Difference’s between takedown and pivot pins on pre-ban AR’s

[JD221]

Hello all,
First time poster here. I am in the market for buying a preBan AR and have noticed that there’s all different types of takedown and pivot pins some seem more desirable than others and I’ve read that some you can’t swap out could anyone give guidance please as to which ones are good which ones to stay away from etc.?
Any info and I will be appreciated thank you

 

[MGnoob]

The front pin on some prebans is a different size.. For example on my colt it’s larger than your modern AR pin. You either need to buy an upper with the larger pinhole.. Or they sell adapter pins that Cam. These pins arnt a perfect solution.. They come loose and sometimes break… Typically only under full auto use but it still happens.

Also the fire control group trigger pins can be different sizes but that’s not related to your question the more desirable lower receivers use the common small pin and sometimes allows for more trigger options.

Once again not that it’s applicable to you but when you buy an M-16 trigger they Mostly only come in the small pin variety.

To directly answer your question you can also send your receive out and they put a sleeve inside of the front pivot pin hole and pin it in there.

The other thing to considers is some preban receivers have what they call a sear block in there that prevents the use of a sear. Really not applicable with you but their less valuable/desirable. They can be removed. But there’s more to Then you need to know.

The only way all this information is relevant to you is help you determine the actual value of whichever receiver you pick. Under most circumstances if it’s your first one and it’s just Semi get yourself the cheapest one you can.

 

[556USER]

You can use these stripped uppers. I have and they are of good quality RobertRTG Upper

 

[mac1911]

There are solutions to these problems
Its a small worry once you get the preban

 

[JD221]

The front pin on some prebans is a different size.. For example on my colt it’s larger than your modern AR pin. You either need to buy an upper with the larger pinhole.. Or they sell adapter pins that Cam. These pins arnt a perfect solution.. They come loose and sometimes break… Typically only under full auto use but it still happens.

Also the fire control group trigger pins can be different sizes but that’s not related to your question the more desirable lower receivers use the common small pin and sometimes allows for more trigger options.

Once again not that it’s applicable to you but when you buy an M-16 trigger they Mostly only come in the small pin variety.

To directly answer your question you can also send your receive out and they put a sleeve inside of the front pivot pin hole and pin it in there.

The other thing to considers is some preban receivers have what they call a sear block in there that prevents the use of a sear. Really not applicable with you but their less valuable/desirable. They can be removed. But there’s more to Then you need to know.

The only way all this information is relevant to you is help you determine the actual value of whichever receiver you pick. Under most circumstances if it’s your first one and it’s just Semi get yourself the cheapest one you can.

Thank you very much!

 

[mac1911]

Thank you very much!

Here is one of the “fixes” this is for large pin lower to small pin upper.
Only issue is now your upper is “fixed” to your lower and need screw driver to split the upper from the lower. Also the cam pin can shift and bind the pivot.

Colt AR15/M16 Receiver Offset Adaptor Pin

adapts large pin colt lower receivers to fit standard small pin upper receivers. adaptor pin has a reduced diameter, offset center section. colt, ar15, m16, pre-ban, lower, receiver, offset, adaptor, pin, 206-lrpcap, 552340a, 552340b, offset pivot pin, semi auto, adaptor screw, colt adapter...

www.eabco.net

This one is to adapt large hole upper to small hole lower , these can also be tricky and rotate and bind the front pin

Colt Receiver Adapter Offset Bushing

COLT OFFSET BUSHING OFF SET ADAPTOR ADAPTER

www.jsesurplus.com

I think both designs can damage the lower if you flip it open with any binding.

Good thing if you have a large pin lower you can buy the large pin upper receiver
And build what you like. Its going to cost you

Big Hole Upper Receiver Assembly

The Daniel Defense Big Hole Flat Top Upper is designed and built with a .315 front pin hole to fit the early Colt lowers with .315 front holes. This eliminates the need to use an offset pin, which requires 2 screwdrivers during assembly / disassembly of these rifles. This upper comes with our...

danieldefense.com

Or just find a complete pre ban rifle you are happy with.

Oh I I think these are what replaces the fixed large take down pin on the colts?
DS Arms - KNS Precision Large Diameter Push Button Pivot Pin - Colt Style .315"

 

[MGnoob]

Here is one of the “fixes” this is for large pin lower to small pin upper.
Only issue is now your upper is “fixed” to your lower and need screw driver to split the upper from the lower. Also the cam pin can shift and bind the pivot.

Colt AR15/M16 Receiver Offset Adaptor Pin

adapts large pin colt lower receivers to fit standard small pin upper receivers. adaptor pin has a reduced diameter, offset center section. colt, ar15, m16, pre-ban, lower, receiver, offset, adaptor, pin, 206-lrpcap, 552340a, 552340b, offset pivot pin, semi auto, adaptor screw, colt adapter...

www.eabco.net

This one is to adapt large hole upper to small hole lower , these can also be tricky and rotate and bind the front pin

Colt Receiver Adapter Offset Bushing

COLT OFFSET BUSHING OFF SET ADAPTOR ADAPTER

www.jsesurplus.com

I think both designs can damage the lower if you flip it open with any binding.

Good thing if you have a large pin lower you can buy the large pin upper receiver
And build what you like. Its going to cost you

Big Hole Upper Receiver Assembly

The Daniel Defense Big Hole Flat Top Upper is designed and built with a .315 front pin hole to fit the early Colt lowers with .315 front holes. This eliminates the need to use an offset pin, which requires 2 screwdrivers during assembly / disassembly of these rifles. This upper comes with our...

danieldefense.com

Or just find a complete pre ban rifle you are happy with.

Oh I I think these are what replaces the fixed large take down pin on the colts?
DS Arms - KNS Precision Large Diameter Push Button Pivot Pin - Colt Style .315"

Definitely go with the adapter pin over the bushing.. The bushing moves all over the place. The pin just breaks every now and then And usually it’s just a defective part.. Buy a few of them you’ll eventually put one in there that won’t break and also let you adjust the gap between your upper and lower receiver.. Those bushing suck they just wander all over the place causing mystery problems. But it’s not a mystery it the bushing.

And don’t get too worried about your “collectible” pre-ban you’re gonna end up gouging out that hole with a screwdriver f***ing around with that adapter. It’s not that bad. It’s just peals off a little bit of your anodizing..

 

[MGnoob]

Here is one of the “fixes” this is for large pin lower to small pin upper.
Only issue is now your upper is “fixed” to your lower and need screw driver to split the upper from the lower. Also the cam pin can shift and bind the pivot.

Colt AR15/M16 Receiver Offset Adaptor Pin

adapts large pin colt lower receivers to fit standard small pin upper receivers. adaptor pin has a reduced diameter, offset center section. colt, ar15, m16, pre-ban, lower, receiver, offset, adaptor, pin, 206-lrpcap, 552340a, 552340b, offset pivot pin, semi auto, adaptor screw, colt adapter...

www.eabco.net

This one is to adapt large hole upper to small hole lower , these can also be tricky and rotate and bind the front pin

Colt Receiver Adapter Offset Bushing

COLT OFFSET BUSHING OFF SET ADAPTOR ADAPTER

www.jsesurplus.com

I think both designs can damage the lower if you flip it open with any binding.

Good thing if you have a large pin lower you can buy the large pin upper receiver
And build what you like. Its going to cost you

Big Hole Upper Receiver Assembly

The Daniel Defense Big Hole Flat Top Upper is designed and built with a .315 front pin hole to fit the early Colt lowers with .315 front holes. This eliminates the need to use an offset pin, which requires 2 screwdrivers during assembly / disassembly of these rifles. This upper comes with our...

danieldefense.com

Or just find a complete pre ban rifle you are happy with.

Oh I I think these are what replaces the fixed large take down pin on the colts?
DS Arms - KNS Precision Large Diameter Push Button Pivot Pin - Colt Style .315"

Those work OK.. But that doesn’t fix the problem with the colt lower large pin… You’d have to have a large pin upper receiver lug for that to work.. That ball detent pin is just for convenience. And basically useless. They have a better one that has a D ring attached to it that makes it super easy to rip out but you’re only gonna need that if your swapping uppers out all the time like I do. And I still don’t even use those they fail

Buying an entire preban rifle is pretty stupid if you plan on shooting it.

I have a particular lower which I Use for all of my fully automatic stuff, beltfeds or whatever but it’s gonna be of no use for you.

In all likelihood any pre-being lower you by will be just fine.

Edit I’m only referring to Your last image. Those detent pins

 

[MGnoob]

You don’t want a large pin upper. Buy the adapter pin.. It’s done and over with you’ll figure it out in 15 minutes

 

[MGnoob]

With the front adapter pin and the link below no matter how f***ed up your lower is with a little common sense everything will be fine. This plastic douche nozzle goes in the back of the gun. It’s just to keep a tight fit so once you get it all locked and it stays there. My bet is for the amount you’re going to shoot your rifle you’ll never have a problem.

Z-M WEAPONS AR-15/M16 ACCU-WEDGE | Brownells

Helps promote better accuracy by making the upper and lower receiver fit tighter. Open upper receiver; drop this long-wearing, rubber wedge into the ...

www.brownells.com

 

[MGnoob]

BROWNELLS AR-15/M16 ACCU-WEDGE | Brownells

One of the fastest, easiest, cheapest accuracy-improvements you’ll ever find for your AR! Tough, high-density synthetic rubber wedge drops into the space behind the takedown pin in the lower receiver to provide tension between the receiver halves ...

www.brownells.com

 

[Dench]

I used to own one of the large pin colt Preban lowers. For some reason the upper was not with it when I bought it. So, it had an offset pin. Which 100% no doubt about it blows. I believe the "correct" factory version is something like a screw.

Anyway, I bought a new upper thar was made for colt large pins. It costed me out the ass, I think the stripped upper was around $400. But it solved all the bullshit problems created by the offset pin. This large pin was essentially a giant version of a normal take down pin. Perfect!

I believe this upper is no longer made, sadly.

 

[MGnoob]

I just don’t think buying a large in upper is a good idea… Unless you’re just gonna buy one up or leave it on the rifle forever and I guess it’s OK. Some of the large been up or if they were selling for a while head tendency to fracture the lug on the upper receiver..

I definitely have a different thought process than your typical owner though so I’m not saying dench is wrong…

A lot of people used to drill out the front law that a lot of small pin uppers so they would work on their large pin lowers… They tend to fail. Summer better than others. But what were discussing here is a hack job..
If you want to customize your upper beyond factory. You’re going to wind up having to do one of several things. Depending on what you’re gonna do having the lower large front pin modified by a professional is definitely the best that but it has money to a lower. When you could buy something else. I’ll send you a link hold on

 

[MGnoob]

M60joes domain doesn’t exist anymore.. He might be dead that tends to happen… But if you Google him there’s plenty information about it this thread doesn’t have the pictures but it explains the gist of it I think. I’m sure other people do the modification but it was never cheap..
I’ve had him ramp 9 mm bolts for my AR 15 and I’m pretty sure he did the repairs on this your own. Not so much repairs but somebody had a drill and tap a hole in it so it is attached rear lug.. It’s actually pretty stupid modification in my opinion

 

[PappyM3]

Good thing if you have a large pin lower you can buy the large pin upper receiver
And build what you like. Its going to cost you

Big Hole Upper Receiver Assembly

The Daniel Defense Big Hole Flat Top Upper is designed and built with a .315 front pin hole to fit the early Colt lowers with .315 front holes. This eliminates the need to use an offset pin, which requires 2 screwdrivers during assembly / disassembly of these rifles. This upper comes with our...

danieldefense.com

Interesting. I didn’t realize those were still around.

 

[mac1911]

Definitely go with the adapter pin over the bushing.. The bushing moves all over the place. The pin just breaks every now and then And usually it’s just a defective part.. Buy a few of them you’ll eventually put one in there that won’t break and also let you adjust the gap between your upper and lower receiver.. Those bushing suck they just wander all over the place causing mystery problems. But it’s not a mystery it the bushing.

And don’t get too worried about your “collectible” pre-ban you’re gonna end up gouging out that hole with a screwdriver f***ing around with that adapter. It’s not that bad. It’s just peals off a little bit of your anodizing..

Collectable pre ban—- you mean grand dads old rifle.

 

[daveyburt]

I had an issue with the adapter pin. I needed to snug the pin while the rear pin was in the rifle (IE: assembled). If not, the bolt wouldn't unlock after firing a shot, and needed to be disassembled to free it up. I find them to be too 'tweaky'. I also didn't like that the adapter pin applies lateral pressure to that front hole - where the normal pin just sits in there happily.

-just my experience.

 

[MGnoob]

I don’t even consider prebans collectible Unless it’s unfired… And unless you live in a worst state in Massachusetts you’re better off buying a machine gun..

Collectable pre ban—- you mean grand dads old rifle.

 

[cathouse01]

Here is an old post of mine discussing the differences in an AR15’s pins:

AR 15 Complete Uppers in Mass

Go green sparky! Welcome to the forum

www.northeastshooters.com

If you know a really good gunsmith/welder they can weld over the large front pivot pin hole in the lower and then re-drill it at the proper offset as a small pin. You still won’t have a mil-spec lower, since all the large front pin lowers also came with large fire control pins, but it is easier to find large pin trigger replacements than it is to find large hole uppers.

 

[MGnoob]

If you really wanted to you could get that sleeve and align it right, then stake the bitch in there.. These probably have value now… It all depends on whether you’re a shooter or a collector. Either way it’s all a bunch of garbage, buy the cheapest one and figure it out.. Then you’ll know what to do when you get a good one.

It really just depends on how much you actually shoot.

Make sure you apply some frog lube

 

[paul73]

Here is an old post of mine discussing the differences in an AR15’s pins:

AR 15 Complete Uppers in Mass

Go green sparky! Welcome to the forum

www.northeastshooters.com

If you know a really good gunsmith/welder they can weld over the large front pivot pin hole in the lower and then re-drill it at the proper offset as a small pin. You still won’t have a mil-spec lower, since all the large front pin lowers also came with large fire control pins, but it is easier to find large pin trigger replacements than it is to find large hole uppers.

it is still beyond me how people still believe getting a pre-ban lower will give them some ephemerial benefits if a global confiscation of ARs would about to commence.
a stripped M4E1 lower now is readily available everywhere, can be transferred in and owned just fine. even cheapo $40 andersens are back. but, no, those prized cow old beaten up $1600 pre-bans are still the topic...

 

[MGnoob]

it is still beyond me how people still believe getting a pre-ban lower will give them some ephemerial benefits if a global confiscation of ARs would about to commence.
a stripped M4E1 lower now is readily available everywhere, can be transferred in and owned just fine. even cheapo $40 andersens are back. but, no, those prized cow old beaten up $1600 pre-bans are still the topic...

Global consfiscation? By that logic I shouldn’t buy any of these machine guns I own because they’re only a little widget that cost f***en Fortune. Buying a pre-ban it’s just a way to stay legal.

Any investment has a chance of going to shit. That applies to anything.

That $40 anderson lower Massachusetts might wind up with a $40,000 Court Bill… Even if you win you’re still out the money