rail damaged

2616 Views 28 Replies 10 Participants Last post by FloridaAKM, Jun 30, 2010

leeroy

Discussion Starter · May 20, 2010

Right rail is damaged towards the rear.Also jamming every third or fourth shot.I know this is vague and there are no pics but any advice?

1 - 20 of 29 Posts

Fritz

· #2 · May 20, 2010

leeroy said:
Right rail is damaged towards the rear.Also jamming every third or fourth shot.I know this is vague and there are no pics but any advice?

You need more info especially if you don't have pictures. Factory rifle? Home build? 100% receiver? if so what was the manufacturer? fold your own flat? manufacturer of the flat? weld your own rails in? what kind of damage? What are the jams? failures to feed? failures to extract? failures to eject?

My car is damaged and doesn't run. How do I fix it?

leeroy

Discussion Starter · #3 · May 20, 2010

Home built-screws underfolder W/ flat I bent and welded rails on-unsure of manufacturer.
Jams:ftf bullet jams on bottom of feed ramp/front trunnion
Damaged part of rail is slightly bent down 1/16" +- I'll work on pics
This gun shot fine for 300 rds or so.Not all at once over a few years.50 here 50 there.
Thanks ,Leeroy
Should I be in BIY AK-47 ?

00redZX-6R

· #4 · May 20, 2010

Does this happen with all of your magazines?

brianakell

· #5 · May 20, 2010

Id say pics first.

Or, empty the receiver, carefully bend the rail back, make sure the carrier slides smooth, then add carrier and bolt. Then get the trigger group back in there. Youll probably find something playing with that.

ACMcom

· #6 · May 20, 2010

leeroy said:
Home built-screws underfolder W/ flat I bent and welded rails on-unsure of manufacturer.
Jams:ftf bullet jams on bottom of feed ramp/front trunnion
Damaged part of rail is slightly bent down 1/16" +- I'll work on pics
This gun shot fine for 300 rds or so.Not all at once over a few years.50 here 50 there.

Perhaps the rail height is incorrect.
There really shouldn't be enough pressure on the rails to cause them to bend down.
As already posted, pull the fcg and bend the rail back.
Then put the carrier and bolt in and slide it back and forth, looking to see if the bolt binds on the rails at any point.
Remember that if the rail on the other side is too high it might cause the bolt to cock. That might cause the other rail to bend if the bolt lug put pressure on the rail.
It might also be the cause of, or contribute to your feed problem.

leeroy

Discussion Starter · #7 · May 21, 2010

took out fcg rail height differs from one side to the other
how many times can you rebuild these guns?
I'm thinking of going with a 100% receiver....

FloridaAKM

· #8 · May 21, 2010

If you don't destroy the parts removing them from the U-folded receiver, the 100% receiver will give you less problems after a correct build. You don't want to keep spending money on replacing receivers for a rebuild...........

leeroy

Discussion Starter · #9 · May 22, 2010

Suggestions for best made 100% receiver ?(underfolder)
Thanks

1biggun

· #10 · May 22, 2010

NDS if they make what you want. post pics of yours I dont uderstand why it needs to be replaced??

Coils

· #11 · May 23, 2010

I dont uderstand why it needs to be replaced??

The way it sounds, the receiver isn't bent right, the upper rails are at different hieght.

Also agree, the NoDak's are nice receivers. The NDS1P should be what you need, if your on a tight budget or just don't want to spend much you could make the NDS3 work but you'll have extra holes toward the back

leeroy

Discussion Starter · #12 · May 23, 2010

Sorry I was'nt more specific here. I am talking about the right lower rail (the bolt rail)not the rails for the bolt carrier.Is it possible to remove the damaged rail clean up and spot weld a new one on without taking receiver off? I'll try to get help with pics
Thanks

Coils

· #13 · May 24, 2010

OK, got it now.
The only way I can think of doing it would be to drill out the spot welds then use a mig (a wire feed welder might work too), plug weld it back in, then grind down the welds.

leeroy

Discussion Starter · #14 · May 24, 2010 (Edited)

The bolt is catching on the hammer(forward and rearward) which in turn seems to bind up the carrier- fine with the fcg removed,it is not getting caught up on the rails anywhere.
Any more thoughts?

leeroy

Discussion Starter · #15 · May 25, 2010

bear with a beginner here: If the left ejector has 'nt had enough material removed would this cause the bolt and carrier to jump to the right ?
7.62x39 ejector needs less width than 5.45x39,correct?

ACMcom

· #16 · May 25, 2010

Perhaps, but there would have to be a lot of excess material, since the bolt has some play in the carrier.
Does the edge of the ejector show signs of wear? How about the inside of the ejector cut in the bolt?
Any signs of wear on the top or bottom of the ejector where the cocked bolt might rub on it?

jreifsch80

· #17 · May 26, 2010

oh some of your issues sound familiar. sounds like a tapco flat (i build on them and have some of the same problems) yeah i found with mine that the hammer will cause the bolt carrier to bind mainly when it comes back forward and would infact even stop the bolt carrier from coming forward i carefully grinded with a dremel an angle in the top of the hammer and formed a ramp with it is cocked so the bolt carrier wouldnt hang up but not too far down as if you go too far down could take off too much matterial on the hammer that the safty spur on the back of the bolt carrier wont block the hammer from firing out of battery, do a search on here about the hammer mods and you'll find more info. also if the ejector isn't ground down enough it will push the bolt and carrier over to the right and cause binding as well. in fact if too long it will bind the bold and carrier so bad they will be stuck in the closed position causing a big headache and force you to cut out your lef rail to get the bolt and carrier out ( ask how i know about this problem, hahaha it sucks) anyway totten kopf has a good instruction in the library about fitting your ejector length as there are manye other good bits of info on here from others as well, as for what i did was i test fit the bolt ony on my lower rails by hand sliding the bolt forward and i filed the ejector down untill it would just barely stop moving the tail of the bolt over to the right side, then i tested with the bolt carrier by hand and it seemed to be just right went to the range and works perfect throwing cases about 10-15 feet straight to the side of me when shooting with no problems yet. i hope i wasn't too confusing.

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leeroy

Discussion Starter · #18 · May 28, 2010

Originally I had left the hammer/hammer pin in the receiver while checking things out. Took them out and now I see the rear right side rail weld has failed and the rail has play which is why I thought there was a height difference.
So I'm thinking the hammer mod will stop the bolt/bolt carrier from hammering the rail and grind a fraction off the ejector.(possibly replacing right rail.What do you all think?
Thanks,Lee

ACMcom

· #19 · May 28, 2010

I have a rifle built on a TAPCO flat. The hammer is an unmodified G2. The rails have never come loose. I've put 4K+ shots through the rifle.
The pressure from the hammer is on the carrier, not the bolt. Further, the pressure forces the carrier up, towards the bottom of the upper rails, not down toward the lower rails.

1biggun

· #20 · May 29, 2010

need pics and did you lube it?? its normal for a hammer to put pressure n the carrier. will the gun cycle at all???

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