Home Forums Hunting & Shooting AR and Tactical Rifles Question on C.O.L. for .223 for my AR

Hi rost495. Answer to the too short question,
1. Pressure- mostly if near max loads
2. Trouble feeding
3. Yes, bearing surface & capacity
4. Accuracy, because of possible pressure spikes
Jim D

^^^^^This is what he should do to determine if he has a leade problem.

Or he could put a bullet into a slightly pinched fired case so the it is tight enough to stay in place but loose enough to be pushed in as it's pushed into the chamber & lands.

A chamber/leade that will only allow a 2.200" 55 v-Max is pretty unusual.........I suspect he's missing something & that something else is going on. If it's really that short, it's out of spec.

MM

You mean, it is supposed to be a 5.56 Nato chamber. If it really was, you wouldn't have this issue.

Sounds to me like someone screwed up and used a 223 Rem reamer instead of 5.56. I'd be sending it back.

Take a bullet and drop it into the chamber, lightly tap it with a cleaning rod with a flat jag or something screwed in, (just so the bullet doesn't fall out when you turn it upside down). Insert the rod into the muzzle carefully until it touches the bullet, mark rod with a sharpie at the edge of the muzzle.

Punch bullet out, insert bolt and carrier, drop rod back into muzzle till it bottoms out on the bolt, mark rod at muzzle, measure in between lines and that will be your COAL.

If it's longer than 2.260, it won't fit into a magazine and won't be a problem (have yet to see one throated that short). If it is shorter, then get on the phone with DD as it ain't supposed to be like that.

Thanks for the tips guys. I'm really scratching my head right now. I asked my buddy to bring over his DB chambered in 5.56 to see how his gun chambered with these reloads. Same issue, sometimes the bolt doesn't fully close and if it does close, its next to impossible to eject the unfired round. The marks I am seeing on the bullet may not be rifling marks but marks from the lugs. I have checked all the brass with a case gauge and they drop right in. I purchased this brass fully processed but I do double check it with my gauge. If it is happening in both guns I assume it is something I am doing wrong. What am I doing wrong???

I am trying to upload some pics of the bullets but my internet is giving me troubles. Phone company is coming out tomorrow so hopefully tomorrow night I can get the pics up.

If it won't chamber in 2 different guns, I'd be betting on the brass itself as I doubt 2 guns would both have a short throat.

Either the case diameter above the rim or they may have pushed the shoulder too far forward during sizing w/o pushing it back to within headspace limits, hence the headspace is too long.

MM

That's what I thought those marks would be. Run the cases that don't chamber through a FL sizing die setup for your rifle. Seat the bullets at 2.250 and see if they chamber. If I got surplus processed beads, I would still run it through my die to make sure. You can't trust someone else's work.

If the shoulder was set to far forward wouldn't the brass not set properly into my case gauge?

Don't know what your case gage us measuring.......I check heaspace with a headspace gauge & can actually measure (in .001") difference from a new case or any fired case or any resized case & compare that directly to SAMMI headspace min to max.

New brass is usually about .003" below minimum heaspace chamber spec so as to chamber in any gun that is in spec.

On an AR, I will size my brass back to .002-.003" below what is was after firing in any given gun to be used in that same gun again, or if to be used in just any old AR, not necessarily the one it was fired in, I'll size it to .002-.003" below minimum chamber specs or back to about what original new factory brass is.

You need some actual measurements to compare to factory brass.

MM

Those marks are from chambering, not from contacting the rifling, as someone in this thread already mentioned. Do you know where the rifling actually contacts the bullet?

You have a brass sizing problem, and need to size the brass to fit your chamber. Difficult ejection of live rounds in an AR is almost always a brass issue; that's the first thing to check when you encounter this.

Thanks guys! I will have to do some homework on other ways to check my brass instead of the case gauge I have pictured as it must not be working correctly.

if factory shoots fine in your rifle, then set your dies up like the manufacturer recommends and you should have no problem. Some times you might even want to call the die manufacturer as they have "seen it all".

To set your dies up correctly you really need a set of bump gauges. Measure a factory case that was fired from that rifle, then set your dies so that you are bumping the shoulder back .002"-.004". Any more than that is over working the brass and any less can cause issues in a dirty rifle. Instructions that come with dies are a shot in the dark, you have no way of knowing how much you are sizing your brass without the right tools.

If you don't already have them, all reloaders need a good set of calipers, a set of bump gauges (hornady or sinclair), and a OAL gauge (hornady). Without these tools you are just guessing.

Take a deprimed 308 Win case and slide the neck over the neck of a deprimed fired case from your rifle, place them in a caliper, center the primer pockets over the jaws, tighten the jaws, and wiggle a bit to see what your shortest measurement is. Do the same with the problem brass. You'll most likely find your answer.

You want your sized cases to be .002-.004 under the length of cases fired in your rifle using the above method.

That's not the best way to measure, but works when you don't have the proper tools.

Its a defective barrel. The rifling marks indicate the rifling is totally messed up and won't shoot worth a flip, might even be dangerous.

I've never seen rifling marks so crazy and uneven.

Possibly though a new type of gain twist?


LOL.... I think they've pointed out your real issue though...

Yep, I probably jumped the gun with thinking my COL was the culprit.

Ordered some OAL and headspace gauges. I will report back with the results.

Thanks again to all for walking me through this.

Hey, we all start somewhere... should have seen me 30 plus years ago with a new 300 wtby, and had not read correctly about crimping... ended up with bulged shoulders and could not figure why. LOL.


Hope you get it all figured out. Once you do its not hard at all!

Check your mags. It looks like scratches caused by a sharp corner on the front, inside edge of your magazine.
I've had to smooth up more than one mag with a file.

Or shoot as is, scratches on bullets don't hurt.