Greetings all, I normally don't post these kind of things but today was something special so I just had to share.
I've had my Sig556 for just over 2 years now and have never really been completely impressed by it. Don't get me wrong, the gas piston design is nice, as is the nitrated barrel, and the AK like internals that just run and run and run... but no matter how hard I "tried" I never could get in under 5" at 100 yards the range. After lurking around here and over at sigarms556 I decided to try and find "the magic bullet." Every one here knows what I'm talking about but those who are new to the rifle platform and lurking themselves "the magic bullet" is the perfect bullet weight matched to your rifle's barrel twist. My first go was a total bust. It was 98* in the hot Georgia sun and I succumbed to the heat long before I actually gave up. My results were... poor and that is a generous statement at best.
Fast forward to today, I got off work early and figured I'd give "the search for the magic bullet" another go. Weather was a nice 87* with a slight constant breeze coming right to left across the field. Since I just recently picked up a MSAR STG with an ACOG 4x scope I figured this would be a perfect time to sight that gun in as well. I'll just say that if you ever have the chance to shoot one of these they are so much fun and so well balanced that they will put a smile on your face after just a few rounds.
Anywhoo after the STG was good to go put my Sig on my newly acquired Lead Sled and loaded some 55gr m193 mil surplus in my 30rd mags to try and confirm that I still had zero. The Lead Sled was a HUGE pain in my ass simply because with a 30rd mag inserted the rifle just didn't fit properly in the sled. I didn't have anything else so I had to load one round at a time... for every shot. Lesson 1 here is make sure you have 10rd mags if your gona do this kind of experiment. Everything said and done I was expecting it to be a little off since it was still zeroed at the 100yd line from last time but holy cow was I surprised at what was happening. Lets just say a picture is worth a thousand words.
I made sure my shooting style was consistent between each shot and I must have shot 5 targets all looking just like that picture before I got frustrated and replaced the CenterPoint for the ACOG from the STG. It took a while to re-zero the ACOG but once I did I was shooting much tighter groups. Figured it was good enough and went to the 100 line.
It was getting dark fast so I didn't have time to test every ammo type in my bag but the pics speak for themselves. I did 5 shot groups so the numbers gave more of an accurate representation of what each weight is capable of. But in the spirit of the true internet commando I had to give the best 3 shot spread in the stats.... just because
Here are the results:
The focchi 5 shot group
Black hills 77gr on the left and 69gr Federal Sierra Matchking on the right
40gr Foccii 1.06" .375" (had a keyhole)
55gr M193 5.5" 2.75" <––––––- What I had always been using since day 1
60gr TAP 2.88" 1.375"
62gr American Tac 1.75" 1.25" (best for plinking)
68gr Black Hills 4.5" 1.75"
69gr Fed Sierra match 2.0" .875"
77gr Black Hills 1.75" .375 (tightest 4shot group)
I would love to see this done with a nice 12 or 16x scope and I'm kicking myself for not testing the other weights I have... but right now I'm going to have to give the edge to the 77gr Black Hills. Pick a box up and try it out for yourself and let me know how it goes.
Morals of the story is:
Sometimes 10 round mags are useful
Don't buy junk scopes
Don't wonder why your groupings stink with crappy ammo!
First time doing this so comments or criticisms welcome