guruofhotrod

I've been following the development of the new receivers from Salt Works Rifles - looks like they are getting close to being available, also there is a pic in the CalGuns thread showing their prototype AR15 lower - nice http://www.calguns.net/calgunforum/showthread.php?t=1036853 Their website is still under construction: http://www.saltworksrifles.com/

Here's a link to a We the People, White House petition against the ban: https://petitions.whitehouse.gov/petition/stop-batfe-banning-xm855-ammunition/XrvVh1cj

Quote from ATF doc "When the only readily available handgun that can accept a cartridge containing the projectile is objectively and primarily sporting, it may reasonably be inferred that the likely use of that projectile will also be objectively and primarily sporting. Conversely, when a handgun’s objective design is not limited to primarily sporting purposes, such as handguns designed to be carried and concealed, it may be reasonably inferred that ammunition capable of use in such handguns is unlikely to be used primarily for sporting purposes." So, they are suggesting that AR pistols are designed to be "carried and concealed"? really? perhaps if you are wearing a trench coat! Even with a 7" or 7.5" barrel an AR pistol is a fairly bulky firearm that would be pretty tough to conceal - these guys need to get a little better understanding of what they're trying to regulate.

Hmmmm same as XM855 - 62 grain steel core, nice! Wonder if they'll try to ban these too?

And here comes the gouging : http://www.surplusammo.com/5-56-xm-855-62-grain-penetrator-ss109-lake-city-us-military-50-rounds-in-berry-box/ $1 a round! I never expected these guys to pull this kind of crap! I'm really disappointed !

My exact thoughts on this! To move the position of the gas key, you'd have to move the BCG inside of the upper and then the bolt face would be out of alignment with the barrel extension - I'll have to pick this guy's brain a little more on this one <dontknow>

He was pretty clear about the position of the hole for the gas tube on the front of the upper being inconsistent between manufacturers (vertically) relative to the barrel centerline thus the vertical slot in their adapter. (see pic in previous post) As to the height mismatch we've completely ruled out any possibility of a mixup between high and low profile receivers and handguards/forearms/adapters everything is DPMS high pattern (pre 2009) style - at this point we're looking for a machining or manufacturing discrepancy.

Just spoke with a guy named Tom that handles the manufacturing at Odin Works, He has requested a measurement from the bore center to the top of the picatinny rail on my upper. Had an interesting discussion about the lack of standardization with the 308AR stuff and all the difficulties that arise because of it. As a side note he mentioned that the location of the gas tube in relation to the bore centerline is not consistent with the various manufacturers of the DPMS type 308 stuff requiring them to slot the gas tube hole in the forearm adapter. Got me wondering how they are pulling that off since the gas keys are pretty well standardized and bolt carriers are for the most part interchangeable and furthermore, you can't move the centerline of the BCG in relation to the barrel centerline so how the hell do you move the gas tube position? Hmmmmmm <dontknow>

Thanks FaRKle! Looks like we're all within around +/- .002" of what's expected - not bad! I spoke with Katie @ ODIN Works and sent her an email with the pics and an explanation of the problem, hopefully I get a timely response. Also I mentioned that it is important to get the nomenclature right with the 308 AR platforms - they have references to AR10 on their product page but their forearms (handguards) are made for DPMS type 308's obviously if it were for an Armalite AR10 the barrel nut threads wouldn't mach up. I'll post back as soon as I get a response from ODIN Works

Thanks for the measurements <thumbsup> Looks like my receivers are within .0025" of the expected dimension so I'm seeing this as a screwup on their end - I'll followup tomorrow with an update on how this turns out.

I'm suspecting that the replacement adapter that they sent has the threaded mounting hole (that threads on to the barrel mount boss on the upper) machined about .020" too low resulting in the rail being .020" too high? that's why I'm asking for some additional upper receiver height measurements from you guys that have DPMS type high pattern uppers so that when I get the ODIN guys on the phone there will be no doubt as to what needs to be done for a fix. Thanks Again Here's a pic of the adapter and barrel nut that they provide with their rail system:

The ODIN is the one giving me all the trouble and it's supposed to be made for the DPMS type receivers - I'm going to have to send the pics to them and speak with one of their engineers to try to resolve this. In the meantime if anyone has a high profile DPMS type upper and would be so kind as to take a measurement with a caliper at the location shown here I would really appreciate it :hail:

And the Samson setup:

Here are some pics of the ODIN setup:

That 2.600" expected height is supposed to be 2.060" .0025" higher than I'm measuring - two and one half thousandths of a inch obviously isn't much and shouldn't translate to a .020" mismatch in rail to receiver height - Odin has one rail and uses an adapter with an offset bore to determine receiver height it will align with, I'm wondering if Samson may do something similar on their Star 10 to get it to fit the Armalite AR10 and the High DPMS both since their webpage shows it for an Armalite but I can assure you it fits my High DPMS uppers perfectly http://www.samson-mfg.com/category/308AR_STAR_ARMALITE.html

Ok, I bought an ODIN Works 15.5" 308 Kmod Forend : https://www.odinworks.com/308_KMod_Forends_p/f-15-km-308.htm and specified that I have a high profile pattern upper (ares 308 billet DPMS type) upon receiving the rail I noticed it didn't match the rail height on the receiver properly and the rail wouldn't "clock" correctly - so, I gave them a call and the young lady that I spoke with confirmed to me that they had gotten a run of adapters that were machined incorrectly (the rail mounts to a female threaded adapter that threads on to the upper receiver, has a hole drilled down the length of it for the gas tube and above that hole there is a "key" that engages with the rail to align it to the receiver rail then the barrel nut (with male threads) threads into the open end of the adapter and is torqued to retain the barrel) so she said they would send a replacement. The replacement arrived today and after installing it I'm seeing a rail height mismatch of approx .020"-.022" not much but enough to create an annoyance! Their method of measuring for the height is making me wonder if they got their dimensions wrong, using their method to measure the height I'm getting 2.0575" and they are expecting a height of 2.600" however the handguard is about .020" too high and it's obviously not right - just for the hell of it I installed my newly acquired Samson Star 10 that I put on my other upper on the one having the problem and the rail lined up perfectly(yea, I know the Star 10 is advertised for the Armalite AR10 but with the optional Samson DPMS thread barrel nut it fit like a champ) it was the only thing I had to compare it against - any chance any of you guys with high profile uppers could post a measurement of their upper as specified in odin's instructions so I will have additional info to help identify the remedy to my mismatch. Thanks

That thing is just sic!! Found this on you tube, really nice!!!

They have sent out another email listing it on special $189.95 - great price!

12% off of Orders over $100.00 and Free Shipping on any order over $99.00 http://aeroprecisionusa.com/aspx/store/homepage.aspx?utm_source=Retail+Customers&utm_campaign=3aefa08451-superbowl_sale_013015_RETAIL&utm_medium=email&utm_term=0_fae430ccdc-3aefa08451-192055141&mc_cid=3aefa08451&mc_eid=9943866571

I'm nearing completion of of a couple of builds that have been somewhat long term, they are down to the handguards, I have a High profile 15.5" ODIN on order from a place called MASP Industries (they had a great sale price during the holidays) and also I'm planning on a Samson Star 10 in 9.2" combined with a PRI railed gas block to go on a high profile upper with a 16" mid gassed barrel (the rail on the upper and the rail on the gas block are a match for height, the Samson handguard is scheduled to show up next week - I'll keep everyone posted) The Higher profile ODIN should match with your High profile upper just fine - I don't know how soon the ODIN I ordered will show up since it is on back-order. Some other companies that make handguards for high profile uppers: Aero,SLR Rifleworks, Fortis Mfg, Midwest Industries, Troy Industries, Daniel Defense, Apex, (I will be confirming the Samson Star 10 height, they are advertised to fit Armalite AR10's but they do sell a barrel nut with DPMS thread and so far the measurement from the barrel centerline looks correct - stay tuned! Also I noticed that JD Machine has a new quadrail handguard for high profile DPMS type upper so far in 12" only: http://www.jdmachinetech.com/shop-jd/new-308-quadrail On the BCG Aero has located their Forward Assist similar to the AR15 as a result if you want it to function you will need a BCG that has the notches running down the length for the F/A pawl to engage with - Aero, Shadow Ops and Palmetto offer this feature on their BCG's, (Shadow Ops has them with or without the notches)

I ran across these guys while looking for Go, No Go, and Field Gauges for a 7.62 x 39 build - the have the common AR calibers too (except 300 BLK): http://www.tothtool.com/Gauges_c_11.html

Yea, that's what they've been getting for all the colors, give them a call or keep checking their site for new inventory.

Sorry 'bout the late reply - was helping my neighbor swap on engine out on his '63 Corvair - anyways I popped out a factory DPMS Carbine length action spring and came up with 11-3/8" long and 28 coils, with my DPMS BCG and Carbine buffer combined with a std mil spec AR15 type buffer tube (7") the bolt catch locks on the bolt face no problem - hope that helps http://www.midwayusa.com/product/813595/dpms-buffer-spring-lr-308-carbine?cm_vc=ProductFinding

I'd have to check but, if it's not the CMMG catch (CMMG stuff has a questionable reputation around here) it might be the action spring it is possible you may have received an AR15 spring by mistake - that spring would reach coil bind and could cause the problem you are experiencing, I'll try to find a minute to check the # of coils on one of my DPMS carbine length springs and report back later.

@shibi, can you beat Lanbo's price of $177 and change + $10.00 flat rate shipping?