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1/25/2018 7:38:29 AM
Posted: 9/15/2003 5:07:19 AM EST
[Last Edit: 9/16/2003 7:15:16 AM EST by Green0]
I have had no problems removing many of these in the past but Bushmaster pins give me a lot of trouble. I had to do a lot of crazy stuff to get the last Bushmaster pins out.

Now my brother bought an M4 barrel and needs to remove the pins and can't get it done.

Does anybody have any help with this??? (I've been trying to punch them out left to right - I hope that's right.)

Should I heat the front sight post with a torch?
Link Posted: 9/15/2003 7:58:47 AM EST
I cannot remember which way the pins go in, you should be able to look at them and see which end of the pin is smaller and whack on that end. I would put some thin oil like Rem-Oil on the pins and let it soak in for awhile. Then take a matching punch and hammer and they will pop right out.
Link Posted: 9/15/2003 10:09:06 AM EST
I allready beat on them for about half an hour and they wouldn't come out. am I the only one who has a problem getting Bushy pins to come out? Every BM barrel I get has this problem and this one is the worst yet.
Link Posted: 9/15/2003 11:50:52 AM EST
Had the same problem and solved it. I tried so many things I'm not sure which one or a combination of all worked but here is what I did. Beat on it forever with hammer and punch. Soaked for couple days in penetrating oil. Heated with a Blow torch. Stuck it in the freezer over night. Found the biggest punch (that would still fit in the holes, it was about 6 in. long and pretty heavy, and got a heavier hammer like 20 oz.) Beat on it some more and they finally came out.
Link Posted: 9/15/2003 12:02:12 PM EST
It really makes you wonder how anyone can make money working on these things... $50 to install a FF RAS and then go through that and waist 3+ hours on it...
Link Posted: 9/15/2003 7:49:36 PM EST
Support the barrel & front sight post on the most solid/immovable object you can find. If you don't have the thing supported adequately, the energy from your hammer blows will just be absorbed by your support rather than being focused on the pins. Position your drift punch on the side that is the smallest diameter. If you have just succeeded in mushrooming the end of the pin by hitting it too many times you may have to drill it out. If so do it very carefully or leave that to a pro.
Link Posted: 9/15/2003 8:37:25 PM EST
Originally Posted By Russ4777: Support the barrel & front sight post on the most solid/immovable object you can find. If you don't have the thing supported adequately, the energy from your hammer blows will just be absorbed by your support rather than being focused on the pins. Position your drift punch on the side that is the smallest diameter. If you have just succeeded in mushrooming the end of the pin by hitting it too many times you may have to drill it out. If so do it very carefully or leave that to a pro.
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What he said. Also, use a HEAVY (1-1/2 or 2 pound) and strike the punch FIRMLY. One or two solid blows will get them out, you can pound all day with a lighter hammer/light taps and NEVER get them out. Also, KROIL penetrating oil and a little heat could be used, but shouldn't be necessary. I use a 1/4" diameter brass punch to break the pins loose, so I don't deform the ends, and it won't slip off and f*ck up the sight base.
Link Posted: 9/16/2003 4:45:32 AM EST
Easy rule of thumb on Bushmaster's (may apply to other brands, but I don't own any so I can't say for sure): the taper pins come out the same side as the ejected shells. I have had similar problems with the taper pins on my Bushy, only in reverse. I got them out OK, but I wasn't able to drive one of them all the way back in when I reassembled it. The pin is flush with the front sight base on the back side, and sticks out twice as far on the front side as it should. I don't think its going anywhere, but I may have swelled the head of the taper pin by beating on it too much. Russ4777 has it right. You need to support the barrel with a solid backstop and use a HEAVY hammer. I am going to order some new taper pins and start over on mine when I get the chance. This time I am going to lay the barrel on a concrete floor with just a think layer of material to protect the finish on the barrel. It helps to have a second person hold the barrel steady, since it usually wants to bounce and rotate when you strike the punch.
Link Posted: 9/16/2003 7:14:59 AM EST
I'll try tomorrow. Thanks for all the advice (I think the brass punch sounds like a good idea). Luckilly my brother is getting a RAS MRE so we can re-blue the few scratches and cover them up where they won't be seen.
Link Posted: 9/16/2003 9:39:44 AM EST
I had the same problem. I used a smaller diameter finishing nail that was blunted and whacked the crap out of it with a heavier hammer. don't be shy, hit it with everything you got...it'll come out. it took me about 20 minutes to drive it out. mushroomed the crap out of my punches the first time around.
Link Posted: 9/16/2003 6:37:37 PM EST
I found keeping the dang punches on the pins was harder than getting the pins out. I ended up laying the sight/gas block on a 1X4 board and screwing down some 1X2's around the sight to lock it in place. I then placed another 1X4 on top of the whole lower wooden brace and pounded it with a rubber mallet to make an impression of the pin locations. I then removed the top board, drilled two through holes (same size as punch diameter), one for each pin location, to guide and hold my punches as well as protect my barrel/forend from stray hammer blows. I then screwed the top board back into place and gave the punches some good whacks. Not elegant, but it did work.
Link Posted: 9/16/2003 6:50:56 PM EST
If I'm not mistaken, your are supposed to use new taper pins to reinstall.
Link Posted: 9/17/2003 4:37:46 AM EST
Willamette, The taper pins have a rounded surface on the ends. A standard pin punch is flat on the end. A taper pin punch has a concave surface that matches the rounded end of the taper pin. This keeps it from constantly slipping off when you strike it. Taper pin punches aren't always easy to find in a typical hardware store, but they work a lot better.
Link Posted: 9/17/2003 7:49:28 AM EST
Same problem with my Bushy. I opened my bench vise about 1/2 inch and positioned the pins in the gap. Then I put some crap wood under rear part of the barrel for support. That left my hands free for the punch and hammer. I used leather to protect the finish from the vise, but scratched up the other side from the many times the punch slipped off.
Link Posted: 9/17/2003 7:15:15 PM EST
I tried again and it didn't work. I was beating the crap out of it. I think im just going to grind the pins down flat and then try to punch them out with a pin punch. Also I heated the front post red hot before I tried to punch them out...it didnt help one bit.
Link Posted: 9/18/2003 8:36:57 PM EST
Brouhaha took a grinder to my Bushmaster front sight to get the pin that would not come out. Of course then I put a new PRI front sight on... Make sure the pins are larger on one side then the other and you drive out the small end to the large side. There have been Bushmasters where the pins were driven in from the wrong side. Use calipers if you cant eyeball it.
Link Posted: 9/19/2003 7:54:56 AM EST
I ground the pin flat and beat on it again and it did not come out. So I heated the barrel to near red hot and beat the crap out of it. It still didn't come out. Then I took advantage of the fact that it was hot and put oil on the taper pins. Maybe that will help. I think it's about time to consider sending it to someone to have the pins drilled out. (I don't know why BUSHY puts in taper pins anyway. simple round pins work fine.) They seem to think the thing will be used as a tool to Rivet I-beams with.) They could learn a lesson from model one sales or Colt here (model 1 uses roll pins and colt uses round pins with flat ends if I remember correctly. [b]Now I wonder what this is going to cost me. (one pin ground flat and beat the hell out of. the other demon I haven't even touched yet.)[/b]
Link Posted: 9/19/2003 8:10:18 AM EST
I give up I tried again and it is not going anywhere. I think I'm going to call Bushmaster about it.. They need to know what a pain in the ass those pins are. They act like a heat fit (like the barrel was heated and then the pins punched in.) The finish is screwed I'm going to have to moly coat.
Link Posted: 9/20/2003 8:01:33 AM EST
GreenO, Try this: Cut two pieces of 4x4x1/2" oak liberated from an oak pallet. Take a Dremel tool and cut a channel in them across the grain. If you don't have a Dremel, just use a regular cross cut saw and a round file to make a channel about 1/3" deep. You want to make a round channel that's deep enough to get a good grip on your barrel. Go to a sporting goods store and get a $1 bag of rosin that baseball guys and weightlifters use. Dust the channel and place in a bench vise. Insert barrel forward of your front sight into the channel and tighten it down with the narrow part of the pins facing up, so you can look down on them and also soak them with oil while you're at it. Tap them out. Here's a pic: [url]http://www.ofoto.com/PhotoView.jsp?collid=25558273403&photoid=180495460103&UV=190373748447_763675460103&refreshkey=1064076902966[/url] You can also scroll through that album and see two other pics of the blocks. I've used those blocks on around fourteen or so barrelling projects and they're still going strong. Cheap, too. It will work, just think through it and have patience. It isn't rocket science, but I know it can be frustrating, and I was, too, until I figured out this method. I just used those on a preban colt upper that I bought. I was installing freefloat handguards and had to remove the front sight post. You should get new tapered pins, too. Jim
Link Posted: 9/20/2003 8:47:45 AM EST
Thanks for the info.. Unfortunately my workbench is made out of 2x4's and plywood and my vise is not very solid for hammering on. I have been using the cement floor as a workbench. MSTN said that there are two very important things: 1 to have the concave taper pin punch and 2 to use a brass hammer (he says he uses a ten once brass hammer and it works great) the brass is supposed to have more dwell time and deliver a stronger blow with less weight. [b]I think that Bushmaster screwed this one up I don't have any Kroil oil, and I am going to call BM on monday and talk to their gunsmith to see what he reccomends. If he can do it for less than $50 I would rather pay him than further damage my barrel by beating the hell out of it. By the way I guess I was the first guy to ever complain that BM taper pins are mounted to firmly (they don't need to be anywhere near this strongly set to do their job.) I told them that my 5 previous barrels were a total pain in the ass too. This one is just far worse.[/b]
Link Posted: 9/20/2003 9:39:01 AM EST
I have used a large tree trunk for a pounding block. Check out someone who is cutting trees in your are and get a section of trunk about 2 to 3 feet long and about 2 to 2.5 feet in diameter. Set it on the ground or driveway slab and pound away. Using this method gives you a solid base and a soft surface to minimize damaging the item being beat on. The great thing about using this method is that it is often free and easily replaceable.
Link Posted: 9/20/2003 7:36:04 PM EST
You could always try this: [img]http://www.infopackets.com/graphics/jack+hammer+the+mouse.gif[/img]
Link Posted: 9/20/2003 7:58:29 PM EST
For those looking for concave punches, Brownell's carries concave punches for rounded pins - they are meant to work on Smith and Wesson pistol pins. Also, you may want to try using a brass tipped deadblow hammer. Me? Never removed any, I get someone else to do the dirty work (MSTN). You'd think there would be a support jig designed for this, or perhaps a jig that removes them like sight pushers, though from the sounds of it, it would not be strong enough...
Link Posted: 9/20/2003 9:36:58 PM EST
If it still isn't happening and BM wont help send it to me I have a press set up for these sums a bitches, stick in the ffloat and I will install it. Just send me enough to cover priority shipping it back. My good deed for the year [o:)] Robert www.rbprecision.com
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