Problem with 223 reloads

[Gunsrruss]

Ok More to the die

After you hit the shell holder with the die, then give it another half turn forcing the shell plate down. This way you know that the case will be fully sized. I learned this the hard way. You have to do this with .308 also. There will be those that will disagree. It does work

[thomashoward]

question, do you trim your brass?

Measuring case length would be a good start. Some guns have sloppy chambers, maybe yours is exceptionally tight. Get a dial caliper that measure to thousandths .001
Might just be the brass is overly long. No amount of sizing will fix that without trimming.
Dies should not be set to move the shoulder back excessively as this creates head space, which leads to head separation. If sized too much when the case is fired it has to stretch to fill the chamber. Once the case has been fire formed I neck size only. also there are Go/No go gauges. If the action closes on the case its not too long but maybe too short.

[Fjold]

One other very common problem is having your seating die adjusted down too far. The case mouth hits the step in the seating die and pushes the neck back. This causes the case to bulge just below the shoulder making it difficult to chamber.

You can measure the diameter of the case just below the shoulder and compare it with factory ammunition to check this.

Adjust your seating die out 1/4 of a turn and reset the seating plug to correct the OAL and then try your ammunition fit.

[tackdriver]

Oh ya. All cases have been measured. All I can come up with is that there is some sort of microscopic difference in the good vs bad rounds that I cant find. I believe my chamber is pretty tight. These "bad" rounds shoot fine through my Mini 14.
"
Nice being able to shoot the rounds in the $500 Mini when the $2000 AR cant handle them.....sigh...

[FLIGHT762]

If you don't have one of the three common headspace gauges (the RCBS precision mic, The Hornady headspace gauge or a Wilson style case gauge) you are just guessing at how much shoulder set back you are getting when you are sizing. Just a 1/12th of a turn in your sizing die can make the difference. Here's a short article that explains how to use the Hornady. I like the Hornady because you can clearly see the numbers in a digital caliper.

http://www.inlandshooters.net/index.php?contentid=99

[22popnsplat]

[QUOTE=tackdriver;6442752]
I can NOT for the life of me figure out what the problem is. I do not have this problem with manufactured ammo or ammo that I've loaded with my FL die. QUOTE]


I read through this whole thing with the above statement stuck in my head . Who made the small base die ? If you are having the problem when you use the small base die but the rounds function fine with a full length die then the problem is either the small base die or the adjustment of the die . If you are sure you are usning the die as per the instructions then its the die.
My guess is your brass is out of spec just above the case head .

[760knox]

http://youtu.be/xfpGFZm8Ed8

[SixPointEight]

Probably the shoulder is not bumped down enough. Use a comparator to measure the shoulder to base length. Basically it's too long for the chamber of your rifle.

This. I pretty much guarantee it. I know because I did it too