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Posted: 5/11/2003 5:38:06 AM EST
Someone please post a picture os a Thermold Mag showing where you Filed/Altered it so it would work fine in a Bushy Rifle?
They are hard to Latch as it is hitting the bolt and someone said to file the Top Lips of the Mag down a little? Please show me where you altered your thermold's to fit?
Link Posted: 5/11/2003 7:16:05 AM EST
The more popular method is to insert the thermold with the bolt locked open. Then drop the bolt and work it back and forth 20-30 times. The bolt itself will take off just enough of the extra material from the feed lips to allow the mag to fit exactly. No file needed.
Link Posted: 5/11/2003 7:47:19 AM EST
[Last Edit: 5/11/2003 7:47:36 AM EST by fell-off-the-truck]
Thanks for the reply. If i knew where to File I would rather use a File on them? Anyone have a picture of a Thermold that could show me the Area that would need filing? Thanks..
Link Posted: 5/11/2003 10:09:36 AM EST
It is just the top of the lips as sometimes the molding process leaves a little extra material on the lip, causing the bolt to hang up. XM777's advice is probably better than using a file, then you don't have to worry about taking off too much material. Another way is to use a knive and hold it perpendicular to the lips and drag it across the lips a few times to scrape off the flash. The knive doesn't have to be sharp, in fact it probably works best with a dull knife or even a butter knife. If you are set on using a file, then lay it flat across the top of the lips and take a couple strokes, put it in the lower and try it. Repeat as necessary.
Link Posted: 5/13/2003 3:55:51 AM EST
[Last Edit: 5/13/2003 3:57:23 AM EST by shamayim]
It may not be the feed lips causing the problem. My own experience is that neither Bushie nor Rock River chamfer the bottom of the mag well as deeply as Colt, and the mags hit the bottom of the reciever, impeding full seating. Rock River seems be worse in this respect, but my Bushie also had this problem to an extent. To find out where the problem is, insert the mag w/the bolt open. If it goes right in, the feed lips are the problem. If it hangs up even w/the bolt open, then the rib on the sides is hitting the bottom of the mag well. If that's the problem, just take a small fine cut file, and work down that side rib a bit.
Link Posted: 5/15/2003 3:04:04 PM EST
Link Posted: 5/15/2003 3:22:12 PM EST
Thanks, Troy! I have found that there are multiple problems, and they are different from the 30 round Thermold and the 30/45. This is not just a problem on your Bushy, but also on some other brands of AR type rifles. In the above pictures, the top shows a modification I made to the cutout where the bolt stop engages the mag's follower. Originally there was a narrow U-shaped cut there. I think this area was intended to be trimmed out and was not for whatever reason. The narrow U cut and general bulk would interfere with the bolt catch, and make it difficult to insert the mag. So, compare the Thermold's upper rear to that of a USGI 30 rnd mag, and you can see the difference, and where to grind away the excess plastic. I used a 1/4" dia cylindrical mill with my Dremel. This is the first place to start. The second shows the rib trimmed down.
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