Dad and I went to the range today and he was shooting his factory Colt 6450 and was getting light primer strikes pretty consistently.
Ammo was S&B.
We could see the primer strike so we hung onto the rounds to try them later. We than fired the ammo with the light primer strikes through a luger without issue.
Checked the hammer spring and it was installed correctly.
I have know idea what it could be…
As it’s a factory carbine I’m assuming all springs are as well. Maybe a few items to check or think about.
Does it work with other 9mm ammo?
Did you retry any of the rounds in the carbine a second time?
Do the primers appear to be at proper depth?
Did you take apart the BCG to ensure there is no obstruction in the channel?
Did you inspect the firing pin for nicks or chips?
Hobe -
As it’s a factory carbine I’m assuming all springs are as well. Maybe a few items to check or think about.
Does it work with other 9mm ammo? Yes, in the past no issues.
Did you retry any of the rounds in the carbine a second time? No, didn’t think about this.
Do the primers appear to be at proper depth? He has the remainder of the box with him at home, I will have him check.
Did you take apart the BCG to ensure there is no obstruction in the channel? No, but it would fire one round, light strike the next, rack the charging handle and fire the next. Leads me to believe there is no obstruction.
Did you inspect the firing pin for nicks or chips? No, but I will have do that as well.
Is the hammer spring broken? Take it out and examine it.
It is the S&B ammo IMHO.
C4
I’ve seen this several times, mostly with revolvers that have spring kits installed and the hammer spring is too light. The fact that a different gun or even the same gun makes the once failed cartridge go “bang” on the second try is meaningless. Particularly I bought used a Ruger Redhawk 44 magnum with a light spring and I was lazy about replacing it. I shot it for several years before I fixed it. Every single cartridge that failed to fire went bang the second time it was hit. On the other hand I set up an AR for 5.45 but declined to put the extra power hammer spring in. When I got a non-bang I would try the cartridge again. Sometimes it would fire on the second strike, sometimes not. I had a hammer spring break on my LMT which is set up for 22 long rifle. The broken piece jammed the gun but once removed it produced light strikes that frequently caused a misfire. Round count was about 25K. I put a center fire upper on that broken lower and it would not fire a cartridge on the first try at all but fired every cartridge on the second try.
+1, S&B has a history of this in other firearms too.
I’ve also heard of S&B “light primer strikes” on the 1911 forums… Ron
I’m really surprised that a stock 6450 would not light off any commercial ammo with it’s heavy factory hammer spring. It should smack that primer with way more force than any handgun firing system would.
Thanks for the feedback everyone…this is my M4…RushCA01 posted this from his place after our range trip…all the springs are intact and original factory…this is only the second time out with no issues, the first go around using misc left over 9mm lying aroung the house, about 100 rounds down range in the first trip
First time out with the S&B…bought a case of it.
I will try again with different ammo and see it that resolves the issue.
If so I may have almost a case of S&B 9mm for sale cheap:p
We will post update after the next range outing