Splice connections for lengthening solar panel wires?

Dumb newbie question but to extend the wires can I just cut the connectors off of the plug end of the solar panel leads and splice another similar gauge wire using something like a simple butt connector?

Asked another way is there magic sauce in the wiring and connectors or is it just simple copper wire inside carrying the current from the little magic box under the panel?

Dumb newbie question but to extend the wires can I just cut the connectors off of the plug end of the solar panel leads and splice another similar gauge wire using something like a simple butt connector?

Asked another way is there magic sauce in the wiring and connectors or is it just simple copper wire inside carrying the current from the little magic box under the panel?

MC4 connectors are waterproof and UV resistant.
Whatever joinery you swap in will likely have to have those characteristics.
Cutting the connectors off the panels will probably decrease their resale value and overall utility to boot.

I go the other way and always hardwire my PV with quality automotive style butt joiners and UV resistant heatshrink.

MC4 connectors are built for speed of installation, they aren’t as good as a well crimped connection.

Disagree 100%. They are crimped as well as any other connection with the proper tool.

Sure, but then they rely on a male/female barrel connection which may be subjected to fretting corrosion. (i have seen this, along with water ingress as causes of failure).

Then consider anti-corrosion compound and/or heatshrink with glue inside.

"quality automotive style butt joiners"

Is that an oxymoron?

What voltage strings are you using?
I don't think I'd enjoy using a crimping tool on wires approaching 600 VDC.
This isn't the kind of terminal/crimper linemen use to tap off hot overhead AC power lines.

It does look to me like MC4 was made to be cheap and based on a Molex sheetmetal pins, compared to MC3 which appears to be higher quality.

https://www.amazon.com/MC4-Solar-Connector-Pins-set/dp/B013OAAX2W

Amazon.com: MC3 Solar Connector Pins 10 set. : Patio, Lawn & Garden

Amazon.com: MC3 Solar Connector Pins 10 set. : Patio, Lawn & Garden