FAL question.

**308bolt** · December 13, 2011, 13:26

Matching Austrian lower, bolt and carrier.
New DSA receiver and new DSA barrel.

The rifle refuses to cycle using matched carrier.
If I throw in an old worn sand cut carrier I've got, it runs fine.

I tried a para carrier and it ran better than with the original matched carrier but still not right.

Any ideas as to why?

I set this project on the side about 6 mos. ago and I'm just now getting back to it.

ce · December 13, 2011, 13:49

Bent rat tail

Recoil tube not indexed

Tight rails

Buggered DSA chamber

Bollox DSA gas block

Bagged DSA gas tube

Bogus DSA barrel out of time

Does it extract?

Does it eject?

Does it fail to feed?

**308bolt** · December 13, 2011, 14:35

Quote:

Originally posted by ce
Bent rat tail

Recoil tube not indexed

Tight rails

Buggered DSA chamber

Bollox DSA gas block

Bagged DSA gas tube

Bogus DSA barrel out of time

Does it extract?

Does it eject?

Does it fail to feed?

It fails to feed.
When I get it to feed using the sand cut carrier, it extracts and ejects.
When I use the old, worn, sand cut carrier it feeds fine.
Are tight rails a common problem with DSA receivers?

My only other DSA receiver is on an L1A1 and that one runs fine.

As to rat tail.....OK
recoil tube not indexed.......tried it with para carrier and worked a little better but not right.

What do you mean by bagged DSA gas tube?

ce · December 13, 2011, 16:16

Any manner of gas tube fail, ie; faint threads, missing pin, not screwed in or out enough, flared end

The threads in the gas block may be worn as well, allowing gas to escape before piston has completed the action cycle.

Some carriers are wider than others, so with the stacked tolerance of tight DSA rails, or loaded park in areas, or tool chatter marks, it could bind on the one carrier until something wears down like the old carrier.

Slide it by hand with the action open to find high spots and polish with 500 grit.

Also check the left side rail on the receiver by the ejector block, it should be beveled at the rear and rounded a little on the topside. Feel for the bolt to contact either the left rail or ejector and see if that is sufficient impedance to slow the travel of the bolt and carrier.

Polish feed ramps if there is shaved copper, but only to remove park and not on any edge.

**308bolt** · December 13, 2011, 16:24

The gas tube is the short/Steyr style that's soldered in.

The rails could be the culprit though.

Thanks for the advice.

It gives me a good starting point.

**def90** · December 13, 2011, 16:39

Quote:

Originally posted by 308bolt
Are tight rails a common problem with DSA receivers?

Is this a new rifle/receiver or one that is slightly used? All DSA rifles seem to be tight out of the box.. I assume you have tried to just slide the carrier by itself in the rails, how tight is it when you are sliding it by hand? If this is a new rifle/receiver I would sit on the couch with your favorite show on and work the action until it slides freely. Yes there can be "break in" in these things.

**308bolt** · December 13, 2011, 19:42

Quote:

Originally posted by def90

Is this a new rifle/receiver or one that is slightly used? All DSA rifles seem to be tight out of the box.. I assume you have tried to just slide the carrier by itself in the rails, how tight is it when you are sliding it by hand? If this is a new rifle/receiver I would sit on the couch with your favorite show on and work the action until it slides freely. Yes there can be "break in" in these things.

It is a new receiver.
The kit I used to build it wasn't quite new.
You could see it had been fired but there was no great amount of wear.
The other new DSA receiver that I used was in an L1A1 and I had no problems but when I think about it that kit had substantial wear on it.

C nova · December 14, 2011, 08:29

Check to see if the old carrier is rubbing the top cover/dust cover.

mister2 · December 15, 2011, 07:44

Quote:

....so with the stacked tolerance of tight DSA rails.....

Quote:

there can be "break in" in these things

I think your answer is somewhere in the above. Two more questions: a properly fitted bolt carrier assembly will slide out of the receiver on its own weight, alone; does yours? How many rounds have you shot out of it with new carrier?

My new FAL needed attention on: rails and magazines. Both of my receivers are Imbel and they needed some material removed from the tight rails. My mags had sharp lips that dragged on the cartridge case. So, I shot a couple hundred rounds, smoothed out rails and mags, now everything is fine and running at mid gas setting. It also stopped denting the brass rim and sides.

HTH
MR2

one hand clapping · December 17, 2011, 10:04

+1 on the top of the carrier binding against the top cover. I had a newer DSA I was using do the same thing. the rails were a bit high and the carrier was new with a bit of a extra bump on top. It took me awhile to figure it out. I worked the extra off the top of the carrier instead of messing with the rails, as all else functioned well once I got the carrier to move forward nuff for the bolt to drop.

OHC

**Thomas** · December 19, 2011, 20:21

How do you index a recoil tube?

ce · December 19, 2011, 23:14

There's a relief cut that needs to be at the bottom to allow the rat tail to enter the tube unimpeded. If the tube has worked loose sometimes when it is tightened the cut will be to the side and the tail will bind and short stroke.

Either remove a few threads with a file, or tighten the tube and cut a new relief with a chainsaw file.

Just push in the recoil spring plunger with a rod and you'll see it.

December 13, 2011, 13:26	#1
308bolt Heathen Silver Contributor FALaholic #: 19255 Join Date: Feb 2006 Location: Wisconsin Posts: 19,951	FAL question. Matching Austrian lower, bolt and carrier. New DSA receiver and new DSA barrel. The rifle refuses to cycle using matched carrier. If I throw in an old worn sand cut carrier I've got, it runs fine. I tried a para carrier and it ran better than with the original matched carrier but still not right. Any ideas as to why? I set this project on the side about 6 mos. ago and I'm just now getting back to it. __________________ "The bandwagons rumble past. I sit here on the curb," ~ John Hartford ~ "Nil desperandum, -- Never Despair. That is a motto for you and me. All are not dead; and where there is a spark of patriotic fire, we will rekindle it." ~ Samuel Adams ~

December 13, 2011, 16:24	#5
308bolt Heathen Silver Contributor FALaholic #: 19255 Join Date: Feb 2006 Location: Wisconsin Posts: 19,951	The gas tube is the short/Steyr style that's soldered in. The rails could be the culprit though. Thanks for the advice. It gives me a good starting point. __________________ "The bandwagons rumble past. I sit here on the curb," ~ John Hartford ~ "Nil desperandum, -- Never Despair. That is a motto for you and me. All are not dead; and where there is a spark of patriotic fire, we will rekindle it." ~ Samuel Adams ~

December 19, 2011, 20:21	#11
Thomas Member Silver Contributor FALaholic #: 7451 Join Date: Sep 2002 Location: Central Kentucky Posts: 493	fail to fire How do you index a recoil tube? __________________ Thomas

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December 13, 2011, 13:49	#2
ce Registered FALaholic #: 373 Join Date: Jul 2000 Location: New Mexico Posts: 5,905	Bent rat tail Recoil tube not indexed Tight rails Buggered DSA chamber Bollox DSA gas block Bagged DSA gas tube Bogus DSA barrel out of time Does it extract? Does it eject? Does it fail to feed?

December 13, 2011, 16:16	#4
ce Registered FALaholic #: 373 Join Date: Jul 2000 Location: New Mexico Posts: 5,905	Any manner of gas tube fail, ie; faint threads, missing pin, not screwed in or out enough, flared end The threads in the gas block may be worn as well, allowing gas to escape before piston has completed the action cycle. Some carriers are wider than others, so with the stacked tolerance of tight DSA rails, or loaded park in areas, or tool chatter marks, it could bind on the one carrier until something wears down like the old carrier. Slide it by hand with the action open to find high spots and polish with 500 grit. Also check the left side rail on the receiver by the ejector block, it should be beveled at the rear and rounded a little on the topside. Feel for the bolt to contact either the left rail or ejector and see if that is sufficient impedance to slow the travel of the bolt and carrier. Polish feed ramps if there is shaved copper, but only to remove park and not on any edge.

December 14, 2011, 08:29	#8
C nova Registered FALaholic #: 61228 Join Date: Oct 2010 Location: North Carolina Posts: 261	Check to see if the old carrier is rubbing the top cover/dust cover.

December 17, 2011, 10:04	#10
one hand clapping Registered FALaholic #: 35299 Join Date: Mar 2008 Location: WV mountains Posts: 3,966	+1 on the top of the carrier binding against the top cover. I had a newer DSA I was using do the same thing. the rails were a bit high and the carrier was new with a bit of a extra bump on top. It took me awhile to figure it out. I worked the extra off the top of the carrier instead of messing with the rails, as all else functioned well once I got the carrier to move forward nuff for the bolt to drop. OHC

December 19, 2011, 23:14	#12
ce Registered FALaholic #: 373 Join Date: Jul 2000 Location: New Mexico Posts: 5,905	There's a relief cut that needs to be at the bottom to allow the rat tail to enter the tube unimpeded. If the tube has worked loose sometimes when it is tightened the cut will be to the side and the tail will bind and short stroke. Either remove a few threads with a file, or tighten the tube and cut a new relief with a chainsaw file. Just push in the recoil spring plunger with a rod and you'll see it.