Hello!
I’m working on my first build and am having a horrible time getting the pivot pin to fit. I got the spring and the detent in and the pivot pin in past them, but it doesn’t want to budge any further.
I’m using a PSA lower parts kit with an Anderson lower.
I used a hammer to get it part way through before deciding I should ask for advice. The videos I’ve watched it just slides right in. What am I doing wrong?
Did you try putting the pivot pin through the two empty slots without spring and detent in the channel? If it slides through empty, without the spring and detent in the channel, it may be an issue with the spring being too long, stiff, or the detent being out of spec. Put some lube on the pivot pin itself, and try sliding into the slots to eliminate the spring/detent being out of spec issue first.
Agree. Its always best to do a Test Fit before adding Spring Pressure to things like this.
I use a Tool that allows me to depress the Spring and Detent then Pull back and Replace the Tool with the Take Down Pin. This tool also verifies everything is in Spec if used correctly.
I’d follow the 1st responders advice and start over. Double Check your parts for correct spring or a deformed detent that wont recess.
A Hammer should Never be part of this process.
This is the Front Pivot/ Take Down Pin Tool
I use…the Tool allows you to Pre Check the Receivers Ear Holes for correct diameter…so if this fits the receiver and the Pin doesn’t? You know its Not the Receiver out of Spec.
The same applies to the Spring and Detent Recess being true. … Or the Detent being improperly formed, thus preventing it from compressing into the Spring Recess.
This product is made by Wheeler and usually goes for about $10.
Yes there are cheaper and manual options…but this helps insure the quality of the pieces going into your assembly process. I have over time installed them without any mechanical assistance…but I still verified things with a Test Fitment first… nothing under spring load.
A must for people building more than One AR in my opinion
I always put some gun grease in the hole, and some in the slot of the pin before assembly - as a “Break in” lube, then work the pin back and forth after install.
That said - Anderson Lowers Strikes Again…… 
Oil it and keep doing it. It will eventually wear in.
Have the same tool, its absolutley amazing…I always lube up the parts and put some grease in the channel. I had a detent that was quite sharp and a bit tough to get moving. Other detents I had werent as much so, and easier to move past that locking point.
Looking again at exactly how deep the Pin is into the Pivot Ear… you should have heard a small metallic click as the Detent Popped into the channel of the back of the Take Down Pin.
Did you hear that Click?
With the Pin in as far as it is…if it goes no further its binding on a deformed detent or somehow you got the wrong spring installed and its creating resistance.
I think you need to try to drive it with a Non-Metallic Mallet …Non-Marring Hammer…make sure the Receiever is well supported and padded when you drive the Pin from Right to Left…use some Oil. No WD-40.
Done with patience , it either works or you might need another Detent.
For the purpose of knowing what lies ahead. Take the Rear Take Down Pin and stick it in tge Left Side Pivot Ear to see if its within Spec?
The Two Pins are the same diameter.
Do the Pin through receiver fitment check on the Rear Pin later in the assembly process too.
I have very little experience with this and did my first build just last Sat. I found the pins to be tight so I put a tiny drop of oil to help them through the first time. They were hard to work in but now they slide just fine after using them quite a few times. I have a PSA lower so not sure if that has anything to do with it because I’ve heard bad stuff about Anderson lowers lack of QC and tolerances.
Funny thing Anderson is an OEM manufacturer for many AR companies.
The exact same thing happened to me on my last week and with an Anderson lower and PSA lower build kit. It eventually worked itself out but was very stiff in the beginning. Finally, the detent just fell into place. I thought it was weird never had that happen before, then you post about it so just corroborate what the OP said. I was building a JAKL lower when that happened.
Thank you for all the input!!
I slide the rear takedown pin in through the other ear and it fit fine. I’m thinking it might be a spring/detent issue and/or I got overzealous and tried brute strength rather than oiling it up and taking my time.
I’m going to take another stab at it using all the input.
I have Two Anderson Lowers in my collection.
The first I bought on Purpose because it was disgustingly economically priced and I was throwing together a "20 barreled Rifle designed to be as lightweight as I could make it
from Spares , Gimme’s and Bargain Bin pieces I’d found over time.
The Upper was a Stripped PSA M4 Flat Top mated to a Brownell’s Pencil Barrel where the Prototype Front Sight Blocks had been Mis-Drilled so they were practically giving them away. All of this was mated to a skinny Key Mod Free Floating Rail… out of Vogue and priced to move.
The above PSA , Anderson turned into a very economical and fun rifle to shoot , without giving a damn if it gets bumped or bruised along the way.
The Anderson based A2 Lower aquired Friday in a combo purchase is to say the least a Dumpster Fire in Fitment Terms. Completely out of Spec as measured against numerous other makes on hand.
We can say my ownership so far gives me a 50/50 ratio on Consumer satisfaction regarding Anderson… if that same ratio were to occur with my PSA’s , Colts, SAA’s , Aero Precision, FN’s or even Delton’s…I would be doing business with them again.
I wont be buying anymore Anderson Receivers unless its bundled into a deal I can’t pass on.
Keep us Posted DarkCoy
Will do! It may be a bit cause I’ve been working like crazy.
It’s not the frame, it’s the kit. Mic your pins.
I ALWAYS use a reamer or a drill bit by hand to make sure all the holes are the right size and don’t have any burrs in them. It saves time and broken parts. Especially with the ears that are fragile
So I finally had time to work on it.
I managed to get the pin lose and removed the detent and spring. They looked identical to the other ones in the kit.
I attempted to push the pin through the ears without a detent or spring in place - it doesn’t fit. The pin is too big. I tried putting it through both the left and right ears, plus through the rear pivot holes. It’s too big for all of them.
Meanwhile the rear pin fits just fine through all of the holes.
Any suggestions on my next course of action?
Coy ,
Two Options....get handy with a small file and reshape the Pin carefully , if in fact it's the deformed piece?
If Your Detent Spring is Recessing correctly ? , that’s a good indication the boss hole in the Receiver itself is in Spec…but not 100% certainty.
Do you see any deformaties compared to the detent used to retain the rear Take Down Pin?
The Only other Pin left is the Detent Pin for the Selector Switch…and it dwarfs the other two.
Next option…check with a local gunshop and see if they have a loose pin laying around to souvenir ya?
Last… buy a Complete Oops Kit that includes every little dicky-doo item that might get lost along the way.
Keep the faith…this Will sort out with patience.