kstone803
Official Meat Getter
So this happened a few days ago but I'm just now getting to writing this up. The pics you see below are the result of an out of battery detonation in my AR9. Before anyone says, oh I bet it was a double charge, no it was not. There are multiple pieces of brass with telltale signs (see pics) and I happened to be running this mag over a chrono when it happened. The gun is a hodge podge lower build with a 5 inch alpha shooting sports 9mm upper. Upper has an unknown number of rounds through it but at least 500, more likely 1000+. All of these have been reloads from the same press these incident rounds were loaded on. The previous loads have been 124gr bayou over 4.0gr of N320 and 147 HST over 3.8gr of N320. Never had an issue with these. The issue was with some blue bullets 147 round nose over 3.6gr of N320. I'm not blaming the bullet at all here, just saying these are what it happened with. This load shot great out of my pistols when I tested it. All of these rounds were loaded to the same COAL (don't have it handy, currently sitting in a tree stand). The issue is these rounds apparently did not fully chamber but were still able to be fired. Some of the spent cases have bulged ends as you can see in the pics but not all of them. Additionally some of these have pierced primers. Following the OOB detonation I cleaned the gun real well and tried it again with a shorter COAL. Same thing happened. All of these are loaded on a 650 with a lee factory crimp die in the last station. I then took the upper off, bolt out and plunk tested a few different rounds. Sure enough these sat almost 1/4 inch out of the chamber more than the rest (see pics, brass is the 147 blue bullet, nickel is a factory 147 gold dot). I couldn't even smash them in with my thumb. Very odd.
So I'm assuming the gun shouldn't have been able to fire while OOB? Something wrong with the upper or do I just continue to use the loads I know that work? Perhaps an out of spec firing pin? I had issues with the upper when I first got it (ejection and feeding) but got these resolved by bending the ejector and adding quarters to the back of the buffer tube. Both are fairly common AR9 issues and easily found fixes online. Anybody have an experience like this? I've searched online but couldn't come up with anything similar. Thanks and for you gurus out there trying to help me I can provide more info on gun, ammo, etc, just ask.
So I'm assuming the gun shouldn't have been able to fire while OOB? Something wrong with the upper or do I just continue to use the loads I know that work? Perhaps an out of spec firing pin? I had issues with the upper when I first got it (ejection and feeding) but got these resolved by bending the ejector and adding quarters to the back of the buffer tube. Both are fairly common AR9 issues and easily found fixes online. Anybody have an experience like this? I've searched online but couldn't come up with anything similar. Thanks and for you gurus out there trying to help me I can provide more info on gun, ammo, etc, just ask.