Seems to be alot of movement from BCG reciprocation more so than muzzle rise. I did most of my shooting today from a bench rest to see if the Warcomp changed anything in the barrel harmonics or otherwise changed accuracy or precision. To accomplish this I mounted a Nightforce 3.5-15×50 that I had been using last week to do some precision testing on this rifle. The Warcomp changed nothing, and I can report that a Nightforce Uni-Mount will return to zero pretty well even without a torque wrench. Using the glass I could track sight picture disturbance pretty well and noticed much more movement that I would attribute to the BCG than to recoil from the round being fired prior to the bolt unlocking.
Using the same glass on another upper I assembled with a Daniel Defense 18" S2W with a Dreadnaught F2 and adjustable gas block, there is far less sight picture disturbance. However that upper has a fairly well dialed in gas system, and a very aggressive compensator. Thus it shoots much softer between the bigger comp, mid length gas, and adjustable gas block. Even before the adjustable gas block it shot really soft since the gas port size is tuned on that barrel.
After I did my accuracy/precision work, I reinstalled the Aimpoint in the ARMS throw lever mount, and did a little offhand rapid fire. I got called in to work, so only shot 20 rounds, and did so at 100 yards. Unsurprisingly offhand rapid fire at that distance on 100 yard zeroing targets was not exactly spectacular, and not a fair test of the Warcomp. Still it seemed like it wanted to push down and slightly left where the A2 birdcage would walk up and to the right. My unscientific observation here is that I was observing fairly flat muzzle control, and no tendency to climb up and right. Seemed neutral at the shot, but then sight picture becomes disturbed from BCG movement, which looks like a quick jolt to the right as it bottoms out in the buffer tube pushing back on my right shoulder, and a quick leftward and slightly down jolt as it slams back into battery. Keep in mind this is all happening pretty quickly so tracking all of it visually and trying to assign sequence timing is a crap shoot for me. I’ll do more shooting to see what it does at realistic bullet hose distances on larger targets, as well as some formal KD course type stuff like kneeling and prone timed fire/rapid fire.
My only other observations are that my particular 16" Colt M4A1 contour barrel seems to be unremarkable in the precision department. It seems like 10 shot groups at 100 yards want to hover around just under 2" with 55gr FMJ, and about 1.5" to 1.75" with 55gr Nosler ballistic tips. The 77gr Sierra Match King turns in a 10 shot group of right around 1.5" as well, although most of them are in a tight cluster with a few strays. I’m going to re-test all of these loads in brand new brass next time to see if/how much the mixed brass degrades precision.
I’m also sad to say that the Geissele SD3G trigger with this carbine/upper combination can’t be considered safe. With the amount of fore/aft movement this carbine displays, the super short reset on the trigger was giving me some doubles on the bench. While this is entertaining in a juvenile way on a safe range all to myself with a huge berm, it is not acceptable any other time or place. Too bad since it works perfrctly with the 18" bbl upper. So I’ll send it back to Brownell’s in exchange for either the SSA or SSA-E.
I have had doubles on a Geissele Super V before when holding the carbine very lightly to test function. I am more and more becoming a huge fan of the SSA’s.
Exactly my issue. It never manifests itself when shooting off hand, or from a position where I have very positive shoulder pressure and firm grip on the fore end. From the bench though, I am dealing with trying to isolate the rifle from me as possible to reduce variables, so I avoid muscling the weapon. Particularly challenging dealing with the short collapsible stock on the rear bag, if I lean into the butt stock the bag wants to shift forward and it screws up the natural point of aim I just established. So shooting tight groups is a challenge due to equipment issues with the tiny stock and inadequate rear bag. So in concentrating on all that it’s easy to relax and let the shoot loose only to not keep the rifle firmly shouldered and bang-bang!
I guess I should be impressed that more often than not it will hammer both shots close to the same point of impact at 100 yards from a solid position. With the A2 birdcage it doubled a bit too, and strung the second shot out of the main group every time.
I usually just use the magazine as a monopod while seated, and using a T2 and magnifier, typically shoot 2 MOA groups (10-shot) with Ranger Bonded, which is about all that ammo is good for. I have not really tried to shoot any 100 yard groups with better ammo. Have you just tried using the magazine as a monopod and not worrying about all those other things?
Sure, but you usually won’t come close to the potential of the rifle. I have a background in competitive bullseye shooting, and some small bore and high power target rifle as well. So I enjoy trying to get the best out of a firearm.
My other AR or upper depending on how you look at it, with the Daniel Defense barrel is sickeningly accurate with the ammo I tested the Colt barrel with. At least it is considering it is also a 1:7 5.56 NATO chambered barrel. The 77gr MK load can put 10 shots into under 1" when I can do my part.
Been shooting this rifle and muzzle device some more, and let some friends shoot it. I’m liking it more with use than I did at first. Watching two other shooters shoot off hand with the carbine I can see the muzzle stays pretty damn flat, the movement of sight picture is definitely happening on the closing stroke of the action after firing and returning to battery. Not the fault of the Warcomp, just how this carbine is with the stock gas system, and buffer.
The Warcomp doesn’t seem to do anything to mitigate rearward recoil, at least not enough to be noticeable to me. It does control muzzle movement at the shot pretty well, stays pretty neutral no pushing to the left or down from the venting.
I notice no muzzle flash at around dusk, so it seems to live up to claims to reduce flash. As a bonus it also doesn’t seem any more blasty than an A2 birdcage. At least not standing a few feet away even on the right side of the weapon. I can’t and won’t verify that any closer since I personally have no need to. I do notice the tines on the flash hider ring when the bolt closes on an empty chamber, don’t notice it on firing or when loading a round, but I have ear pro on at those times.