223 reloading question

[victor3ranger]

I have reloaded for bolt guns for 25 years, this is my first crack at loading for a autoloader so please bare with me.

I have been prepping and processing some LC brass and have run into something. Brass was resized with a RCBS FL die and cases all trimmed to spec. Two days ago I had a brain fart and wanted to check how easy the brass would fall into and out of the chamber. The AR has a NATO chamber. Half the brass would drop into the chamber and fall right back out while others I could feel resistance when pushed in with the tip of my little finger. Some of these I would have to extract with my bolt/carrier.
Of the brass that didn't fall out of the chamber I took these and tried them again in a different AR with NATO chamber and all fell into and out of the chamber without any problems.
For those of you who have reloaded for these rifles, do you think I need a SB die to ensure function and reliablility for the AR with the tighter chamber??

 

[NikatKimber]

Maybe. I had brass (before I got a SB die set) that was so tight in the chamber that it took putting the butt of the rifle against my chest, and using both hands on the charging handle to extract. They still fed fine, and I never noticed the issue in live fire (put about 10-15 round through it before trying to clear manually).

 

[BadKarma]

Anymore I use a small base die for my Ar 15 loads. It works the brass a little more but
I've never had to unstick one since. I have a great source for free brass so wearing it out
a little sooner isn't an issue for me.

 

[dennishoddy]

I had this problem with FL dies in the past. There are inconsistency's in chamber diameters.
RCBS told me to screw the sizing die down 1/4 turn more and my problem went away. I've heard a couple of others having this problem, and passed this along to them. Their problems went away as well.

 

[victor3ranger]

I tried screwing the die in further, to the point thatI was almost not able to cam the press, still didn't help. I even ran some of them thru the die multipal times and would let the brass sit in the die for a few extra seconds and still didn't change.

 

[dennishoddy]

Well, it looks like you may have to go to the SB die then.
Have you tried putting some of your rounds in somebody else's rifle? I dunno, just throwing stuff out now. Wondering about a tight chamber on yours?

I would also call RCBS with your problem, since you are using their dies. They have free technical service over the phone. I'll bet they tell you to shoot 5 rounds, and send them back with the dies. They will custom grind your dies to fit your chamber at much less than buying a SB die.

Here is their tech support info so you can contact them.

phone: 1.800.533.5000
fax: 530.533.1647
[email protected]
www.rcbs.com

 

[tyromeo55]

Order a Dillon case gage and use it to set up your dies. A lot of issues went away for me when I started doing it that way. You could have a tighter then normal chamber or one that is head spaced improperly. Is the gun in question a factory build or home smithed? have you made sure that the chamber in the gun us not packed with carbon or lacquer from shooting steel cased ammo? if you are just sure that everything is clean and set up properly then I guess you could have a bastard die they do differ a slight bit from brand to brand and die to die. you could send it back to the MFG or even sand a couple thousandths from the base.

 

[aeropb]

Shoot some and see if it functions just fine. If it does not, get some small base dies.

 

[victor3ranger]

To answer some of the questions.
I have tried three different sets of dies, all with the same results. 2 RCBS and 1 LEE.
I have cleaned and cleaned the chamber, inspected with a bore light, everything is spotless, so that isn't the problem.
I have also taken two other AR's with NATO chambers and the brass falls into and out of the other two, so I am leaning towards this one AR having a tighter chamber.
I went ahead and ordered a SB die, so when it comes in I will take some of the tight fitting brass and run it thru the SB die and check it again.
It feels like the last 1/8" or 1/16" or so of the brass above the base isn't getting squeezed down enough with the FL die.
Sure hope it solves the problem.
If it dosen't I will see if I can do what you guys say about sending in some of the brass and one set of my FL dies back to RCBS.