top of page

77gr Sierra Match King (OTM) by Gorilla Ammunition

Gorilla Ammunition is something I just came across a short time ago. While building my precision AR-15 I went looking for some well priced match ammunition. The 77gr Sierra Match King (OTM) is one of the most popular ammunitions for precision in .223/5.56 caliber. Knowing that there would be extensive testing after the rifle was built I went ahead and got some of this Gorilla Ammunition 77gr Sierra Match King ammunition for this testing. When it arrived I was really impressed with the packaging, it was very tight and in really awesome plastic holders inside the boxes. When I took the ammo out it was well put together, nothing to the naked eye stood out. It was well crafted. I have to say I never had heard of Gorilla Ammunition prior and I was impressed to say the least. The next step was to hit the range and see how consistent their ammunition performed. The thing with match ammunition is consistency. When you look at regular ball ammunition it is not stringently held to the same standards as match. For instance the amount of powder in the cartridge could vary in ball more than in match grade ammunition. This affects the consistency in which the round performs. Having a larger range of the amount of powder means a larger performance range for the round. Simply put for example, with ball ammunition your rifle is 1 MOA to 1.5 MOA and with match ammunition it is sub MOA to 1 MOA. So how did this Gorilla Ammunition perform?

Upon the first trip to the range we sighted in the precision AR-15 build (SPR/DMR) we completed. Doing so we used the Gorilla Ammunition and immediately we saw tight groups. After being sighted in we moved onto really testing the ammunition out. I am not an expert or even an advanced long range shooter. We used the standard 100 yard range for this testing. There is so much to compare and most anyone can find a 100 yard range. So upon really challenging the Gorilla Ammunition 77gr Sierra Match King (OTM) we immediately saw a grouping of .70" when my buddy Nate Murr (Inventor of the GripStop) was behind the rifle. When I got behind the rifle my best group was .92". We used three (3) round groups for our testing and it was 83 degrees outside with high humidity. Given that Murr is apart of the scout sniper community you can see that his groups were much tighter than mine and he really is able to push the ammunition more so than I. The first range trip was successful and we had nothing in terms of issues with the ammunition. We fired around 150-200 rounds in this trip. I went home, cleaned and lubed the gun. Applied Loctite to the hardware as we ran the gun with no issues on this first range trip. So now it was back to the range to see if I could replicate and even improve on my .92" three round group and to finish testing the ammunition.

Indeed on my next trip I replicated over and over again my .92" groups and even hit a .65" group on a zombie target at 100 yards (picture above). In fact through the 300 rounds after the barrel was broke in my average is .91"-.94" for a three shot group at 100 yards. Now where I found the Gorilla Ammunition to shine was its consistency. More specifically the standard deviation between groups. I found that through the bazillion groups I put down range that the standard deviation between these groups was .17". With Black Hills 77gr OTM my standard deviation is .14", which tells me Gorilla Ammunition is right on par with Black Hills in terms of consistency. If you know about Black Hills you know that their reputation is consistency. That says a lot to me about what kind of ammunition Gorilla Ammunition is putting out. The only downside is the slight bump in price compared to Black Hills. Gorilla 77gr SMK will run you $25 for 20 rounds while Black Hills 77gr OTM will run you $54 for 50 rounds. So you are looking at about 15 cents a round difference. Not horrible, especially if Black Hills is sold out or another major manufacture. But you should really look at what Gorilla Ammunition is putting out, it certainly is worth you time. I do not think you will be disappointed as I have not been.

Featured Posts
Recent Posts
bottom of page