AR not going into battery consistently - Help!

Melnibonean

Melnibonean

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Hello fellow CGNers,

First, let me start off by saying I've been reloading pistol ammo (9mm and .45) for over a year now, so I know my way around the Dillon 650.

My problem started when I began reloading .223 from once fired brass picked up at the club. I just got my AR last month (1st one). I go through the following steps:

1) Clean in tumbler
2) Lube
3) Full length resize/decap at station 1
4) Trim to 1.75 using the Dillon 1200B trimmer at station 2
5) Use the case gauge to make sure I'm good (at start up, I gauge every case for the first dozen or so; then randomly every once in about 15-20 out of the batch I'm working on)
6) Clean in tumbler again
7) Begin reloading using a different tool head with only the powder/seater/crimper installed

The problem is that every once in a while (almost always on the first round out of the LAR mag then maybe another 1 or so further down in the mag), the bolt won't go into battery when I release it. It goes in most of the way and just sticks there. Using the forward assist does nothing. Using the BAD lever or the charging handle to let it go doesn't make a difference.

Not only won't it go into battery, but I can't manipulate the safety or extract the bolt. I have to drive the butt into the ground (or table) while pulling on the bolt to get it to retract. When I put all those rounds that stuck back into a LAR mag at the end of my session and try firing them (because I'm a masochist and like to see if I can frustrate myself all over again :p), they cycle and fire perfectly.

What gives? Anyone have any ideas what's going on here? The rifle is a Spike's, but it was bought as a lower and a complete upper seperately then simply mated together. The brass is regular UMC and Winchester scavenged from the range that has no visible damage to them anywhere.

Also, I don't know if this means anything, but on the rounds that stick and get extracted, the copper on the FMJ is deeply scraped in some places, and I can see some copper residue on the feed ramps.

Thanks guys
 
try checking to make sure you are full length resizing.right after your second operation of trim to length,take an empty case,no primer or powder and seat a bullet on it and try cycling it through the action.do this with several cases.the only thing I can think of is because it is not every round is perhaps some of your case necks are a bit "thick" and getting jammed in a tight chamber.another possibility is the neck expanding button on your resizing die is too large.take a case after resizing and measure inside neck dimension.also measure neck thickness at base of neck above shoulder.last thing I can think of is how aggressive your crimp is.it is possible to "collapse" the case neck.measure the stuck cases everyway you can think of compared to a factory round,see what the difference could be.
 
How about you try some descent factory ammo first. Then try a known reliable magazine. Hopefully before you begin butchering parts.
 
Run factory ammo if ok than its your reloads if not ok than your chamber

clean your chamber with chamber brush.
how deep do you seat the bullets?
what brand case gets stuck the most?
try using different mags at one point.
you have to break down the problem so you can figure out whats causing it. its called troubleshooting. try all these and let us know how it went
 
I had some problems with my new lar mags I lightly filed the front of the mags and feed lips and now they work great. I think your problem sounds mag related to me. 80% of all AR-15 feeding problems relate to the magazine!
 
If it was a mag issue, the forward assist should shove the round forward without a problem.
By driving the round into the chamber, not having it seat and then having to do a hard extraction grounding to clear it says a lot about either:
A) the case/round is not sized properly, or
B) your chamber is out of sorts

The mag in this instance is a red herring.
 
My problem was more how my mag was scratching the brass it was causing it to jam where the brass was built up at the end of the scratch. Or at least that's what I believe the issue was because after eliminating the scratch I eliminated the problem. But that was the problem I was having this may not be the same. My extraction was difficult but not as bad as he is describing. The other reason that I think it's a mag problem is due to those bad rounds feeding fine later which means it isn't a problem with those rounds in perticular IMO.
 
So you have ruled out mags. And your saying your rounds match specs. Double check shoulders. Clean chamber and bcg. Maybe some kind of builduP. 2x try factory ammo
 
I'd like to see some clear photos of the chamber and the extracted rounds with the scratches. Are you seating the bullets deep enough?

I overall agree with Beltfed on this as I understand you need to forcefully yank the cases out as they are stuck in the chamber, but what I'm thinking is that your feedramps may be a combination of an M4 Receiver and Rifle Extension. That's bad. Maybe that's where the scratches are coming from. Maybe the gouges are even impeding proper chambering.

Does Spikes Tactical even use M4 receivers?

med_gallery_256_101_104012.jpg
 
sorry I should have brought this up earlier,my brain was fully engaged with your reloading technique.I read a thread over at M4 carbine a while ago about shooting in cool or cold weather.what was happening to the owner of an M4 was a random failure to go fully into battery.after a long time trying to solve the problem he finally clued in to the rubber O ring under the extractor not allowing the extractor to yield and allow the claw of the extractor to ride over the rim and engage the extractor groove.I don't know if you have been shooting in cold weather or not,it may be a factor,and also you may have some previous damage to the rim of your once fired brass which will cause the same symptoms.that may explain why they chamber at the end of your shooting session,the damaged rim is not interfering with the extractor because it has indexed at a different position.examine the rim on your sticky cases,if you see damage,this may be the problem.the solution for cold weather shooting is to remove the rubber O ring.hope this helps.
 
These are all great suggestions. Thanks to everyone :cheers:

Here's an update. After reading all your posts, I decided to try factory ammo (UMC 55gr FMJ) in 2 different LAR mags that were both used when the problems occured. All 20 rounds cycled flawlessly. I had zero issues.

I then took the same mags and loaded them with 20 rounds of my reloads. Sure enough, the problem resurfaced.

At least this proves 2 things: It's not the magazine and it's not the chamber.

I kept the jammed rounds and checked the OAL. They were within specs.

The only other thing I can think of to try is to adjust the resizing die to make the case more narrow. Is this even possible? I have 2 different resizing dies: the Dillon and an RCBS. There is no literature for adjusting the die to make the case more narrow.

Is there another way?

I'll try and post some pics later on about what the rounds/chamber look like when this happens.
 
barsik said:
sorry I should have brought this up earlier,my brain was fully engaged with your reloading technique.I read a thread over at M4 carbine a while ago about shooting in cool or cold weather.what was happening to the owner of an M4 was a random failure to go fully into battery.after a long time trying to solve the problem he finally clued in to the rubber O ring under the extractor not allowing the extractor to yield and allow the claw of the extractor to ride over the rim and engage the extractor groove.I don't know if you have been shooting in cold weather or not,it may be a factor,and also you may have some previous damage to the rim of your once fired brass which will cause the same symptoms.that may explain why they chamber at the end of your shooting session,the damaged rim is not interfering with the extractor because it has indexed at a different position.examine the rim on your sticky cases,if you see damage,this may be the problem.the solution for cold weather shooting is to remove the rubber O ring.hope this helps.
Click to expand...

It was only used so far indoors. As for the rim, I will re-examine them more closely, but there was no obvious damage to the rim looking at it with a casual eye.
 
when resizing for semiauto firearms make sure the die gets positive contact with the shellholder at the very bottom of the stroke.do not overdo it,just make sure it contacts.set it up without any rounds in your press.try that and post results please.
 
This might be a long shot but it's a problem I had with rcbs dies a long time ago. Check the concentricity of the round. I once had a set of dies from rcbs where the sizing die was resizing the brass a little off and was causing a binding issue in the end all that was needed is a new sizing die
 
easy said:
I'd like to see some clear photos of the chamber and the extracted rounds with the scratches. Are you seating the bullets deep enough?

I overall agree with Beltfed on this as I understand you need to forcefully yank the cases out as they are stuck in the chamber, but what I'm thinking is that your feedramps may be a combination of an M4 Receiver and Rifle Extension. That's bad. Maybe that's where the scratches are coming from. Maybe the gouges are even impeding proper chambering.

Does Spikes Tactical even use M4 receivers?
Click to expand...

Yes, Spike's barrels all come with the M4 feed ramps and all their parts are mil-spec tolerances/measurements. I'm not sure who makes them for Spike's, but the parts seem very well made and robust
 
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