starfury

Yeah they have a coating on the brass. It’s necessary for it to feed reliably through the PS90 mags (it is a straight case and it lowers the friction). I clean them with simple green for about 5 to 8 mins in an ultrasonic cleaner (or you can hand shake them in a sealed Tupperware – don’t want to go too long or the ultrasonic cleaner will start taking the coating off too.

I use my Branson ultrasonic cleaner about 90% of the time now and run it 15 to 30 mins (depending on how dirty) using simple green mixed at about 3:1 (I don't use the sonic cleaner heat setting). They come out spotless inside and out and no tumble media in the primer pocket or flash hole.

polished up all my rifle/pistol chambers including my LR308B - here are a few links to my ps90. 930spx & 1894C (dremel with flitz works extremely well). http://www.marlinowners.com/forum/1894/52357-cleaning-1894c-after-shooting-38-specials-few-questions.html http://www.fivesevenforum.com/viewtopic.php?f=19&t=8397 http://www.mossbergowners.com/viewtopic.php?f=14&t=3321

Done!!

here is one of the links discussing it: http://308ar.com/forum/dpms-lr-308-general-technical-discussion/308-ar-weird-casing-marks-after-firing/msg22030/#msg22030

Excellent - glad it is working out!

I dug up a picture of the dents on my cases before and after using the gas block. Some of the dents were really bad before I added the adjustable block; I have an 18” barrel on my DPMS. The scratches on the neck were due to sharp edges on the barrel extension locking lugs (there is another thread here somewhere that discusses that issue).

Had the same issue with my DPMS 308 producing good dents at the mid-section on cases and landing in the 2 to 4 o'clock position. I didn’t like the banged up cases since I was reloading. The stock rifle is over-gassed so I added an adjustable gas block (JP rifles) and opened it up from essentially closed at ¼ turn or so intervals until I found good extraction (with only very slight marks) and then gave it another ¼ turn. Put some loctite on it and that was a couple years/1000+ rds ago and it has been working like a champ.

Be extremely careful if it is stainless steel (barrel & comp). Stainless isn’t forgiving like steel, when you start to bind it (i.e. makes noise’s or you feel it crunching) –it is starting to gall and if you go much further it will completely lock up and you are out of luck. Galling is the local roughing of the surface/forming of protrusion between the sliding surfaces and stainless steel is very bad for it. Survivalshop is correct – use a tap/die to clean up the threads if necessary (you can also use a wire brush on a dremel at low to moderate speed to clean them up if loose material is present). Then use just a touch of high temperature anti-seize to keep it from galling and make it easier to spin on/off. High temperatures combined with tight threads on stainless steel is a bad thing without a little anti-seize (we have had to cut off numerous stainless bolts of all sizes at work when folks forget to put a little moly based anti-seize on them).

I have a DPMS LR308 - just measured the pins with a caliper and they look like they are 0.277" diameter. If you need any other dimensions just ask!

Had the same issue with mine - the marks are coming from the sharp edges of the barrel locking lugs. When the case is extracted it drags against the ejection side (since the extractor is putting pressure on only one side of the case) – this is normal. You can see this if you load a resized piece of brass (or snap cap) into the rifle and then slowly pull back on the charging handle while looking into the ejection port. The edges of the lugs were very sharp on my new dpms lr308 (could really feel it with your finger). I used a dremel tool and a polishing wheel (with a little jewels rouge) to dull them just a little along with polishing up the chamber. You only have to do the two lugs on the extraction side. Cleared up the marks on mine immediately. Edit* I found this old picture that shows the marks on the necks (before I touched up the lugs).

I have one of these SWFA 3-9x42's on my AR10 and I love it. It is a solid top notch scope! Have about 400 rds through it and no shift in zero. I have it in an AD-RECON-30 mount - which is ok, but if I had to do it over I would get the LaRue mount. The AD mount tightening method leaves it either too tight or too loose between settings. http://swfa.com/SWFA-SS-3-9x42-Tactical-30mm-Riflescope-P50716.aspx http://swfa.com/SWFA-SS-3-9x42-Tactical-30mm-Riflescope-P41044.aspx Check their sample list for riflescopes: http://www.samplelist.com/ You can get the swfa 3-9 about $100 cheaper when they show up from time to time. I have bought a Trijicon TX30 and an aimpoint CompM3 demo B's through there and both are great.

I have a RRA 458 socom upper on an YHM lower with a Trijicon TR24R on top. I absolutely love the rifle and it is a sledge hammer. You really need to be a reloader to shoot it cheaply and I typically fire bullets ranging from 250gr to 500gr through it (Rem has bulk 300grHP and 405grSP that I reload for my plinking). You need to check out the website: http://458socomforums.com/ for all your answers. The reason I went with the socom over the Beowulf are 1) much larger bullet selection, 2) it headspaces off the shoulder, 3) no modifications require to the mag.

I've got the adjustable JP gas block over a year ago and haven't had an issue with dented case necks. I had it gassed to hot to begin with and then cranked it down essentially shut-off (would not extract) then opened it up to about 3/4 of a turn and adjusted in 1/8 turn intervals until I got it to extract consistently. I think it was like 1-1/8 turn or so. I then used loctite (blue) to stiffen it so it wouldn’t move and it has held just fine for several hundred rounds. I think I can see about 1.5 threads on the set screw the way it is set (I could post a picture if needed). You might want to check your seating and and maybe look inside the tube to see how far the set screw is extending.