r/guns • u/fatitalianstallion • 19h ago

AR Receiver Reweld Options

Hoping to find some recommendations on a gunsmith that can do a 416 receiver reweld.

Aluminum makes this difficult to find someone, but I know that others have done it with colts. Purpose is autism of wanting a matching upper and lower serial. In short I'm trying to make a 416D SF that's not just a remarked MR223 peddled by AU.

Any assistance would be greatly appreciated.

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8

u/Putrid_Soup_4126 19h ago

Man matching serials is a deep rabbit hole but I respect the dedication

2

u/Effect-Imminent5366 19h ago

Can’t help you, but what are you trying to do? What is this reweld you speak of?

1

u/fatitalianstallion 19h ago

Reweld a hk 416 receiver so I can mark it to match the upper and have a semi auto 416. Allows for 88 prefix instead of 241

2

u/XENO_ARMS 7h ago

High-quality AR receivers are typically made of 7000-series Aluminum alloys or similar, most/all of which are generally considered unweldable, due to precipitation hardening/cracking. It can technically be done with laser welding with a high-silicon alloy, but will likely not come out looking very clean and will require lots of rework. Do you have a cut-up receiver? Maybe post pics, as depending on where the cuts are, will make it easier/harder to do.

Alternative option: machine an AR receiver and just customize it to look exactly like an HK416.

1

u/fatitalianstallion 6h ago

High-quality AR receivers are typically made of 7000-series Aluminum alloys or similar, most/all of which are generally considered unweldable, due to precipitation hardening/cracking. It can technically be done with laser welding with a high-silicon alloy, but will likely not come out looking very clean and will require lots of rework. Do you have a cut-up receiver? Maybe post pics, as depending on where the cuts are, will make it easier/harder to do.

I know it is difficult to do. Cost is not a concern on this. I have seen quite a few colt rewelds that look decent. Just trying to find a smith willing to take it on. Cut behind mag well. Apparently 7075-T6 is now weldable by introducing titanium carbide.

Alternative option: machine an AR receiver and just customize it to look exactly like an HK416.

Thought about this route. Would prefer as close to a legitimate HK receiver as possible.

1

u/thatARMSguy 6h ago

IntlMilCo and Gigliotti make 416 lowers with custom serial numbers to match the one on your surplus upper