98Z5V

It's not at all "complicated" to me, in the least. I understand all of it, completely. I just build these things based on what I know, and have learned, then run the gun. I don't have functional issues with my builds. I use my own combination of recoil system parts, I check the gas tube length, and I measure the gas port diameter. If anything is off with the gas tube length, I fix that. If anything is off with the gas port diameter in the barrel - I drill it. My recoil system never fails me (now), not once, ever (after I learned why the first one was completely FUBAR'd and jacked-the-fuk-up - FROM a reputable manufacturer). I build functional guns, and they run, right out of the gate, everytime. That's only based on learning that there are manufacturers out there that don't know what it takes to make a "functional gun." My first rodeo with a carbine recoil system was my last - I dove head-deep into learning WHY it fucked up, and got hip-deep into recoil systems. At that point, I had my own answers, and never looked back. You stated yourself that it ran before. You need to look at what you changed, to make it into a non-functional rifle...

How is she assembling guns, like this?... 😁

You never, ever need "a bigger safe." You just need "another safe." It's as simple as that.

Your gun ran fine with a rifle-length buffer and spring, before, and the issues have cropped up now? Start with a buffer weight of 5.4oz, and see where you go from there. H2 weight is 4.6oz. JP Rifles are awesome at race-gun shiit. Are you trying to build a competitive race-gun - or an operational gun?... Start with an operational gun, then do what you want, piece by piece. I'm here to help you, not battle you. Your gun doesn't work right now. I'm trying to get your gun to work, then you can experiment. Comprende?...

Faxon has a limited edition run of Titanium Nitride PVD coated barrels out now. They're GOLD. Check it: https://faxonfirearms.com/rifle-barrels/limited-edition/?_ke=eyJrbF9lbWFpbCI6ICJyZ3JoYXJ0bGV5QGhvdG1haWwuY29tIiwgImtsX2NvbXBhbnlfaWQiOiAiS2pSUWl1In0%3D @MikedaddyH needs one of these, for a very specific gun!...

Start this in it's own thread, instead of tagging a reply to a thread that last saw life on 4 May 2013. Kudos for the reasearch, big time, but your question stands alone. Start a new thread, guy. Brand new. Only your question.

In a very, very minimal way... by the way...

The problemwon't be your ToolCraft BCG. These guys you bought the upper from ONLY deal in blem parts, ONLY. That's all they do, and they get them cheap, mark them up a little, and make money that way - that's why you got it so cheap. Question is - what's the "blem." Is it a cosmetic blem, or a functional blem?... You never, ever know, with them, until it's in your hands and you inspect it... I've warned people here about that company before. A little bit of research will show it. Always dig into any company that looks like it has prices "that are too good to be true." There's a reason. Click this link: https://forum.308ar.com/search/?q="Davidson Defense"&updated_after=any&sortby=relevancy

I stopped after your first sentence. ^^^ That thing above is literally, your first sentence... First, don't complicate shiit with complicated shiit. You did. The easiest wayto figure this all out is to buy a cheap Armalite AR-10 Rifle Receiver Extension kit, install it, and see if your gun functions. You've gone way overboard with this JP SCS and a spacer to make it fit, playing with weights, all that. Start from the basics and get a running gun, first. Once you have a running gun, go wild, and add as much complicated shiit as you want - one complicated part at a time, so you know what fails and doesn't work.

That is not a "Double Feed." A true Double Feed is only a magazine problem, forever and a day, Amen. A true Double Feed is two live rounds trying to enter the chamber at the same time - and that's the magazine's fault (either feed lips or spring pressure). Nothing else on this planet can cause a true Double Feed. Think about the name - you're double-feeding, two live rounds. The problem you have is a Failure to Eject.

We all learn from each other, man. Sometimes, the hard way...

I like those shirts...

Just add the Strike Industries LINK rails that you need, and be done...

Why not just dispense with the headache, and add a few of these? Strike Industries LINK rail sections - they developed a rail section that mounts to Key-Mod and M-LOK. I have 3 or 4 or these things, and they work. Save yourself the headache, man. https://www.strikeindustries.com/shop/products/rifle-accessories/ar-9/link-rail-section-7-slots-qd-featured-patent-pending.html

That will take alot of work, right there. I'm just sayin'...

These are the answer... Just ask @Rsquared...

You're about to get ALOT of math on that platform. It's gonna hurt, there's gonna be so much. It's gonna hurt worse for alot more people out there, though. That's the way it needed to be, though... Just wait for it...

What gets me is this thing is a gimmick - it's a solution, looking for a problem. I've heard about it for years, but I've never even looked into them before @jtallen83 posted that link, and there was an animation in there on what it does. It offers no benefit, in any way... That's my $0.02 on the thing. If the roller was on the body of the cam pin ( I thought it was) it would smooth the locking and unlocking of the bolt, into the extension, and reduce the need to "slide" in the BCG body.. This thing doesn't do anything but (possibly) roll up the left side of the receiver when the bolt is under zero pressure.

That's just a radius cut in the gas key body. This roller cam pin looks like a waste - I always thought the roller was in the stem, so it locked and unlocked a little more smoothly. That thing just rolls on the inside of the upper receiver (charging handle channel). That a crock. It only "rolls" against the upper when the bolt is fully extended - and when the bolt is fully extended, it's under no pressure. What a bunch of shiit...

Your receiver sets are made by Matrix Aerospace, and the external dimensions are identical to the Ruger SR-762 (Matrix made those, too). The Ruger has some weird things going on inside, something proprietary, and that's why I said "external dimensions..." Matrix made this receiver set with both DPMS barrel threading and Armalite AR-10 barrel threading. It looks like DB went with the DPMS-based barrel threading. Just so you know - the only thing "Armalite" or "AR-10" about the DB10s is the angled cut on the receivers - nothing else. Check this recent thread out:

There's a method to this madness - I like it. It's about to get serious, brother...

The gas keys are identical. But, please explain more about removing the gas key so you can (take out the cam pin?) remove your bolt for cleaning? I've never had to remove a gas key to take out a bolt, so I don't understand what you're talking about...

It's either 1/8" thick or 3/16" thick. Easy to measure with a tape measure. Just trying to save you some headaches, and find the right part for you. Pretty complicated, isn't it? The only thing Armalite about the receiver set you have is the cut on the upper/lower...