This is what I’m thinking and want to make sure it is mechanically feasible and at the same time staying within confines of NJ law. Let me know what y’all think.

I bought an AR from the state I’m living in now. Moving up to NJ shortly. If I bought this NJ compliant upper https://www.stagarms.com/stag-15-minimalist-upper/

and attached to my current AR lower which is this https://www.stagarms.com/stag-15-3gun-elite/

would there be any issues with mixing and matching different models of lowers and uppers of the same manufacturer. I don’t think so but what do you guys think.

if it’s okay, I’d just have to find a vendor to pin the stock since then I would have a pinned/welded barrel, fixed stock, pistol grip, detachable mag, no grenade launcher, and no bayonet lug. This would make it a NJ compliant AR, am I on the right track with that statement?

best answer: Don't move to N.J.    That aside your on the right track. flashhider/threaded barrel is a no no, as is the stock. Yes pin and weld, but why not go plain barrel and an A2 stock and save a bunch of cash for ammo?  Mixing uppers and lowers is not an issue, just the evil features

If you are having compliance work done anyways, you might as well just have your existing rifle be made compliant by pinning the stock and muzzle device. It would be much cheaper than buying a whole new upper and then getting your stock pinned.

Otherwise, to answer your question, there is no issue in mixing and matching upper to lower, as long as they are both mil-spec. you "should" be fine. From a compliance standpoint, yes, it is legal to mix-n-match uppers/lowers.

No problems mixing and matching lowers. That's the nice thing about AR's. You may have a slight gap between upper and lower of different manufacturers but most of the time you won't.

You're the guy who posted the other thread about moving to NJ right? You could always keep your existing AR and modify it to be compliant with nj laws instead of buying an additional upper. I mean if you want to buy another upper go for it of course. Either way, you'll have to modify them.

A couple other things. You can order uppers and ship them to youraelf as they are not a firearm and just a part. So don't think you need to rush to buy it before moving here. 

If it's a 16" barre, it just needs to be pinned or welded. If it's under 16" like a 14.5" barrel and a 1.5" brake to meet 16" barrel length, then it needs to be pinned and welded.

Thanks guys. I really appreciate this. I don’t know why, but I just don’t want to mess with my current upper on my stag. It’s some mental block haha, I just don’t want to get it pinned. I think I’m just going to go the route of buying the cheaper model upper from stag and then have someone in NJ pin the stock....unlesss anyone has any recommendations on a cheap quality fixed stock (cheap quality....I don’t know if that makes much sense!) I could just switch out. I know it’s not the cheapest route I’m taking but I’ll still be going back and forth from my home state and NJ often so I figured I could just lug my lower with me and use my original upper when I come home to shoot.

RecessedFilter: thank you for the information on barrel length. Mine is 18” so I think I’m set there.

I’m also still debating on buying my shotgun before I come up. From what everyone has said there aren’t any real restrictions on pump actionas ( no round capacity, pistol grip ok, bayonet Mount ok, adjustable stock ok)

Any evil features for a shotgun aren’t NJ friendly? Or anything else I should be aware of before I purchase?

Evil features don't apply to pump action shot guns. ONLY Semi-Full-Auto. (Or, well, Semi-Auto if you're not an idiot).

Lambo2936: haha! Thanks. I’ve never even heard of “evil features” until I learned I was moving to nj. 

1 hour ago, RickyRacoon said:

Lambo2936: haha! Thanks. I’ve never even heard of “evil features” until I learned I was moving to nj. 

Apart from the evil features list for semiautomatics, the state of NJ has its own list of evil features.  They include the executive, legislative, and judicial branches, plus a host of unelected power-hungry bureaucrats.   Sadly, this list of evil features isn’t capped at 2.

14 hours ago, RickyRacoon said:

Lambo2936: haha! Thanks. I’ve never even heard of “evil features” until I learned I was moving to nj. 

For the record, there has not been one drive by bayoneting in NJ since 1989.

Dont forget "constructive intent", if you bring the non compliant parts and have a compliant rifle, you are still breaking the law.

That’s my next question. If I do go the route of pinning barrel/stock, do I have to send it to Nj to have the work done beforehand?

We do compliance work - if you need help, call me!

Easiest way to "pin" your stock

https://www.strikeindustries.com/shop/strike-industries-ar-stock-stop.html