Precision Point Lower takedown pins wont fit any uppers

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I recently purchased a Preban Precision Point stripped lower, I stalled the parts kit, buffer tube, etc... and everything went well.

When I tried to mate the upper onto the lower, the takedown pins didn't line up. It seems like if I push the rear takedown pin in, the front wont line up.

When I push the front takedown pin in first, the rear of the upper seems like it hits the buffer tube assy first so it wont sit flush on the lower.

Does anyone else have one of these lowers with the same issue?

The upper is an aero precision: AR15 Stripped Upper Receiver with "A" Aero Logo - Anodized Black

Here are some pictures for reference.IMG_3598.jpg IMG_3599.jpg IMG_3600.jpg IMG_3601.jpg IMG_3602.jpg IMG_3603.jpg
 
I had this problem with a JP .308 EBR. The upper was promptly replaced by JP and it not only fits, but I have confirmed upper/lower interchangeability with my other JP .308.

It was not caught at the factory since I had an upper shipped for an existing completed lower assembly.

Watch out for fixes that involve enlarging the lower hole - though if it is lower and not the upper, you may be stuck with that fix because we are behind enemy lines. You may be able to get a good idea which is off by trying the upper/lower with the upper/lower from another weapon in your armory.
 
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Not to be a dick, but it’s pretty easy to check the pins before assembly. I had the same problem you had and learned this lesson the hard way. I’d screw with modding the pins if all else fails for the reason Rob states.

I broke an ear off a lower screwing around assembling. I bought the tools but my pre 94s go to Tim at Gartman.
 
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Not to be a dick, but it’s pretty easy to check the pins before assembly. I had the same problem you had and learned this lesson the hard way
This is a perfect example of life giving the exam first and the lesson later.
 
Hindsight is always 20/20, if there ever is a next time I'll check to see if the pins line up first but to be honest I never thought the takedown pin holes wouldn't line up.

I know the aero upper will fit on a ruger lower fine and the PPF lower will not fit on the ruger upper so I'm leaning towards it being an issue with the lower.
 
I know the aero upper will fit on a ruger lower fine and the PPF lower will not fit on the ruger upper so I'm leaning towards it being an issue with the lower.
My condolences sir.
 
So the upper fits on another lower and two different upper don’t fit on the PPF lower?

Well, I think you have yours answer. I’m also assuming bayou mean pre healey “ban”
 
I pulled the takedown pins out of the lower and it looks like the holes are only off by 1 thousandth. I might file or sand the pin to fit. Its better than filing the lower or upper. Thanks for the suggestions.
 
This is the first time I have heard of this problem. These lowers have a built in tensioning screw with a rubber tip that acts as an accuwedge to eliminate any sort of slop between the upper and lower.

It's possible the previous owner cranked it up in order to accommodate a poorly made upper.


Most aftermarket Pistol grips have an access hole for this screw. I would suggest unscrewing the screw a few turns and try it again.

tensionscrew.jpg
 
This is the first time I have heard of this problem. These lowers have a built in tensioning screw with a rubber tip that acts as an accuwedge to eliminate any sort of slop between the upper and lower.

It's possible the previous owner cranked it up in order to accommodate a poorly made upper.


Most aftermarket Pistol grips have an access hole for this screw. I would suggest unscrewing the screw a few turns and try it again.

tensionscrew.jpg

That was the first thing I tried, I then started removing all of the parts out of the upper and lower to make sure there was nothing interfering.

Does anyone know what the distance is supposed to be between the takedown pins? I have some calipers, I’ll check both and see what’s the culprit.
 
I had a similar situation last week.
But in my case it was the holes on the upper.

I have a marked 22LR lower that has worked with multiple different 223 uppers. I bought a used CZ 22LR upper just to have in the safe just incase there is a question as to why I have a newer lower with a 223 on me..
Cut to the chase.
The 22 upper would mate with the 22 lower the same way in your pics. The rear pin wouldn't go all the way thru. So in my case I know the lower and pins are good to go and not the issue.
So I just slightly enlarged the rear hole on the upper. Knowing I didn't care what happened to it. The lower is more important.
In your case if you can either tweak the pins.. It's the easiest solution.

But you might be able to send your lower back to the manufacturer if it's out of spec.
If you own it Legally.. You can get it back from them as a repair.
I told Tim at Gartman about an issue I had with a Spikes lower I fixed on my own. He said I could have sent it back to Spikes without worrying about it.
 
I wish I could send it back but it’s from The previous owner of Precision Point and they haven’t been made in years.

I might check with aero precision and see if it’s the upper.
 
The offedness is front to back, so it is not going to be the tension screw. Even being off by .01" or so is enough to prevent the holes from lining up properly.
I broke an ear off a lower screwing around assembling. I bought the tools but my pre 94s go to Tim at Gartman.
This is why I send my lowers to JP to have parts installed. Well, this and the roll pin for the ejection port door.
 
One time I had a similar problem which ended up being the front pivot holes being cut at an angle. Removing some metal from the front pivot pin is probably the safest and cheapest fix.

Dave
 
I wish I could send it back but it’s from The previous owner of Precision Point and they haven’t been made in years.

I might check with aero precision and see if it’s the upper.

You wouldn't have much luck, He is an ass hole.

Have you tried a different upper receiver thats not Ruger or Aero
 
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Do you have gage pins to check the hole alignment ? Start at .02 undersized and work your way up to find the largest pin that will go through. If it is in fact .001, maybe use a reamer, file, or a turned down takedown pin. Without welding and remachining the hole, those are the cheapest options.
 
I believe I too have one of those PP lowers, and pins did not line up correctly with a new upper I was using. I'll check when I get home tonite, don't want to say for sure till I check it out again. My memory sucks, but I vaguely remember an issue...
 
I believe I too have one of those PP lowers, and pins did not line up correctly with a new upper I was using. I'll check when I get home tonite, don't want to say for sure till I check it out again. My memory sucks, but I vaguely remember an issue...

I appreciate it, I’m curious to see if yours is the same.
 
I posted on another thread about this very problem with Noreen billet lowers. With them I am pretty sure it is variability in the thickness of the anodization that results in the slight out of spec of the lower. I just stick the lower on the mill and extend the front hole a couple 1000s, cold blue inside the hole and call it good.
 
If it was the thickness of the anodizing, you would not see the stud from the upper on one edge of the hole - the hole would symmetrically smaller and you would not see any part of the upper connection stud. It is because the hole is improperly placed. The fact that extending the hold a couple of thous shows how precisely this needs to be placed. It's not like the staking ping on a GI gas block where the holes are drilled as a unit - it is precision manufacturing of two separate parts.
 
Just to double check, I grabbed the Ruger upper, put the front screw in first and even though it was super tight and I needed to tap it in with a rubber mallet I was able to mate the upper and PPF lower. The Aero upper has no way of getting the rear takedown pin in.
 
I just got back from Northeast Arms, they put the upper on and pin in no problem.

I think I was babying it and being too gentle. It’s a super snug fit, but it fit.

I appreciate the suggestions but I think I was being a pussy when putting it together.
 
I just got back from Northeast Arms, they put the upper on and pin in no problem.

I think I was babying it and being too gentle. It’s a super snug fit, but it fit.

I appreciate the suggestions but I think I was being a pussy when putting it together.

I wouldn't say that. All three parts, lower, upper and takedown pins can be in-spec and yet the pins have to be forced in due to the way the three components are toleranced.

The hole center spec. for the upper and lower is 6.375" +/-.002", the hole diameter spec. is .251" +/-.001" and the mil-spec takedown pin diameter is a nominal .250".

If the upper and lower hole center spacing is off in opposite directions there can be a 0.004" misalignment even through both parts are in-spec. and that is not helped by the very tight nominal fit of the takedown pins.

The parts will "wear-in" now they're assembled but that's not really what's happening, it's more that the front holes of the lower and the rear lug of the upper become slightly distorted.

A good mechanical design would machine the holes in the upper and lower together like line-boring a crankcase or leave the hole in the upper rear lug slightly oval to accommodate any misalignment.

This is all a good argument for buying the upper and lower at the same time from the same manufacturer but here behind the pussyhat curtain we can no longer do that. Oh well.
 
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