View Full Version : FnFAl BBL problems
June 24, 2007, 15:31
Any one know where I can buy a match grade bbl for my Belgain made FN-Fal in 308. The I bought the gun 1978
Seems that the compensator that I had on it went south and a gunsmith cut my bbl and made a new compensator, Now the gun that was 1 MOA is now not consistant. It will put the first 2 shots 1/2 MOA then the third and subsequent shots are 4inches away and then anywhere but where they should go.
I have narrowed it down to the gun....I think
I have used match ammo, changed scopes and used a one piece mount and checked the crown etc everything seems as it should...she just doesn't shoot well anymore and can no longer use her in 3 gun competitions.
the bbl now is 20 1/4" long and muzzle threaed to 9/16 24 tpi.
so I guess I need a new barrel unless someone can come up ewith an idea to help
June 24, 2007, 19:00
"Made" a new compensator?? When there are so many available on the market today?? And why did he chop your barrel, instead of simply silver soldering the old comp off??
I'm surprised you got such consistent, deadly accuracy out of your FAL, it certainly isn't that kind of rifle from the basic design. It may have been a fluke of your previous barrel. However, if you are that serious about this, you probably won't want a new stock barrel, or even the so-called "match" offerings from DSA. I would contact a professional barrel maker and have them machine up a custom replacement. A pro should be familiar with the FAL specs, although you could also send them your existing barrel to use as a pattern, I suppose.
June 24, 2007, 19:20
thnx for the reply. I had a Benny Hill compensator on it aqnd it worked just great.
I think badger makes the DSA bbls.
June 24, 2007, 19:32
the compensator isnt off center is it??
It seem that in theory at least, if it were just a degree or two off center, as it heats up, maybe it will "pull" the barrel thus changing POI, and or barrel harmonics.
yea, I just made all that up as I was typing, BUT it sounds logical :biggrin:
June 24, 2007, 20:25
How does it shoot without the compensator?
June 24, 2007, 20:32
I have a G1 that works quite nicely without anything on the end of the barrel. Groups actually open up with the flashhider in place. Oddity of that particular rifle. Somewhat disappointing as I shot it for a few years while the ban was in place, and had looked forward to finally putting the flashhider on it as FN intended.
Now that I can unscrew these things, I have an StG that shoots WORSE without the flashhider. These things are weird. Each rifle is unique.
June 24, 2007, 21:11
Again thanx for the replies tne degrres off of center sounds logacal because the first 2 shots are 1/2 inch group then the third is like 4'' to the right then it really gets bad as if it really does heat up.I'll try to talk to the gunsmith
June 24, 2007, 22:50
I'm sure gigglllleeeee will be on shortly to comment about how you need to have your barrel recut and line bored.
June 25, 2007, 10:10
On really close scutiny of the comp I found some copper on the 9 oclock position. sooo that means some thing is out of round. Now is the bbl cut poorly or the comp out of round??? we will find out.My gunsmith will hear about this one.
June 25, 2007, 16:37
why not ..what tha hell do you think it is .maybe it was the baby jesus ....al gore .....gravity .....stupidity /???...im thinkin the latter
..is the lock shoulder the same ...??? if it is the smurf didnt turn the shoulder to realign the barrel (kinda like they do it at the factory) ...when are you flatlanders ever gonna figure this out ..my god !! ....line boring of parts that need to be straight has been done the same way for 400 years ....why do you want to change to the inncorrect method ....????
here is the tip ...gettin your barrel cut ??? magik marker the shoulder before you send it out...or scribe a line on it ...if its still there when it gets back ..your smith may be just a joker with a lathe ...no experience ...or just ask the procedure ..or ask if he has a tube testing fixture ...a qualified machinist will ....
premtive for radio ..just shut up and play some zeppelin he he
larry ...cool target stobe unit in your website ..i always hear he clank at 5-6 but that would be great for hearing impaired folk ..great idea ..
June 25, 2007, 17:08
just shot the gun at noon........8 inch group without the compensator and in a triangle shape....really bad. I look at ther muxzzle and it looks ok but what the hell do I know i'm just a veterinarian not a gunsmith or machinist
DS arms told me they can put a match barrel on the gun what do yoiu guys think???
thanks for the info ggiiiietc......i'll do it
June 25, 2007, 19:23
H*ck. Put the compensator back on and only fire two round strings. If you can put the first two into 1/2" at 100 yds, it (whatever it is) won't be getting up again.
All kidding aside, it sounds as though you should go talk to your gunsmith. ggiilliiee has a point about marking before or asking how the work was done after. Are you sure that that barrel is more than hand-tight? 8" at 100 yds doesn't sound good enough to be even bad barrel harmonics.
June 25, 2007, 19:33
Something is wrong with this post.
I don't believe you when you say the gun was 1 MOA before all this started. You had the greatest FAL of all time if that statement is true.
Second, you say you bought the gun in '78. Was it shooting 1 MOA in '78 and with every type of ammo you have fired in it since then - well, at least until the "gunsmith" got hold of it?
When is the last time you shot a 1 MOA group with that rifle?
What kind of ammo did you use then?
What kind of sights did you use then?
How many shots are you firing to determine this MOA measurement?
What sights are you using now?
What kind of target are you firing at?
Are you firing from the same location and firing support as you previously fired those 1 MOA groups?
Are you now using the same ammo as you used for the 1 MOA groups?
June 26, 2007, 03:31
Originally posted by ggiilliiee
premtive for radio ..just shut up and play some zeppelin he he
Way Down Inside
CHORD ----- CHORD
June 29, 2007, 23:25
OOOTAYYY. I am a machinist and toolmaker but even I would be cautious about this problem. Dies, moulds and guns are quirky things. If the threads were cut even a little off center the pressure of the round coming out could change the trajectory due to expansion or warpage from heat. However did the GGG. crown the barrel properly after the recut? If the barrel was off center when he did his work you can bet that the bullet path will be altered. Is every thing tight and or installed properly? Dirt or a burr, or misalignment will do strange and infuriating things to accuracy and function. Loose thread fit would allow some movement or allow some when the barrel heats up after the first rounds are fired.
A radius left at the bottom of an otherwise square shoulder can hold mating parts off and allow unwanted movement at the joint. Did the GGG undercut the threads at the shoulder or relieve the suppressor by chamfering the mating end to assure a square fit? Mere thousandths of an inch in the gun translates to inches and feet downrange.
Check the crown first. Borrow a set of Dial or Digital calipers and see if you can measure between the lands of the rifling. If you can and there is a difference in 180 degree measurements the threads are most likely cut off center. The flash suppressor will be off center. Another way would be to use a precision gage pin or plug slid in the bore (0.0005 of an inch or 0.02 mm.) to do the same measurement by placing the back end of the calipers on top of the threads and sliding the head backwards to get the measurement. Are Fal barrels the same diameter most of their length? Use the calipers to check the barrel diameter. If it is the same use a square to see if the end was cut square. Hold a penlight on the other side of th square and see if light can be seen at any point of the flats at the end of the barrel, with the square base firmly on the barrel.
OK. Enough food for thought. Check it out and let us know.
July 05, 2007, 18:09
Sounds like a re crown is in order here. Don't mess with the barrel unless there is serious damage.
On second thought, replacing it with DSA barrel seems like a pretty good idea.
I will even step up to the plate to take that nasty original Belgian HB off your hands to help defray the costs of replacement.
How much do ya want for it? I'll even pay extra for the handguards
July 06, 2007, 22:57
Global warming is the cause of your problems. Just ask Al Gore.
July 08, 2007, 21:58
Wel I did use the same rests and did use the same match ammo and did change scopes to be sure there was only one variable. Used the same rests and used JP targets etc at 100yards and tried to be ssure that it was indeed the bbl. I shot it with and withut the comp and let it cool etc.
Good news is I went to a garage sale and found 2 Austrian uppers with 21"bbl and they were new if you can believe that. the gas pistons were like mirrors ...now I have too many variables on what to do, What nice problem.
I think I'll have some FAL armorer cut the bbl on my Belgium 308 match gun and recrown it and see what hapens and make 2 more guns from all the parts.
any replies or suggestions e-mail me at firstname.lastname@example.org
July 08, 2007, 23:02
ta check the barrel ..put it in the lathe between centers ..make sure the lathe is on line (to check line put a piece of barstock in between the centers ..turn od on both ends to a set reference off the dial indicator ...pull ten off each end ...measure both end to check for taper ...(angularity ...not the large south american pig with tusks )he .....with this known ..run the bbl in between centers and put a dial on the bbl shoulder face ...and check runout ...if its running out your screwed for accuracy .....bbl face has to be re-faced to get perpindik.......and headspace can/ will change slightly...re check it ...gets it back to the way the factory did it ...if you just cut .....and reinstall ....i hope your inherently lucky .....or not shooting farther than 200 yds ......dam i should be charging ya $65.00 hr fer this ....:wink:
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