AR Sponsor
Posted: 4/22/2003 5:56:40 PM EDT
| I have just finished my first build on a Eagle Arms lower and am having trouble with my buffer reatainer coming out ang getting stuck. Is it safe to use the rifle without the retainer and spring? |
|
What kind of buffer tube are you using (full length or carbine)? The edge of the buffer tube should be up against the post of the buffer retainer, but not so tight that the retainer and spring can't move up and down within the hole in the lower receiver. As far as I know, it's safe to fire the rifle without the buffer retainer and spring, as the bolt carrier will keep it in place. However, I only play a gunsmith on TV - any other thoughts on this? |
|
You need to screw the receiver extension in one more turn. If the tube will not allow this, you will need to shorten the bottom of the tube at the retaining pin to allow the tube to be spun the added turn, and maybe relieve the top of the tube to allow the carrier to slip past the top. As stated, the receiver extension needs to be on top of the outer lip of the retain pin, just short of the center post. Remember to press the retaining pin down as you screw the tube over the top. |
|
Are you guys saying the buffer tube should be touching the buffer retainer center post or not touching the center post? Dano, could you elaborate more on the following. If the tube will not allow this, you will need to shorten the bottom of the tube at the retaining pin to allow the tube to be spun the added turn, and maybe relieve the top of the tube to allow the carrier to slip past the top. I'm not sure exactly how/what you mean by "shorten the bottom of the tube...." Thanks all! |
|
On a telescoping stock tube (receiver extension), the tube should be just a thick black hair short of touching the center post. This means the tube is sitting on the outer step of the retaining pin and holding it in place/down. Some times the receiver or stock tube threads are cut out of spec (incorrectly index placement) which causes the tube to be either back too far, or if threaded one more turn, the end of the tube overlaps the center post, when the butt stock is indexed correctly. In this case, the open end of the tube will need to be slightly shorten to allow it to be threaded one more turn into the receiver to retain the pin, but not enough to overlap the center post. Most of the time when you shorten the tube end, the very top of the open end sticks a little past the top receiver threads into the receiver. This lip/open threads sticking into the receiver will bind/block the carrier as the upper/carrier is lowered down on the lower. At the top of the tube, you just need to shorten the tube top back so it is flush with the top/back of the receiver. Think of the end of the tube being a slightly angled cut, and not a true 90* cut. The bottom is longer to retain the pin, and the top is shorter to not stick out past the inside of the receiver. On a fixed stock, the thread index is not important, the only distance that counts is the thread end to collar shoulder, since the butt stock does not index with the receiver extension, but a tab that sticks into the back of the receiver. If your still lost, IM me with an e-mail address and I will draw something up for you with specs. |
|
Here's a photo of my PWA lower with an A1 receiver extension/buffer tube: [img]http://home.attbi.com/~gnanagas/AR15_buffer_01.jpg[/img] I should clarify my previous statement - the buffer tube should be screwed in until it holds the buffer retainer in place, so the retainer doesn't go shooting off with the spring. As Dano said, you also have to be careful that you don't screw the tube in so far that the top edge of the tube sticks out and keeps you from closing the upper onto the lower receiver. If you're stuck in that situation where the only way to keep the retainer in place is to screw the buffer tube in too far, then you have to file off the top part which is keeping the upper from closing. I hope I haven't confused everyone [:)] |
| No need to reply, I answered my own question. Yes the threads do overlap the retainer by about a 32nd of an inch which is enough to keep it in place. I've been having this retaining pin problem since changing stocks and never knowing that the threads hold the retaing pin in place. THANK YOU ALL!!!!!!!!! |
|
Great post and information. I assembled my AR15 back in November and if I recall correctly I had to make one more turn in order to hold the buffer retaining pin in place. However, in doing so, the buffer tube was touching the center post on the buffer retainer pin. So, if I understand what you guys are saying I need to modify the buffer tube. I have no problem closing the upper to the lower receiver. BTW, this is a CAR buttstock, non-collapsible. Fight4yourrights, Thanks for the pic! My son has my AR15 (in another city) so I do not have it in front of me to compare and understand where the cut is located. Dano, As always, your posts are mucho appreciated and I learn something every time I read one of your posts. I realize how much more I need to learn or to put it another way, how much I do not know about how the AR15 operates. I am visiting my son this weekend so this will give me a chance to see if what I recall is correct ie, the buffer tube is in fact touching the center post on the buffer retaining pin. The gun had a few FTF when new but the last 5-700 rounds ran with no problems. Thanks again for everyones input! Chris |
AR Sponsor