98Z5V

This is the mini chop saw that I use to cut down .223/5.56 brass; picked it up for about $25 at Harbor Freight: This is my preferred VLD chamfer tool - Lyman Case Prep Multi Tool, available all over the place...

It would be a PITA to split that topic, etc., however... I can post it again in this thread, and then the whole thread can be moved/pinned in the Reloading Section.

I did see that - I've never used that stuff so I'll have to check into it more. I've heard of people stating to use red Loc-Tite installing barrels (Loc-Tite 271 permanent thread locker) and that's not a wise move... EDIT - This might be worth trying... Loctite ® 609™ Retaining Compound, Cylindrical bonding Loctite ® 609™ is a low viscosity, rapid-curing anaerobic adhesive that augments the strength of press fit assemblies or slip fit assemblies up to 0.005"in diameter. Adds up to 3,000 psi holding power. Recommended for parts that will need subsequent dismantling, i.e., retention of bearings onto shafts and into housings. Technical Data: Typical applications: Augment press fits Viscosity: 125cP Cure Time: Fixture - 10 minutes Full - 24 hours Max gap fill: 0.12mm Temperature resistance: 150°C Shear strength: 15.8 /mm2

kiwi, that was incredibly cool, man.

This is good stuff. Thank you Criterion. Oh, and ss!

I'd suspect this, first - with a tight chamber. Got a GB link to the same barrel for sale? Maybe we can check that out. It's not a problem with the upper receiver - AP makes a good, reputable product. Still needs to be inspected, though. It's not the BCG - Toolcraft makes a great BCG,and they are the provider for ALOT of boutique-brand 5.56 BCGs. They've been at this game for a long time, and do the 5.56 mil-spec BCG right. However, you mentioned that this is a mil-spec BCG in your 308. Just so you know, there is no mil-spec for 308ARs. Just isn't one. Doesn't exist. Toolcraft probably makes their 308 BCGs to the same specifications as the 5.56 BCGs, though. Now, all that said, BCG still needs to be inspected, even though BCGs aren't commonly responsible for this type of malfunction... That barrel, man... I keep going back to that unknown GB barrel... and it's probably got a tight chamber...

Indeed...

If I wanted a UBR on a Big AR, I'd run the UBR 2, which is 7 5/8" internal depth - and I'd load it with Armalite AR-10 Carbine buffer and spring...

@survivalshop, hey brother - this is just ANOTHER reason I just run the Armalite AR-10 Carbine recoil system on collapsible stock Big ARs, and I don't have to fuk with it...

Just trying to help here, please don't think I'm being a dick. Info is everything, and it's been general thus far, considering all the options with this JP stuff. Just so you know, one of my mottos is: Don't complicate shiit with complicated shiit. The JP-anything is complicated shiit...

Dear Sweet Baby Jesus, they have 4 different flavors of the SCS for an "AR-10," as they state... Which one of those things do you have?

I'm seeing 6 different JP Full Mass carriers - which one do you have, specifically, by part number? Just trying to figure shiit out here.

I just HAD to step in there and fix that. Just HAD to!...

Need more details on these two things, spwcifically. Well, all three. The UBR is a carbine-stock setup,with it's own built-in AR15 Carbine-lengthed receiver extension, with an internal depth of 7.000". - You sure those parts are compatible? Before I go look up the JP stuff?

By the way, there's a Metric Shiit-Ton of measurement data in this table. I'm just sayin'... My Metric Shiit-Ton exactly equates to SS's Bazillion. Plus 1. Click it, and it get's bigger...

^^^ That right there, SS?... THAT is the reason that the AR-10 Carbine recoil system is superior in a 308AR, if you plan on running a collapsible stock. You know why, brother? Vendors can't fuk it up. You order (real) AR-10 parts, and you get REAL AR-10 parts, that just work. For that reason only, it's far superior in a large frame AR carbine recoil system.

That a 39-coil spring, and it looks to be just short of 11", so that's an AR15 Carbine spring, and a weak one at that, because it's relaxed length should be 11.25" long. Could be camera angle, but that spring isn't 11.25" long - doesn't matter, because that spring will have your BCG body slamming into the back of your upper receiver. The buffer looks like a DPMS-based LR308 carbine buffer - looks like it's 2.5" long. Okay, so that's a mix-match of Carbine recoil system parts (308 in one, AR15 the other), but attempting to run a 308 gun in a rifle-length receiver extension. That will jack your lower receiver all up, possibly with permanent damage to it, just from firing it like that. That A1 rifle-length receiver extension is okay with that stock - you might want to check and see if that stock needs the "A2-length" recoil system. If it does, you need the 5/8" spacer for it, and the longer vented screw. Next, you need a DPMS-based LR308 rifle buffer, and it should be 5.200" long. If you get a rifle buffer that's for an AR15, it will be 5.900" long, and it won't work in your 308 - it will be short-stroking, because the BCG can't travel far enough. So, LR308 OR AR-10 rifle buffer is needed - they're both 5.200" long. Next, you need a DPMS-based LR308 Rifle buffer spring, OR the AR-10 Rifle buffer spring. Both will work in that rifle receiver extension. If it's an AR-10 rifle buffer spring, then it's gonna have the relaxed length of 13.75", have 34 coils, and the wire diameter is gonna be 0.072". Armalite uses the exact same spring in the AR-10 rifles and AR-10 Carbines. It's got an Armalite part number of EA1095. If your stock body requires the "A2 length," then you need these two additional parts, right here:

On that note, there's that many manufacturers that think they can get it right - and they don't always. Wrong buffer spring, buffer that's 0.050" too long, receiver extension that 0.100" too deep... and your recoil system is jacked and not working right. There's only one manufacturer for the parts I listed, and I've never heard of them getting it wrong on that recoil system. I'm just sayin'...

5.56 info here- Ballistic Advantage .223 Wylde SPR barrel: 18" .223 Wylde SPR Stainless Steel Rifle Length AR 15 Barrel w/ Ops 12, Premium Series, 1:8" twist Gas port diameter: 0.095"

You can run the Armalite AR-10 Carbine recoil system on a DPMS-based 308. I'm doing it on 3 of them.

Great news, Pete! Get out and test fire that beast, and let us know how it goes. Test the last-round hold open first - load 1 in the mag and fire, make sure the bolt locks back. Good stuff!...

There is no wonder that the guy was selling this - because it just didn't work...

MOST Factory loaded 150gr ammo is moving too slow from a .308AR with a 1:10" twist barrel. You gotta crank the speed up on the 150s to make them work in a 308AR with a 1:10" twist. I reload Hornady 150gr FMJ-BT projectiles ALOT, in .308 Win and 300BLK - hell, it's all I load for Blackout. For the .308 Win, crank up the powder charge, with the right powder, and those specific 150s work like a charm through a 1:10" twist. I've got some 150s loaded for bolt gun only (Rem 700 AAC-SD gun), that wouldn't be "safe" in every semi 308AR.

That info right there solidifies one thing - R25s are straightup DPMS patterned rifles; hell, they ARE DPMS rifles. PSA handguard threading is DPMS handguard threading. Welcome aboard, man - brace yourself for PSA questions...

Measurements, measurements, measurements... That's what it comes down to with these things. Buffer lengths (both carbine are rifle) are different than AR15 parts. Buffer springs are different than AR15 parts, in both relaxed length, coil count, and wire diameter. Rifle receiver extensions are all the same. There is zero difference in a rifle receiver extension, in construction, even though you'll find "A1 and A2" extensions. An A2 extension is nothing more than a 5/8" spacer on the end of an A1 extension, with a longer vented screw (upper screw). Well, and the longer A2 stock that covers it all. Rifle receiver extensions are all the same - extra parts for the A2 stuff to make it 5/8" longer in the stock body. Carbine receiver extensions have two flavors - standard AR15 carbine receiver extensions fit on 308s. They just use a 308AR shortass carbine buffer and a different spring (than an AR15). This is because the bolt carrier is longer in a 308. Shorter buffer, longer bolt carrier, has to fit into the same space... AR15 carbine receiver extensions have an internal depth of 7.000". Armalite went about it different in the AR-10 Carbine - they made a longer AR-10 Carbine receiver extension, and the internal depth on that is 7 5/8". It uses the Armalite EA1095 buffer spring (same spring for both rifle and carbine recoil systems in the AR-10, the EA1095). It uses standard AR15-lengthed carbine buffers, in the H3 weight. This is a better carbine recoil system for 308ARs. Here's the tech data on recoil systems - spring lengths, coil counts, wire diameters, buffer lengths... this is THE authority on recoil systems... http://heavybuffers.com/reference.html