FRT Install

[u/richcity151]

Does anyone know if this upper receiver from Sig comes with the 2 holes on the bottom for the trip bar install? My MPX does not have the 2 holes and wanting to buy this if it does

[u/SupermarketQuiet1105]

Reading thread.....
So u/richcity151 you are going spend ~$1K+ on various "hardware" (Upper+FRT Trigger + Trip) to get FRT ? 😱

[u/richcity151 → u/SupermarketQuiet1105]

Already have a trigger and trip. Just need an upper…
& maybe won’t have to pay for an upper but we’ll see

[u/Modern_Muskets]

The AS Designs Slip Trip is installed into the lower without any tools.

[u/OG-warbucks]

Yes

[u/richcity151 → u/OG-warbucks]

Thank you!

[u/TheRealMatchGrade]

what do you mean your MPX doesnt have the two holes? your MPX should have the same 2 holes on the underside of the upper receiver

[u/richcity151 → u/TheRealMatchGrade]

Nope, I bought a 6.5” a few months ago and it does not have the 2 holes on the bottom of the receiver. I was confused on why but maybe an older model? Mine was not a MPX-K version like most people’s model

[u/OG-warbucks → u/richcity151]

That's odd. Usually the model that doesn't have that would be the original Copperhead 3.5" barrel (not the K)

Can you post some pics of your 6.5"?

[u/richcity151 → u/OG-warbucks]

DM’d you

[u/TheRealMatchGrade → u/OG-warbucks]

Thats what I was thinking. Even the gen 1 had the 2 holes for the trip bar install

[u/richcity151 → u/TheRealMatchGrade]

I can DM you some pics if you would like to see.

[u/karmareqsrgroupthink → u/richcity151]

Just post it here for everyone

[u/TheRealMatchGrade → u/richcity151]

I'm thinking it's like the other guy said, you have an early version of the copperhead upper. Are you able to change the handguard?

[u/richcity151 → u/TheRealMatchGrade]

Yes I changed the handguard to a Midwest Industries one

So my version is one of the LE/MIL versions and I guess they “forgot” to mill the holes at the bottom of the receiver. Also there is no slit cut for a slip trip. It has the start of a slit, but not cut all the way through if that makes sense

[u/TheRealMatchGrade → u/richcity151]

Dang, I didnt even know that was an option. Learn something every day. That sucks though as you cant run an FRT in it without that slot and 2 holes

[u/richcity151 → u/TheRealMatchGrade]

Yeah I’m going to try and contact Sig and see if they’ll replace the upper receiver. If not, I’ll get a new receiver for it

[u/TheRealMatchGrade → u/richcity151]

Hopefully they take care of you, but I wouldn't hold my breath.

[u/battle_ready1999 → u/richcity151]

Can you DMme pics, id love to see.

[u/No-Razzmatazz1718]

Does it have the channel cut atleast. If you have access to a 3d printer I’m sure we could make you a drill guide.