Radioactive

When I was deciding what to build I wanted something capable of 1000 yards. I liked the 6.5 Creedmoor but wanted to be a little different not jumping on the bandwagon didn’t want 300 WM or 338 Lapua. Almost went 6.5 LR Super then flip flopped to 6.5 Grendel since I have several small framed ars. Already have a real nice bolt gun in 243ai so finally decided on 260 rem because I wanted a gasser again to be a little different. Remains to be seen how accurate this will be and was a little down when it wouldn’t cycle. I knew about how finicky the 260 could be in a gas gun and read up some on the different large frame ar platforms. Right now I’m happy it shoots and will see how she really does. I’m going with boron nitride coated bullets and considering using a bipod. I’m not sure how heavy it is but I can say it’s a toad (scale won’t read that high) guessing 13ish lbs thanks all for the help getting it running already got my money’s worth for joining hopefully I can repay in kind

Which do you prefer and why i have both but think I prefer bags - I feel I get to much bounce when using a bipod maybe I don’t do it right

Know you guys have seen rifles and there are many like it but... dpms upper and lower w/ A2 fixed stock geissel 2stage trigger jp 17” hand guard jp hp bolt ergo grip larue 22” barrel rifle +2 gas tube and low profile block sjc brake vortex viper scope, rings, scope level and one piece picatinny mount ambi safety cal 260 remington wish the pics were better

Thinking I’m gonna give boron nitride a go what thoughts are out there? Too big a pain and not worth the effort for the benefit? i have a couple hundred of them all coated up - after I make sure the gun isn’t going to give me any more trouble I’ll start load development with them.

Mags 1 each of p mag, hex, ar stoner, dpms couple boxes of commercial 260 rem just for zeroing, trying mags and getting my new magnetospeed chrono figured out then load development starts...

Meant to type fluted chambers not fluted barrels

Found some stuff on fluted barrels HK figured it out for delayed blowback systems like the 91 It is supposed to help with extraction by allowing some gas to go around the case. This basically suspended the case on a gas cushion not allowing full case expansion thus preventing sticking during extraction. Apparently it works well for thicker military spec brass but has drawbacks and may actually work the other way when thinner commercial brass is used. There has been some internet chatter about ripping cases apart and leaving the top section in the chamber thus allowing next round to acquire a second neck or shoulder. I assume that would stop the bolt from going into battery. Reloading camps are split with some saying case issues and others reporting no problems . Larue went the fluted chamber route in their rifles I assume to aid in extraction and I couldn’t find any real negative consequence reports. Since I purchased my barrel from them that explains the fluting. I’ll run it like it is and maybe go with some Lapua brass or not (already have about 200 or so mixed pieces). I will keep an eye on my reloads and see what happens. anyone have experiences with fluted barrels that can give some insights? is there some info I missed?

I have heard of fluted chambers but had never seen the result i think I remember hearing there could be issues with thin brass being ripped apart not good on any gun but autoloaders more so ill do some research and see what options there are

Thanks all not originally from Alabama but where we call home it helps I’m a redneck so I fit in

Yes but your pics better than mine

Well .081” gas port did the trick locks back on last round - feeds next round eject looks to be about 4 o’clock now to put it all back together with fixed stock and hand guard in place remount the scope and burn through some ammo to see if any little indications show up I did notice slight extracter marks on rim, helical marks on body of the case, primers look good and just a slight ejector smudge on the bottom i have never seen a case body show marks like they do. I assume from chamber needing polished. I’ll attempt to attach a couple pics if not too big

Following this thanks

I’ll let you know the results

Good call on the dowel I have the correct bits. Should I sneak up on the size to see if she’ll run or just go straight to it? I guess worst case adjustable gas block may be required if I get too much gas which is better than it’s running now with not enough. What are you using on your 20” gun?

Didn’t know but suspected as much. Had a suspicion my barrel may have snuck through without the final port size and that’s why I discovered a burr in the port. Was leary about jumping head first into enlarging the port. Thought about sending barrel back but it took so long to get it the first time. What the hell I’ll fix it and learn some stuff in the process. It’s only money if I have to buy new parts cause I screwed it up. is there a simple formula or a pressure chart to look at to figure dwell time /port size etc? I have only been able to find some tables of others measured ports and some of those measurements seem suspect. by the way - thanks

Located in Alabama been shooting and hunting for about 50 years love the outdoors and been a professional guide in the past Been net cruising looking for guidance, suggestions etc and found this place. Looks like a place I can hang out and learn some stuff. maybe I can contribute here and there. I own several small framed ars and other than changing out parts have not built anything from the ground up. I'm on my first large framed build. I decided to try a dpms in 260 Remington for long range target shooting. joined trying to solve a problem I have come up against

Just realized I typed 269 rem in the thread title ... what a dumb a**

Yup read a bunch of his stuff was hoping he could stop by and advise

Carbine or should I say collapsible is 7 inch tube 11 3/8” spring 3.9 oz buffer 2.5” long fixed A2 has 9 5/8” tube 12 5/8” spring and 5.4 oz buffer that is 5 1/4” long those should be Lr 308 compatible 20 rounds is not much but I thought it should at least cycle enough to lock back i don’t have a clue what size gas port is proper for this combo i do know larue did some development with 260 in an ar platform which is one reason I went with their barrel (vs proof research) I’ve also had good customer service from them in the past

Hi all new here and just built a Lr 308 based gun and it won’t cycle properly SPECIFICS: DPms oracle donor gun gen1never fired cal- 260 Remington giessiel 2 stage trigger larue (Walther?) 22” barrel with plus 2 gas system larue low profile gas block and extended tube jp hp bolt sjc brake Stock - carbine and a2 fixed both with appropriate standard buffer, spring and tube 1 standard DPMS mag ammo larue special 130g match grade ISSUE: Won’t lock back on the single round mag test won’t load the next round when attempted locks back manually appears under gassed -slo mo video shows bolt comming back just far enough to eject spent case and recook hammer (approx 2/3 way back) only about 20 rounds fired so far done: cleaned and lubed well, tried both stocks no change, checked gas port and block alignment good, found and removed burr at port no change, gas port measure .069 by measuring pin - called larue and got proprietary info can’t tell you the port size or ammo details they recommended red spring and h2 buffer which didn’t make any sense to me since it won’t cycle the standard stuff have not tried any other ammo don’t have any loaded up yet can’t get factory 260 rem locally knew about the 260 gas gun finikyness going in didn’t expect under gassed symptoms got any suggestions or experience with this? Any info appreciated