMK BTHP) was seated too long. I think it didn't chamber as fully as it should have. When I hit the bolt release I got a slam fire as soon as the bolt flew forward. Startled the hell out of me. :eek: Never happened again, hope it never does. However, just in case, I always use CCI primers for ALL my AR loads, not just my high power service rifle loads.

When I got my first Garand, I read up on the dangers of slam fire with hand loads for the M1, and as a result I always inspect each round that comes out of my Dillon 650 for all my free-floating firing pin weapons to be sure that the primer is seated deeply enough, both visually and by touch, before it goes in an ammo box for shooting. Evey now and then I find a high one and run it back through the primer seating stage (gently but firmly) to correct the issue.

Nevertheless, I never chamber a round in an AR or Garand or M1A until I'm on the firing line and ready to shoot. Just in case. Safety First!