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JeepHeep
03-05-19, 20:30
So i recently purchased the 5d tactical jig pro that included a lower from 80-lower. Everything milled out just fine, followed the instructions to the T! Took it out of the jig and i see daylight where my pistol grip goes! Pretty sure it's toast. What do you guys think?https://uploads.tapatalk-cdn.com/20190306/554ee53e754f8b38e4fe8608a91847ae.jpghttps://uploads.tapatalk-cdn.com/20190306/d0407b212f1df82e386380335dad9d9f.jpghttps://uploads.tapatalk-cdn.com/20190306/e81f28ab4d9eaae4319ea73bffeb1636.jpghttps://uploads.tapatalk-cdn.com/20190306/633900a6e501c59f02034b69213716a2.jpg

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militarymoron
03-05-19, 21:23
How thin is the bottom of the receiver where the trigger comes out? Either the instructions were wrong or you misinterpreted them, because that pocket looks much too deep. The only thing that bears against the bottom of the pocket is the trigger spring. If the bottom is 'wafer thin', then it might be toast.
JeepHeep
03-05-19, 21:52
It seems to taper. The edge is about 1/16 but the middle of the slot is about 1/32. This is my first lower so im not 100% on what exactly im looking for

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prepare
03-06-19, 05:26
Make sure the mil (bit) is locking. What router did you use?
GH41
03-06-19, 06:43
Looks like a 300 dollar paperweight to me.
mic2377
03-06-19, 09:41
So it looks like what happened is by milling this deeper, you are not far off from detaching where grip mounts. Who knows how strong it is. I would consider it ruined.

Also out of curiosity, did you say that this is your first lower ever? Perhaps it is probably a good idea to have another standard mil-spec lower around for comparison sake before you go milling one out?
prepare
03-06-19, 11:26
Did you use the router plate with the bearing in it?
JeepHeep
03-06-19, 12:03
I did use the cap with the bearing. And i had used the ridgid router from home depot i kept checking my depth on the jig and it all seemed correct. The only thing i can thing of is kaybe my bit came loose because i did have to tighten it at one point.

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prepare
03-06-19, 13:53
I did use the cap with the bearing. And i had used the ridgid router from home depot i kept checking my depth on the jig and it all seemed correct. The only thing i can thing of is kaybe my bit came loose because i did have to tighten it at one point.

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Yeah, it looks like there are a few chatter marks that could indicate a loose mill nut.
Sorry it didn’t turn out so well. Brownells has 80% lowers reasonably priced if you want to try again.
glockshooter
03-06-19, 18:57
Well it’s not ruined, but i would limit it to a range gun. The area you milled to deeply does add much if any strength to the grip screw area. There is nothing it a lower that is high pressure or abused by the operating system.
MegademiC
03-06-19, 20:30
Yeah, it looks like there are a few chatter marks that could indicate a loose mill nut.
Sorry it didn’t turn out so well. Brownells has 80% lowers reasonably priced if you want to try again.

I just looked- why are andersone 80% $10 more than complete lowers? - rhetorical question


Well it’s not ruined, but i would limit it to a range gun. The area you milled to deeply does add much if any strength to the grip screw area. There is nothing it a lower that is high pressure or abused by the operating system.

Could always look into one of those shotgun stocks on it. I assume they wouldput less stress there. Or just start over and cut your loss.
Diamondback
03-06-19, 22:16
I'm not an expert, but if I'd done that I'd probably blue-stripe it and restrict as a Range/Training/Competition gun. IF my understanding is correct based on my old engineering classes, all the real load is in the upper and the buffer tower/tube anyway.
JeepHeep
03-06-19, 22:28
Thank you all for the info it has really helped. I may just put it together until another 80 comes in and then probably swap a few pieces over. Lesson learned.. check to make sure my endmill isn't walking away on me

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Renegade
03-06-19, 22:36
nah, JB weld to fill it in, or get someone to tig weld it.
Diamondback
03-06-19, 22:39
Yeah, recheck and if need be tighten up the chucks on your tooling is VERY important, too. My first plastic EPL, when I was drilling pilot holes for the FCG pocket, I put the tip of my 3/32" drill bit through the sidewall in a non-Load Bearing area... that lower's been sprayed orange and set aside for a .22LR upper.

But hey, I successfully completed an AR lower using only a cordless drill, so there's that! :D
rpoL98
03-06-19, 23:55
nah, JB weld to fill it in, or get someone to tig weld it.

or JB Weld a piece of aluminum plate into the bottom to build up the thickness somewhat. Should be okay, remember, they make AR lower receivers out of polymer nowadays also.
SteveS
03-07-19, 07:53
Put the lower together and see if it works. In todays pc world you effed up I said it sorry if it hurts your feeling. That being said if you never try things you will never eff up. Try doing another lower and go even slower.