merrymarksman

An earthquake I'm guessing. No other explanation comes to mind 😉 Seriously though, now I'm gonna get to welding a frame and some nice swinging steel targets together so i can take this out to 300, 400 and 500m. I have measured muzzle velocities and fed it all into strelok, but checking if the calculations hold up to reality is a MUST imo, when you're planning on shooting game. probably never going to pass 400m shooting live targets, that's pretty much my limit on ethical hunting. 500 is only for good measure and fun of course 😄

The flyer was totally my fault btw 😅

Thanks guys, appreciate your support! Best thing is, it doesn't only run smooth as hell, it also holds really nice groups. That's 5 shots magtech 150grs FMJ @100m, and then zeroing my red dot @50m with 2 shots between clicks 🤗

Sooo, my rifle finally found its way back to me 😊 thought I'd give you guys a quick update: barrel's been cut to 18" and threaded again. For testing I ran some 30 rounds of the ammo that gave me the issues with blown out primers and whatnot. Same as before, every third primer blown, cases pretty scratched and beat up, so my take is these are just poorly manufactured with tolerances way bigger than the chamber of the gun allows. Not going to use this ammo again. But then I grabbed some Magtech FMJ 150gr, Federal Trophy Copper 150gr and 165gr, Federal Gold Match 168gr, Barnes TTSX 130gr, 150gr, 168gr... All these cartridges worked without any of the problems mentioned above! With the rifle suppressed and the Heavy Buffer CAR-10 that is. My gas port setting had to be changed of course, now it's perfect when the screw is at a quarter turn for supressed and about 1.25 turns when running a muzzle brake. The rifle runs like a charm now, once I had the gas block dialed in no issues whatsoever the first 150 rounds i put through that thing, switched through all the ammo types I mentioned like a maniac, not caring for groups only testing the gas system. I actually loaded a mix of 130gr, 150s and 168s in one magazine in no particular order to see if there would be any FTEs or FTCs with the gas block setting I dialed in on, but nothing. Smooth sailing, no matter what I fed the rifle 😄 I'm really glad that turned out so well! Also it's looking like a beast now, the seamless transition from handguard to supressor really adds to the look and the balance of the gun as well.

Oh alright, I thought there were some kind of manufacturer-standards which they would stick to 🤔 well anyway I'm going to wait with anything gas system related till after the barrel's been cut down and then see what the gun does with the gas block fully opened and the 5.5oz buffer in there. I actually measured the gas block diameter before ordering the adjustable one, it's 0.75", cause I wouldn't want to buy parts that won't fit my rifle 😜 (don't know why I didn't stick to that, considering the kyntec buffer 😅😅) Anyway I'm pretty excited about that next step, I'm expecting the whole setup to become even more compact and maneuverable than it is already. Pretty mindblowing to have the whole capacity of a .308 in a package that looks more and more like a AR15 MSR/DMR or something. And it reliably produces sub-MOA groups, with decent (factory) ammo even half MOA all day long. I'm in love with this thing! 😄 Also I ordered some stuff that's more on the handling related side, Radian Charging handle and Ambi short throw safety as well as a Magpul Ambi bolt Release, just for the hell of it. I'm starting to run out of ideas on what else might need some tweaking 😆 Input is kindly appreciated 😏

It's a 20" barrel with rifle length gas system Regarding the gas port size I found this chart in another thread: DPMS LR-308 Style Rifle 18" rifle 0.308 0.0960 18" car 0.308 0.0635 16" mid 0.308 0.078 16" mid 0.308 0.081 16" car 0.308 0.07 16" car 0.308 0.073 16" car 0.308 0.076 20" rifle 0.308 0.0935 20" rifle 0.308 0.096 So I'm assuming it's either 0.0935" or 0.096". That's on the wider end of rifle length gas ports, so I'm not exactly comfortable with the idea of drilling that out even further. From what I'm experiencing now, with the gun running with the gas block nearly fully closed in both suppressed and unsuppressed configuration I'd expect it to be still in the operational range with the barrel cut down and the gas block opened up a bit.

I was hoping to be able to make up for the loss of pressure by opening the adjustable gas block. Do you think that that won't be enough? And I went ahead and ordered a CAR-10 5.5oz Carbine 2.5" Buffer along with a Radian DPMS 308 Ambi Charging handle. I'll let you know how the rifle runs as soon as I dropped those in 😁 (2-3 weeks delivery time though 😢😉) Thanks again for your advice!

What i meant was that the DPMS Gen II BCG is smaller and lighter than a LR308 BCG to fit these small frame 308 ARs, isn't it?

First off, thank you all for the immediate and precise answers! 98, jt, rex, Doc 👍 As you said I'm pretty sure my buffer is nowhere near 5,4oz, could't find any specs on it though and haven't had the chance to weigh it Headspace never seemed to be a problem, I had some ejector marks every now and then, but never flattened case heads, must be the ammo. Also my thinking was overly light buffer equals fast travelling BCG (especially since its a trimmed down DPMS 308 BCG) which might jam the cases in the chamber way too hard... Is that a thing or am I making stuff up? I'm defenitely gonna follow your advice and get me a CAR buffer to go with the heavy buffer spring I got already, I'm leaning towards the XH since I'm running the suppressor more often than not. One thing that i forgot to mention that led me to believe it could be gas related is that the charging handle actually came loose and creeped towards my face after 2 or 3 shots, which is pretty annoying when you're dialed in and trying to print some tight groups. Any thoughts on that? Also I'm planning on having the barrel cut down from 20" to 18" , that should decrease dwell time and overall pressure on the system, right? I'm just not sure whether that's gonna be a noticable difference.

So, as you can tell I just recently signed up here. I'm from Germany, and after I got my hands on the H&K MR308 while in the army decided to buy a Remington R25 GII soon as i heard of it. I wanted a .308 in a slim and lightweight package since said H&K was far too bulky and heavy for hunting, what is the main purpose of my rifle (also it was way too expensive). Anyway, I bought the gun in 2016, got a suppressor in 2017 and therefor had to make the first upgrades, muzzle threading and an adjustable gas block. But ever since the gas block was changed I had to turn the "gas screw" pretty much all the way down when running the rifle suppressed and about 1 turn further out when unsuppressed. That wasn't actually a problem, it ran reliably with all sorts of ammo once i figured out the right setting. Trouble started when I decided that I wanted a collapsible stock, bought a mil-spec AR-15 7" FAB-Defense Reciever Extension and a Kyntec .308 Shorty Buffer (https://www.kyntec.com/product/rb5004-kynshot-marksman-recoil-buffer-.308-shorty-collapsible-stock-2.5-inches-6/) as well as a Heavy Buffer Carbine .308 spring (http://heavybuffers.com/springs.html). I really thought i had perfected my setup, but when I took the rifle to the range for the first rounds after these upgrades weird stuff started happening: First off, it absolutely demolished the brass, leaving deep marks of the double ejectors and blowing out 8 primers of about 40 rounds. I also had to turn the gas screw even further in to reach 3-o'clock ejection, somewhere between a 1/4 to a 3/8 turn from complete lockdown/single fire. After reading a bunch of threads on gas system and recoil system topics I realized that my rifle is most likely under-recoiled or over-gassed respectively. I'm pretty clueless on how to solve this in the most efficient way and I don't have an experienced gunsmith with deep knowledge on the AR10 platform on hand so I'm turning to you guys for advice. Now, I know this issue has been adressed a hundred times on here, I just can't figure out what's the proper solution in my case. So I'm hoping someone will have the patience to break it down for me again 🤔 Would a CAR-10, or maybe a CAR-10 XH, be able to solve this problem or do you think the issue might be the gas block (i.e. poor fitting of the gas block on the gas port by the gunsmith?) ? Or would you simply say I'm running a setup that's doomed to fail and that I should put the factory recoil system back on the rifle and be done with it? I'd be really grateful for any input!