On Thursday, the .458 SOCOM upper that I ordered from Teppo Jutsu through the Group Buy on EE arrived:
My configuration is:
A3 flat top (DPMS Lo Pro)
Aluminum Free Float Handguard (DPMS)
Low Profile Gas Block
16 inch Lothar Walther stainless steel barrel
A1 Birdcage flash hider
OKO 4M Red dot
RRA lower
The ammo that I was using was Corbon 300 grain hollow points.
First off, I am throughly impressed with the accuracy of this thing. This was 8 rounds that I fired after sighting it in at 50 yards (indoor range). At that distance, the center of the target is barely bigger than the dot on my sight, and I'm no "William Tell". I'd say that this is pretty good!
I was also very pleased with the way this gun handles. I actually got nervous before I fired my first shot (I'm a recoil wimp), but I was pleasantly surprised to find that the recoil wasn't very hard at all.
On the other side, I did experience a few malfunctions. I only fired 20 rounds. Of those 20 rounds, I had 2 "jams" where the round didn't feed all the way into the chamber. This could have been caused by 2 things. First, the ammo that I was using was Corbon 300 grain hollow points. They could have gotten hung up on the grooves for the locking nuts. Also, the mag that I was using was a new SA80 mag that I have only used once with 5.56 ammo. It seems to be a little on the sticky side.
I also had a couple of instances where the bolt did not move all the way forward. I was able to resolve this by pulling back and releasing the charging handle.
When I got home I loaded up my Bushmaster 10 round (5.56 10 round, .458 SOCOM 4 round). WITH THE FIRING PIN REMOVED, I pulled back and released the changing handle to chamber and eject all 4 rounds. I did this 3 times without incident. I'm going to take it back to the range tomorrow and give it another try.
I'll update after I get back from the range tomorrow.