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FINALLY joining the KAC club - KS-3 & KS-1 (Page 3 of 3)
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Originally Posted By JohnDough: I really think that if KAC meant to make these a slip fit, they would have. They give them the clearances/tolerances they intended to, and KAC tests things more than most. For example, if you look at the notch in your rail/upper where the two join, you will see the gap is wider on the (from shooter's perspective), right side while solid/touching on the left. This is so that the rails line up perfectly as the hand-guard nut is torqued solid. This is the level of detail KAC machines into these rifles. I'd not muck with it with shims and whatnot to alter it. I always assumed it was to avoid tolerance stacking that would cause an upper and lower to not play well together. I’ve been using these shims for as long as I can remember and have yet to have one fail or cause any type of issue. All it’s doing is holding things at one end of the tolerance spectrum, not forcing it beyond where it may be at any point if it wasn’t there. That being said, I take my time fitting these, and every single shimmed upper still allows for the pins to pop out with normal pressure. If I didn’t tell you they were in there, you’d not know it by the “tightness” of the pins, as there isn’t any. Funny enough, I had one KAC upper that was so loose that even with JP oversized pins and a completely unsized shim, it still wobbled 
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@Video @JohnDough You guys weren’t kidding on the BFG ULoop stuff! I’m completely ditching all of my QD stuff after getting a couple of these ULoop / Flatline Fiber sling setups. Really liking it. I’ve got a lot of slings to go through now, lol. I’ve always been back n forth on the rear of the receiver QD cup mounts vs the buttstock mounts and I think I just need to pick one. Seems the buttstock will be the victor. Similarly, on my hunting AR308s, I typically run an end of the front of the handguard QD cup (easier to carry slung behind me) vs all the other ARs are rearmost handguard location for a QD cup. I guess I didn’t realize just how clunky the thick BFG Vickers slings really are, in addition to all of the steel QD stuff, with mixed reliability, too. I’ve got a lot of crap to buy. This forum costs me too much $$$. |
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Originally Posted By Marksman14: I’m a receiver sling guy. Reduces the sling pulling/rubbing when bringing the stock back under my arm for high ready. Those loops look slick. I’ll have to see if there’s a receiver option. Yeah, there’s that. There’s also the sling jacking around with my pistol grip hand AO. It also depends on the gun, to a point. Then with buttstock mount the sling can get caught between the stock and my shoulder instead of wrapping up and over and around my back. We need a poll. I notice an awful lot of people run buttstock for their rear mount via built in QD sockets or add-an-MLOK-QD-socket on the newer Magpul stocks, which I’ve been doing. I know running the rear buttstock mount points the rifle more straight down when not shouldered vs rear receiver mount allows for down, sideways, whatever, however, it also seems to allow the rifle to lean away from the torso vs buttstock sucks it up tight when running outside-side mount. Still a bit torn on this one. It’s been a frustration for a long time, lol. |
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Originally Posted By JohnDough: Light and simple. https://www.ar15.com/media/mediaFiles/453733/1000016910_jpg-3806695.JPG https://www.ar15.com/media/mediaFiles/453733/1000016909_jpg-3806696.JPG How does that stay in there? Without it wanting to push through to the inside? |
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Originally Posted By Brahmzy: How does that stay in there? Without it wanting to push through to the inside? Well, I use the sling, so there is always some tension on it, but if I didn't, the most it could push inward is a few inches because of the glider on the other side you'll note. |
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Originally Posted By JohnDough: Well, I use the sling, so there is always some tension on it, but if I didn't, the most it could push inward is a few inches because of the glider on the other side you'll note. Ah, makes sense - and a pretty freakin great idea. Not to mention saving weight and about $50 per rifle set up this way. QD of any sort is involved, at least on this end. |
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Originally Posted By Brahmzy: Right, with the intent of using an MLOK QD cup or wrapping the sling around using the traditional method. Not threading it through like you did. I just set it up like Magpul shows on their website. https://magpul.com/moe-sl-k-stock-mil-spec.html?mp_global_color=118#tab-content-suggestions Attached File |
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Originally Posted By Brahmzy: Yeah, there’s that. There’s also the sling jacking around with my pistol grip hand AO. It also depends on the gun, to a point. Then with buttstock mount the sling can get caught between the stock and my shoulder instead of wrapping up and over and around my back. We need a poll. I notice an awful lot of people run buttstock for their rear mount via built in QD sockets or add-an-MLOK-QD-socket on the newer Magpul stocks, which I’ve been doing. I know running the rear buttstock mount points the rifle more straight down when not shouldered vs rear receiver mount allows for down, sideways, whatever, however, it also seems to allow the rifle to lean away from the torso vs buttstock sucks it up tight when running outside-side mount. Still a bit torn on this one. It’s been a frustration for a long time, lol. Oh I get that. There’s a reason I pull the KAC receiver sling mount and put something different back there. The QD swivel always finds itself it the worst possible spot with those side mounted ones. |
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This is about the limit of what I can do, it seems. Ammo used is as pictured, LE556TSX. I skipped the energy drinks tonight and shot these at 100 yards, bagged and benched.l using my Coyote rifle ks3 (nightforce nx8 fc-mil). Just got home from a brutal (for me anyway) workout at the gym. It helps focus me. I felt good shooting these. Attached File Attached File Attached File *Yes, it's "zeroed". It just has 0.2mrad adjustments and it do be like that sometimes. |
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Originally Posted By AGR1279: The CRS-3 on my KS-1. I’ve got a FDE ATACR 1-8 on hold which should be great on it. Daniel https://www.ar15.com/media/mediaFiles/17981/IMG_8359-3803103.jpg Can you provide feedback on the CRS-3? How is it working out for you? Can you compare it to the Surefire RC2/RC3 or the HUXWRX Flow series? thanks |
Elite Soviet Democrat
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Originally Posted By themao: Have any of you mount an IR laser to your KS rifle yet? Was curious as to how well the URX 6 limits POI shift. All rails have them of course. Also, any more accuracy tests or feedback is welcomed. It's about the same as my URX4. I am sure there is a delta, but you'd need a lab to see it. |
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CRS-3, MCQ-2 and some others were released from prison yesterday! Attached File Attached File |
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Originally Posted By Brahmzy: CRS-3, MCQ-2 and some others were released from prison yesterday! https://www.ar15.com/media/mediaFiles/50907/IMG_7360_jpeg-3807304.JPG https://www.ar15.com/media/mediaFiles/50907/IMG_7361_jpeg-3807305.JPG IME, the MCQ-2 punches way above its weight for signature reduction, and is actually not bad for sound, but the CRS-3 is just much better. Both significantly reduce recoil and flash and backpressure compared to the 556 QDC. |
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Originally Posted By Brahmzy: Magpul missed a marketing opportunity to convince you you need more accessories when you buy their stocks! BlueForceGear provides detailed instruction better than my technical writing: https://blueforcegear.com/blog/universal-vickers-sling-instructions/?srsltid=AfmBOoptSoJilW-xZJZBaPfhleRsxbgeFXnAVbL-rE4xKYqLrrek4pGh Attached File I'm a sucker for shaving every ounce that is not of benefit. Some weight adds capability, but other weight is just weight for the sake of weight, IMO. This avoids that. To whit, I barely skinnied under my self-imposed weight limit with a fully loaded weapon with Browntip in the mag. Attached File |
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I hear ya on the weight thing. I chase grams on all of my builds where it makes sense and I’m not making compromises on stuff that matters. OTS rifles I’m at the mercy of the manufacturer (which is why I own very few) unless I want to start pulling them apart and swapping parts, which what’s the point. The KAC rifles are GTG as-is except for those awful A2 grips. Not going to mess with a top-tier battle-proven system. Bonus they came with my favorite stock! That said, they’re on the higher end of the scale, lol. The real weight hit though, for me, is moving towards LPVOs and away from the ACOGs. In other news, I’m glad you guys talked me out of pulling off the stock 3-prongs as the KAC suppressor system really looks solid. |
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Originally Posted By Brahmzy: I hear ya on the weight thing. I chase grams on all of my builds where it makes sense and I’m not making compromises on stuff that matters. OTS rifles I’m at the mercy of the manufacturer (which is why I own very few) unless I want to start pulling them apart and swapping parts, which what’s the point. The KAC rifles are GTG as-is except for those awful A2 grips. Not going to mess with a top-tier battle-proven system. Bonus they came with my favorite stock! That said, they’re on the higher end of the scale, lol. The real weight hit though, for me, is moving towards LPVOs and away from the ACOGs. In other news, I’m glad you guys talked me out of pulling off the stock 3-prongs as the KAC suppressor system really looks solid. Yeah, I tried for years to get around the LPVO stack. LED ACOG+P2 G33,45, and Unity 4X + T2 Nothing comes close to an LPVO/P2 stack, and at best, I saved about 10oz, which is kindof a lot, but kindof not. Yes, the KAC line of suppressors is superb. You did yourself a solid in sticking with it. |
 KAC KS3 barrel, Borescoped after Break-In The barrel continues to break in nicely. No notable signs of copper fouling after 45 rounds of 70gr TSX. I clean the bore with a couple passes of a bore brush wetted with G96 Synthetic, and then wet and dry patch it with same. I do not use dedicated cleaners unless there is an issue. My main goal is to remove "junk" and prevent corrosion. |
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Nice ^^ That 70gr TSX stuff is a little tough to find. I’ve only seen one place in stock for $30/box. This KS-1 + AMG + CRS-3 is a heavy sumbish! The KS-3 is more manageable but dayum - not used to such a heavy SBR, lol. I have found the weak link, literally. I need to quit skipping arm day. |
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Originally Posted By Brahmzy: Nice ^^ That 70gr TSX stuff is a little tough to find. I’ve only seen one place in stock for $30/box. This KS-1 + AMG + CRS-3 is a heavy sumbish! The KS-3 is more manageable but dayum - not used to such a heavy SBR, lol. I have found the weak link, literally. I need to quit skipping arm day. I sold several thousand rounds of LE556TSX the other day. 70gr TSX in multiple flavors is easy enough to get, but as you note, expensive. As to arm day, the KS-1 has a super heavy barrel. This is why I went KS3. However, as a guy who has decent lifts, I can tell you that weight is weight, and no-matter how strong you get, heavier is slower. |
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Originally Posted By Brahmzy: Thanks for the reply. I’ve got a reaction rod and Magpul BevBlock I was going to use, but don’t have a KAC-specific one. Is there a reason I have to use a KAC-specific RR? The bolt design is a tad different. I am not sure if the MI RR is Knight compatible. Try check D. Wilson website for tools. I remember seeing a Knight RR or compatible RR for sale. |
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Originally Posted By AR18: The bolt design is a tad different. I am not sure if the MI RR is Knight compatible. Try check D. Wilson website for tools. I remember seeing a Knight RR or compatible RR for sale. I ended up getting the Sun and Shadow KAC reaction rod. |
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Got the KS-3 out to the range today. Holy crap. What an absolutely amazing rifle. I shot it back to back with a bunch of my other rifles and it is an absolute joy to shoot. Very smooth, very flat, very fast. I shot it with both of the new KAC cans and dayum - what a weapon platform. For those saying it’s gassed higher/normally and shoots/behaves like any other std issue rifle, I disagree. If it is, it manages to hide all of that. This thing is like magic. Engineering perfection. I’m a fan and I’m pissed I waited this long to get into KAC rifles. The KS-1 stayed home today - I’ll get it out next time after I get all of the optics on these guns dialed in. Now I’m wanting a KS-2, and a second KS-3, lol. Is KAC ever going to bring back a 300BLK shorty in the KS series? I’d buy one right now. PLEASE make an 8” or 9” 300BLK KS gun. Shit-eating grins here. |
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Originally Posted By JohnDough: A friend if mine has a KS1. He just chronographed some VorTx 70gr tsx. 2670fps at the chrono(10ft?). My Ks3 gets about 2600fps with same. Thats a lot of weight and length for 70fps is all Im saying. Sample sizes of 1 - I wonder if that’s true across all KS-3s and KS-1s…. KS-1 is heavy no doubt! |
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Attached File I shot a 20 round group today, deciding to test 70gr TSX across 4 different loadings. The first 5 rounds was 2018 Browntip, the next 5 was Barnes VorTx, the next 5 was 2009 Browntip, and the last 5 were LE556TSX. The 2018 Browntip and VorTx shot to identical POA, while LE556TSX was 0.1MRAD low and 0.1MRAD right, and the 2009 Browntip had 2 fliers that really skewed the group. I recall it being a bit shoddier shooting in previous tests. Total group size is 3.6", and excluding the flier from the 2009 BT, 2.175". Not bad for 4 different loadings in one group. I filmed the impacts for later analysis, and the 2009 BT was definitely the boat anchor here. *The gun is zeroed for LE556TSX and is zeroed 0.1 MRAD low and 0.1 MRAD right. This is because I am using an NX8 FC-MIL with 0.2MRAD adjustments and I "had to pick". I shifted the zero 0.2mrad left, and fired a 30 round group using LE556TSX. It was...fatiguing. Attached File |
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I’ve always wanted to buy a monster 36x mag scope for the sole purpose of testing precision/accuracy out of any new rifle I build or buy + ammo differences. Thus pretty much removing all human error, doing my part of course. I haven’t, yet, lol. Find the ammo each particular barrel loves the most, according to / aligning to its role and recording that. The things I’d love to do with more time. Again thanks for the time and nice shooting, @johndough (commas matter) |
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Originally Posted By Brahmzy: I’ve always wanted to buy a monster 36x mag scope for the sole purpose of testing precision/accuracy out of any new rifle I build or buy + ammo differences. Thus pretty much removing all human error, doing my part of course. I haven’t, yet, lol. Find the ammo each particular barrel loves the most, according to / aligning to its role and recording that. The things I’d love to do with more time. Again thanks for the time and nice shooting, @johndough (commas matter) I have not felt handicapped with my NX8 FC MIL or my Vortex AMG. With the FC-MIL reticle, I "put the ball in the basket", which is to say, center the dot inside of the 2x2moa gray square that makes up the middle of the target. It fits nicely. All I have to do is center it in this square and let physics take care of the bullets, not aim at a specific atom on the target. I used to use a NXS 1-4. Magnification matters much less than fundamentals. Here is a comparison of two very different systems and approaches: https://www.ar15.com/forums/ar-15/Speer-LE-75-Grain-Gold-Dot-Accuracy-And-Velocity/16-766600/? Attached File Attached File Vs my 1-4x and CHF 16" Gov barrel:  75gr Gold Dot @ 100 yards Attached File Granted, my gun really loved that stuff, but my point is that it's about fundamentals and not that one rifle was fired with 45x magnification and the other with 4x. |
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I didn't run a 30 round group through my other KS3 today (That's fatiguing on another level), but did shoot this decent little 10-shot with LE556TSX. Attached File |
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I suppose I better buy a spare E3.2 bolt for these bad boys, eh? Salad days n all that. Got the KS-3 out again in the mountains shooting steel at 50, 100, 200 and 300 yards with the NX6 over the break and it was a good time. Starting to enjoy the capabilities of quality LPVOs vs my normal ACOGs. Still love a good ACOG but the flexibility of the LPVO is nice. Haven’t quite got used to the weight differences yet, but getting there. |
| Has anyone else had a seized barrel nut on their ks3 uppers that they were sending out to get coated? Kac said it isn’t a warranty claim due to being purchased through a non certified dealer but to replace the barrel nut I was told it would be anywhere from $300-1000 or more for parts if the threads are buggered or they crack the receiver removing the barrel nut or even if they snap the barrel center pin I would have to buy a new barrel as well so parts alone could be up to $1500 does that sound normal for a brand new upper that’s unfired? |
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Originally Posted By Blueboyr1: Has anyone else had a seized barrel nut on their ks3 uppers that they were sending out to get coated? Kac said it isn't a warranty claim due to being purchased through a non certified dealer but to replace the barrel nut I was told it would be anywhere from $300-1000 or more for parts if the threads are buggered or they crack the receiver removing the barrel nut or even if they snap the barrel center pin I would have to buy a new barrel as well so parts alone could be up to $1500 does that sound normal for a brand new upper that's unfired? For what it's worth, if I wanted to cerakote a KS upper, I would just sleeve the barrel with a big sheet of oaktag rolled into a cylinder and spray it without disassembling it. |
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Attached File *Finally* got the NX6 I ordered in January. Had a T2 sitting on the upper before, but never bothered zeroing since I knew this thing needed an LPVO. Might be the first LPVO I actually keep. Still not sold on the MCB furniture, but I had a spare tan SF laying around and it fit. |
FINALLY joining the KAC club - KS-3 & KS-1 (Page 3 of 3)
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