Take Down Pin/Spring-Detent Hole 4-40x1/8" set screw......? - Page 1

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[ARCHIVED THREAD] - Take Down Pin/Spring-Detent Hole 4-40x1/8" set screw......?

Posted: 3/31/2015 4:46:40 PM EDT

My Aero Precision Gen2 lowers I just ordered come with the take down pin/spring-detent hole threaded for a 4-40x1/8" set screw, can someone tell me the best place to order some online? Also does it really matter IF I use the 316 stainless 4-40x1/8" set screws on a aluminium lower? Thanks in advance.

*EDIT*

Found these: https://www.fastenal.com/web/products/details/1125024?searchMode=productSearch&filterByVendingMachine=

https://www.fastenal.com/web/products/details/0177650?searchMode=productSearch&filterByVendingMachine=

https://www.fastenal.com/web/products/details/73207?searchMode=productSearch&filterByVendingMachine=

These would work just fine, correct?

Posted: 3/31/2015 4:53:43 PM EDT

[#1]

Just go to your local hardware store, or go on amazon and order them. I bought a 100 piece bag for like $5.00. Any hardware store or auto parts place should have them. Stainless or black doesn't matter. You end up trimming the screw or trimming the spring so it will not lock the pin in place, but will hold it tight. I like the system so much, I bought a 4/40 tap and do this to all my lowers. That way less of a PITA when you switch stocks.

Posted: 3/31/2015 4:57:15 PM EDT

[#2]

Quote History

Quoted:

Just go to your local hardware store, or go on amazon and order them. I bought a 100 piece bag for like $5.00. Any hardware store or auto parts place should have them. Stainless or black doesn't matter. You end up trimming the screw or trimming the spring so it will not lock the pin in place, but will hold it tight. I like the system so much, I bought a 4/40 tap and do this to all my lowers. That way less of a PITA when you switch stocks.

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Nice ,thanks.

Posted: 3/31/2015 5:21:06 PM EDT

[#3]

make sure it's not in there. if it's screwed in a little deep it can be hard to see. if not I have some extras. IM me your address and I will send you one.

Posted: 3/31/2015 5:25:50 PM EDT

[#4]

Quote History

Quoted:

make sure it's not in there. if it's screwed in a little deep it can be hard to see. if not I have some extras. IM me your address and I will send you one.

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The lowers haven’t arrived at my FFL yet, still waiting(next 4-5days). Thanks for the offer, come to find out I have a Fastenals not that far from me. I've probably driven by it many times & never paid attention to it LOL.

Posted: 3/31/2015 5:46:26 PM EDT

[#5]

I have worked on enough machinery with these setscrews rotted/seized up to cause major problems - I would not risk F'ing up your receiver to keep a one dollar part in place - Buy a couple of spare detents and springs - should have spares for the next build anyway -

Posted: 3/31/2015 5:54:33 PM EDT

[#6]

That is the correct size - regular steel or S/S.

ACE H/W usually has them, unless you went to my ACE store today – the box was empty.

Use anti-seize on the threads to prevent galling inasmuch as the set screw is steel and the Upper Receiver is aluminum. NO need for lock-tight in that the end plate will stop the set screw from backing-out and the spring will keep the set screw from moving forward.

The reason I do this is that for what every reason (hands the size of a picnic ham ??) I tend to bend the spring while I am installing the end-plate/buffer tube.

And OBTW I did have to remove a buffer tube in the field in that a casing got stuck between the gas tube and the top of the Upper Receiver.

Posted: 3/31/2015 6:10:37 PM EDT

[#7]

Quote History

Quoted:

That is the correct size - regular steel or S/S.

ACE H/W usually has them, unless you went to my ACE store today – the box was empty.

Use anti-seize on the threads to prevent galling inasmuch as the set screw is steel and the Upper Receiver is aluminum. NO need for lock-tight in that the end plate will stop the set screw from backing-out and the spring will keep the set screw from moving forward.

The reason I do this is that for what every reason (hands the size of a picnic ham ??) I tend to bend the spring while I am installing the end-plate/buffer tube.

And OBTW I did have to remove a buffer tube in the field in that a casing got stuck between the gas tube and the top of the Upper Receiver.

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Thanks for the headsup on anti-seize.

Posted: 3/31/2015 6:12:08 PM EDT

[#8]

Quote History

Quoted:

I have worked on enough machinery with these setscrews rotted/seized up to cause major problems - I would not risk F'ing up your receiver to keep a one dollar part in place - Buy a couple of spare detents and springs - should have spares for the next build anyway -

View Quote

I have not heard or read of anyone having any issues with these set screws rotting/seizing up in peoples lowers, maybe someone else has?

Posted: 3/31/2015 8:50:08 PM EDT

[#9]

I've done this mod on several lowers, and have an Aero lower with the mod. (The setscrew doesn't come with it, by the way.) Never had a single hint of a problem. And I've never seen any comments here about such problems either.

Posted: 3/31/2015 9:02:49 PM EDT

[#10]

In theory (and practice in many applications) galvanic corrosion can be a major problem when using steel and aluminum together. I only know enough about metallurgy to know I don't know enough, but I've done said mod on many of my and others ARs and so far not one issue. I us a little aeroshell as a piece of mind, at least the first time.

Posted: 3/31/2015 9:15:16 PM EDT

[#11]

The last couple I did I used a brass screw since the local hardware store didn't have any set screws. I just cut it off and cut a slot in it.

Posted: 3/31/2015 9:22:48 PM EDT

[#12]

Would this be the same set screw thats in Mega Arms lowers to "tighten" up the slop "IF" there is any?

https://www.fastenal.com/web/products/details/0154097?searchMode=productSearch&filterByVendingMachine=

Posted: 3/31/2015 10:40:39 PM EDT

[#13]

As stated above, a full service hardware store should have that set screw.
Don't forget to pick up an Allen wrench.....size .050" I believe.

I use my barrel nut grease for stuff like this and also will put a small dab in the detent track to help the two parts break in.
The anti-seize that I use on engines is too messy to get near my rifles.
If your safety selector seems too tight you may have the shorten the spring x the length of the set screw.