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I assembled my first AR lower yesterday!

This topic can be found at:
https://sigforum.com/eve/forums/a/tpc/f/630601935/m/8310065064

September 02, 2019, 10:01 AM
Jman78
I assembled my first AR lower yesterday!
Had a PSA AR kit sitting for about a week. On a whim yesterday i decided to try assemble the kit.

Working with the only tools on hand, a hammer, a screw driver, hex wrench set, and a helpful youtube video. No vise or anything, my hand and my stomach was the vise lol.

It took me about 1.5 hours. Most of time was used up in trying to get the front retaining pin and spring in. The pivot pin launched 3 times, luckily i found it. My thumb is sore from using it to hold the pin is as i slid the hex wrench through the holes to hold everything together, but while getting the pin in, it slipped a few times, making me repeat the whole process all over again.

The rest of the process went smoothly, just had to visit the local gun shop to borrow their caste nut wrench and to finish hammering in the pin on the trigger guard.

Not as bad i read with people loosing pin and springs and destroying the trigger guard ears.

I only have one small scratch from the hammer, but not bad considering i had no protection on the lower.

If you havn't tried it, go for it, it is easy, and just requires a lot of patience depending on the level of "right tools for the job".
September 02, 2019, 11:20 AM
CandyMan.45
this is probably the beginning of the end for you... 1 leads to 2 and that leads to 3 ! With enough practice you'll eventually get it done in under 10 minutes...
September 02, 2019, 11:40 AM
WARPIG602
quote:
Originally posted by CandyMan.45:
this is probably the beginning of the end for you... 1 leads to 2 and that leads to 3 ! With enough practice you'll eventually get it done in under 10 minutes...


Facts.

Im down to about 20 minutes or less if I use the PWS ratcheting castle nut system. Need to work on my bolt catch roll pin install time.


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September 02, 2019, 11:44 AM
WARPIG602
quote:
Originally posted by Jman78:

It took me about 1.5 hours. Most of time was used up in trying to get the front retaining pin and spring in. The pivot pin launched 3 times, luckily I found it. My thumb is sore from using it to hold the pin is as I slid the hex wrench through the holes to hold everything together, but while getting the pin in, it slipped a few times, making me repeat the whole process all over again.

T


Invest in a .10 razor, install inside of large ziplock bag to save time from searching for catapulted pins. I used the razor which is about twice as fast as the way you're doing it now. Then I bought the Wheeler tool which is about quick as it gets ad pretty much foolproof. Probably the best value when you factor in your time and cost of lost pins Smile


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September 02, 2019, 12:24 PM
LDD
quote:
Originally posted by Jman78:

It took me about 1.5 hours. Most of time was used up in trying to get the front retaining pin and spring in. The pivot pin launched 3 times, luckily i found it.


1/4" clevis pin.

1. Put the clevis pin in the pivot pin channel.
2. Align one of the holes in the clevis pin with the hole that accepts the spring and detent.
3. Drop the spring in first through the hole in the clevis pin, followed by the detent.
4. Depress the detent with an appropriately sized punch, till it is completely inside the hole.
5. Use the punch to rotate the clevis pin so that the clevis pin blocks the detent and keeps the detent in the pivot pin detent channel.
6. Use the the front pivot pin to push the clevis pin out of the way (come in from the correct side, and it helps to have the channel relief in the pin facing the detent, so when you slide the pivot pin in, there's no need to further rotate it).
7. Marvel at how easy that was and will never spend 1.5 hours doing an 8 second job again.

Youtube video showing how easy this is:
https://www.youtube.com/watch?v=M7DrFEDw3ow
September 02, 2019, 12:39 PM
RogueJSK
Congrats!

After you've done a few, you can get it down to 10ish minutes.

Putting a few strips of painters tape in a few areas can help prevent scratches, especially with the bolt catch.

The suggestions for using a clevis pin and large Ziploc when doing the front detent pin are spot on.
September 02, 2019, 09:38 PM
Texas Bob C.
Do you feel a twitch? That's your body telling you it wants to build another one.
September 03, 2019, 12:47 AM
bubbatime
Check your hammer spring. Half the newbs install this spring backwards, which gives you light primer strikes and the hammer pin keeps working itself lose.


______________________________________________________
Often times a very small man can cast a very large shadow
September 03, 2019, 11:55 AM
BucFan
quote:
Originally posted by Texas Bob C.:
Do you feel a twitch? That's your body telling you it wants to build another one.


All so true. I buy complete uppers, but do enjoy buying and installing the parts of my choice onto a stripped lower.



Sig P229R 9mm - Sig P365 NRA
Sig P320C 9mm - Sig P320 FS .40
September 03, 2019, 11:57 AM
Anubismp
One of the most important tools I have for assembly is a large flashlight so I can find my projectile parts on the floor. I'm only kind of joking.
September 03, 2019, 03:05 PM
1gkek
quote:
Originally posted by LDD:

1/4" clevis pin.



Clevis pin for the win. My first has turned into... 5.
September 03, 2019, 10:31 PM
AZSigs
quote:
Originally posted by LDD:
quote:
Originally posted by Jman78:



1/4" clevis pin.


Wish I had known about this years ago. I struggled forever with a front pivot pin on many a build.




Getting shot is no achievement. Hitting your enemy is. NRA Endowment Member . NRA instructor
September 03, 2019, 10:33 PM
TRshootem
Normal lower assembly goes pretty smoothly. I have most of the proper tools....but man, this last lower was a nightmare. Roll pins were hard and a bit oversize, the lower itself seemed to be a bit out of spec. I installed a BCM hand guard, most difficult sumbitch to fit over the barrel nut. After having done 50+ builds, I hope to never encounter one like this again. In the end, my parts stash saved the day Smile
September 05, 2019, 06:22 PM
wxdave
Black Rifle Disease is contracted swiftly and it is deadly. There is no cure!


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Floridian by birth, Seminole by the grace of God