Front Takedown pin hole

[kottke_35]

So I've had my 450 Bushmaster since September 2011. I bought a complete 16" rifle package from Gander Mountain. Since the day I got it, my front take down pin hole in the upper itself has been very tight. So tight that I have to use a wooden dowel and a hammer to move the pin. I took the upper off and put it on my Rock River lower, same issue, put my Rock River Upper on my Bushmaster lower, no problem.

So I believe the problem would be the front hole of the 450 Upper where the take down pin goes. What can I do to loosen this so I can switch out uppers without having to carry tools?

Thanks guys!
B.

[Texas Sheepdawg]

It will break in with time and rounds fired. The tighter it is the better accuracy. If you can use a wooden pin to remove it
I would just leave it be. Also. When taking down your AR, it's best to remove the rear pin first. That makes it easier to remove the front pin, if you have to. Most guys I know would rather have it tighter that loose or sloppy. Is it really so tight, it won't even allow the upper to tilt? You may just need a new takedown pin.

[Hoot]

It will break in with time and rounds fired. The tighter it is the better accuracy. If you can use a wooden pin to remove it
I would just leave it be. Also. When taking down your AR, it's best to remove the rear pin first. That makes it easier to remove the front pin, if you have to. Most guys I know would rather have it tighter that loose or sloppy. Is it really so tight, it won't even allow the upper to tilt? You may just need a new takedown pin.

+1

Mine started out tight and after 1k+ rounds it's so loose as to wobble in all four quadrants. Looseness will come whether you want it or not. Aluminum can only take that kind of stress for so long before it yields. It's one of the few beefs I have with the AR platform when used with powerful calibers. I sort of wish the design had been around pins that are slightly softer than the receiver material. That way, the pins would deteriorate and all you'd be out is the price of a couple a pins every now and then. I guess while I'm wishing, it probably should be for neither holes nor pins that batter out of spec over time...

Hoot

[Ghost Dog]

For totally different reasons I put these in my lowers, pulling the pins is now a piece of cake. Might help?



YHM EZ Pull Takedown Pin Set

[kottke_35]

Thanks guys. I figured it would loosen over time. The problem seems to be the upper receiver, not the take down pin. I switched the upper to my Rock River lower thinking that the take down pin was the culprit but no joy. Had the same issue, then moved my 223 upper to the bushy lower and it worked just fine!

So I'll deal with it being tight until she gets broke in I guess. I like the tension but that's a little too tight.

Thanks,
B.

[commander faschisto]

OK, thats it...I will now take up the challenge of ending this problem in the AR platform, one that some enterprising young lad should have solved 40 years ago. I'll keep you posted.

[BayouBob]

If it really is too tight it may just be the anodizing is a causing the hole in the upper to be too small. If you have acces to a set of numbered drill bits find the one that will just barely fit and twist it around a little with just your fingers. Don't use it in a drill; you will instantly waller the hole out. Like the others have said though, give it a few hundred rounds and it will probably loosen up.

[kottke_35]

If it really is too tight it may just be the anodizing is a causing the hole in the upper to be too small. If you have acces to a set of numbered drill bits find the one that will just barely fit and twist it around a little with just your fingers. Don't use it in a drill; you will instantly waller the hole out. Like the others have said though, give it a few hundred rounds and it will probably loosen up.

You were correct sir. Anodizing was the culprit.

Thanks,
Bryan