Quote Originally Posted by BPTactical View Post
I am not familiar enogh with reloading but STOP SHOOTING YOUR RELOADS immediatley.


Not crimping the the reloads could be key here. Like I said I dont know much about reloading but if I am not mistaken when you crimp the bullet a couple of things happen:
1-The bullet is seated a bit deeper in the case.

This is not true, the seating depth has nothing to do with crimping. You can seat your bullet as deep as you want, crimp or no crimp.

2-The crimp provides a bit of a taper for the "Leade" of the chamber. The leade is the unrifled portion of the chamber where the bullet is. It provides a head start for the round when fired before the bullet enters the rifling. Some people call it the "Throat" of the chamber. If the round is crowded into the rifling you will get a pressure spike.

This is not necessarily true. Lots of people seat into the lands.

The uncrimped neck could possibly be crowding the round a bit and spiking.

Again, this has nothing to do with crimping, it has everything to do with seating depth. But if he's seating his rounds deep enough to fit in the magazine he's not going to be pushing the bullet into the lands. If it was crimped and hitting the lands then he would likely have chambering issues.

With this not happening with the other upper the converion could be suspect. Maybe not venting pressure quite as quickly as a GI system causing a pressure spike.
You get a quicker gas impulse with a 16 than you do a 20.

Have you checked the headspace? The chamber could be a smidge short.
Have you checked the firing pin protrusion? .028 minimum .036 maximum.

Let us know-I am curious what you find out as I know damn little about re-loading.
To the OP. I never crimp my AR rounds. My brother never crimps his AR rounds. My grandfather, who has been reloading 223 since well before I was born, has never crimped his AR rounds. None of us have had any problems with that. About half the guys reloading 223 crimp, half don't. A lot of people think there will be setback when the round hits the feed ramps in an auto loader. I've gauged dozens of rounds to see if I have had any setback and I haven't.

26 grains of Varget is at max or less than half a grain below max in all of my books. You are loading way too hot for your first rounds through a new rifle. Every rifle is different, you can't expect what works in one to work in another. You ALWAYS need to build your loads up.