Should I grind on this thing or what?

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[ARCHIVED THREAD] - Should I grind on this thing or what?

Posted: 9/20/2004 6:38:37 PM EDT

One of my buds has an Oly lower and a God-only-knows upper. The pivot pin inserts fine, however the takedown pin is almost impossible to get inserted. To do so, we have to apply awkward pressure to the upper and lower. It appears to be too tight at the rear of the upper and where the buffer tube inserts into the lower. Should we attempt to grind the upper just enough for a better fit.......or are we heading for disaster since there is another EASIER and LOGICAL way? Thanks in advance for your reply...

Posted: 9/20/2004 7:28:44 PM EDT

[#1]

Do you have any pics of the problem? If its just tight, but still fits and functions, I would just leave it alone. If not, its hard to tell without pictures.

Also, where are you in GA? Metro Atlanta has a bunch of GA ARFCOMers that can help you. If you can wait until the next shoot, I'm sure someone will be more than happy to help.

Posted: 9/20/2004 10:11:35 PM EDT

[#2]

Can you insert the takedown pin THEN the pivot pin? Does the buffer tube protrude from the lower?

Posted: 9/21/2004 4:38:04 AM EDT

[#3]

Hey Ghost.....I'm in Brunswick, GA I don't really get a chance to goto any shoots :-((

Hey Tweak.....We haven't tried to opposite pin insertion thing. However, even though it works "technically" I would sure not wanna be shooting and have an issue that would require breakdown and not be able to complete the fix. The buffer tube doesn't protrude from the lower, it is a great fit there so I'm at a loss.

He has a digital camera that I'm gonna borrow and then hoard so I can post pics here oneday, but for now I don't.

Posted: 9/21/2004 3:15:27 PM EDT

[#4]

Strip the pivot and takedown pins from the lower and set the upper on it. Do the pin holes line up? Is there too much material at the top of the magwell above the pivot pin?

Posted: 9/23/2004 4:20:48 AM EDT

[#5]

i would gring the pin before the upper. which part is cheaper?
i had a lower with offset takedown holes... i did just that, dremel the hell out of the rear takedown pin until it fit right. you could always just tap it in with a rubber mallet too.

Posted: 9/23/2004 4:42:21 PM EDT

[#6]

Bushy's uppers are notorious for this. At the top of the rear lug (takedown pin) you will probably notice on each side, a very small raised radius hiding up there in the corner of the lug. If this IS your case, just dremel a VERY little off of each side until the upper fits snugly into the lower. I have had to do this several times when mixing busy's uppers with others manufacturer's lowers. The good news is that you will have a perfect fit when done. You can use cold blue or Aluminum black to finish the work and you will never be able to tell.

Posted: 9/29/2004 8:23:19 AM EDT

[#7]

Is this a new lower? if so, and you judge it to be out of spec, send it to OLY and get 'em to fix it. They have a pretty liberal policy on fixing their mistakes. If it is an older lower...send it to OLY and get 'em to fix it. Lifetime Guarentee is a wonderful thing.

My old SGW stopsign lower (OLD Oly) is ever so slightly out of spec w/ regards to the takedown pin. I chose to releave the rear pin hole on my new upper. Your choice.

HTH
ka

Posted: 9/30/2004 7:48:28 PM EDT

[#8]

Some people actually buy this Acu-wedge thing to accomplish what you have...

Posted: 10/1/2004 6:48:40 AM EDT

[#9]

Accu-Wedge.......hmm wow, I thought that was to TIGHTEN a receiver, not LOOSEN it!

Posted: 10/1/2004 8:31:38 AM EDT

[#10]

sigh... that was a sarcasm...

But I feel your pain.. I have an old Oly lower that has the same problem. It seems to work ok with an A1 upper but really, really tight with all my A3s.

I took a little metal off the inside of the upper rear lug hole. (Elongated the bottom) And keep a plastic handled flat head when I go to the range.

No free play between upper and lower... Even better than my Acc-Wedged 24"

Posted: 10/1/2004 8:36:28 AM EDT

[#11]

Some folks like it tight...................

Posted: 10/1/2004 8:46:20 AM EDT

[#12]

I've seen the same problem with several Oly lowers trying to mate with in spec uppers.

Posted: 10/1/2004 10:35:17 AM EDT

[#13]

Sorry man, bad day here......waiting more than 2 months on a Bushy 24" barrel. I appreciate all your input on this and I suppose the only synopsis of the problem is that Olympic Arms doesn't really make that great of a product! I've owned one before selling it and my bud now owns this pain in the ass.........Never again for me, and Bushmaster is treading thin on my patience with this barrel order too!

[ARCHIVED THREAD] - Should I grind on this thing or what?

AR-15 » Troubleshooting

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