I have a Baer upper I want to use for a project. Since it’s a Baer product, they of course have clung to their ridiculous “tight makes right” philosophy and I can barely get this upper onto a lower without a hammer, and taking it apart damn near requires a hydraulic press.
So, this begs the question, best way to loosen the fit? I’m obviously not a big tightness nut, but I also don’t want it to get so sloppy that it induces feeding issues or rattles around like a cheap Pinto going over rumble strips. I want the pins hand-operable but not much beyond that.
I understand that I probably need to open up the holes, but I’m looking for some feedback from someone that might have done it before. Specifically, tools/method, pivot hole vs. takedown (or both), etc.
Never had that issue. Usually the exact opposite.
Now for a few questions for you:
Is the upper tight to where you have no play at pin holes AND body(never got to play with a Baer).
Have you tried opening the holes and using makeshift pins(I know,I know you don’t want to, just had to once. Don’t ask).
Have you tried it on a known loose lower. Maybe it will work magic and solve both problems.
Rob, you have a metric shit ton more knowledge than I, just trying to give you what I can.
I’ve put this upper on every assembled lower I own (which is more than a few) and no joy on any. To be clear, the issue isn’t one of wobble/no wobble, it’s an issue of getting the pins to go in at all. I literally have to beat on them with a rubber mallet to get them in. The fact that it happens on every lower, and that I know Baer’s ridiculous way they build everything over-tight, not to mention their shit customer service reputation, leads me to believe this is intentional on their part and is something I should be able to rectify at home and will probably have to.
OK. Got ya.
Padded vice.
Number drill set.
Drill press or one hell of an eye and a hand drill.
Or round file.
ETA: just saw last post, damn that’s just odd. Good luck brother. Sounds like your gonna have to either hit the hole or the body and remove material with a dremel or send it to someone.
Remove material till desired fit is achieved . That’s the easiest I could tell you.
I have had some very tight upper/lower fit rifles and carbines.
I made them acceptable with the following methods:
1- Slow. Completely strip pins and lugs of any lubrication. Using nylon punch, repeatedly insert and remove pins until do-able by hand while shaking assembled weapon.
2- Medium. Completely strip pins and lugs of any lubrication. Rub pin hole in upper lugs with Flitz or a bore paste. Cycle pins as above.
3- Fast. Be careful, if you make you upper looser than a Phillipino lady-boy, it ain’t my fault. Be warned.
Take a new brass bore brush and chuck it into a variable speed hand-drill. Insert brush into takedown pin hole. Start slow, gradually increasing speed of the drill. Check fit frequently.
Use a old take down pin load it up with lapping compound and chuck it in a drill . Never tried it just an idea.
Yea basically what failer2stop posted along with the same precautions.
If you didn’t know, the take-down pin hole in a Colt upper receiver is not round. It is in fact elongated. This ensures fitment/interchangeability. I would guess that take-down pin hole in the Baer is has just been reamed straight.
I certainly agree with F2S that any cutting tools should be kept away from the project. You might also try using the shank of a 1/4 drill or a spare take-down pin to lap the pin hole with some aluminum oxide lapping compound…
My thinking is in parallel with the above posts.
I might try using a set of those EZ-Pull Pins for tools along with bore paste/lapping compound combined with elbow grease (cycling).
If elbow grease was not enough I would chuck up some bar stock of the correct diameter in a cordless with bore paste and hit it with some slow, careful RPM.
I would try lightly sanding the pins with some crocus cloth and leave the holes alone. Crocus cloth comes in 3 grits and is used for fine finishing of metal parts. If you have any extra takedown pins laying around check them for fit, I have had some that were .001" undersize.
I guess I stand corrected. But I’ve yet to have dramatic overkill"ladyboy" looseness(that really is funny F2S). But I see how it could easily happen in the wrong hands.
I’m actually pretty sure that even with power tools I wouldn’t screw this up.
This thing is INSANELY tight. I’ve seen tight before, but this is just bananas. I am not at all exaggerating when I say I have to beat on the pins to get them to seat, and I do mean beat.
The one thing I haven’t done yet is test-fit loose pins to the holes to see how that goes. I can tell you that unlike some tight uppers I’ve dealt with in the past it doesn’t matter which pin you drive in first, both are equally tight, which leads me to believe that both holes will need opening up.
I have dealt with this problem a couple of times. You don’t need power tools. I have used both a small, round, fine file and and a wooden dowel with 150 grt sand paper.
Open up both holes a little at a time, frequently rechecking fit. My best guess is you will barely remove the anodizing inside the holes before you get the fit you want.
IIRC there was a thread on TOS by a guy that had the same problem with a brand new rifle he bought from them.
He sent it back and they told him they fixed it and shipped it back to him. They ground/machined/filed the top of the lower and the guy was not happy with it.
Are the pins in the upper tight by themselves or are they tight for the whole upper/lower assembly?
I take it you are using one of their flattop uppers without a forward assist? Correct?
If that is the case, another option would be to buy a Colt 750 LMG upper, remove the receiver, and sell off the rest. I know this isn’t very likely but is another way to get what you want and their won’t be any fuck ups.
I need to test fit loose pins in the upper. I haven’t done that. I’ve tried mounting the upper on every lower I have (several Colts, several BCM, an LMT, a Sully, and an old Bushmaster) and in all cases the pins have to be pounded in with a rubber mallet to get them in.
Yes, it’s a Baer flattop non-FA. I’d love to have a 750 stripped upper but something tells me that would be cost-prohibitive.
