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thefurball
10-01-2007, 5:49 PM
First of all: Yes, I used the search button.

When tightened by hand the barrel 'times' to the 11:00 position as noted in all the posts I can find, both here and on the FAL Files site. When I apply torque with a wrench the barrel stops short of the 12:00 position required. It appears that the breech face is bottoming out on the inside of the receiver too early. Should I:

1) Shave down the breech face;
2) Shave down the inner portion of the receiver that is making contact;
3) Get a bigger wrench to apply the Gorilla Grip method of fine gunsmithing, or;
4) Send it off to a gunsmith that knows what the heck he is doing.

I just would like to hear if anyone out there has come up against a similar situation and hear how you got past it before I bring out the heavy equipment and risk unsightly tool marks (more unsightly tool marks actually) on an otherwise nice looking firearm.

Thanks!

thedrickel
10-01-2007, 5:57 PM
Are you 100% sure the barrel is bottoming out on the inside of the receiver? Color the barrel shoulder and breech with a black sharpie and see where it rubs off when you screw the barrel in.

How much torque are you applying and how far from 12:00 are you? What is your tooling like, sounds like you are using a receiver wrench to hold the upper and using a wrench on the barrel flats?

More than likely I would take some material off the barrel and not the receiver, but even then only if it is significantly short of 12:00. If <5 degrees I would torque it home. Do you have any other barrels you can try, to see if the barrel or upper is out of spec?

IH8CALAWS
10-01-2007, 6:16 PM
how much before 12:00 does it stop?

thefurball
10-02-2007, 7:13 AM
Stops at about 11:30.

4 Brigada
10-02-2007, 7:44 AM
First question .What receiver are you using? What are you using to tighten the barrel, barrel vise and receiver wrench or receiver wrench and wrench. What torque value are you using, if using a torque wrench and are you using the receiver wrench and setting your torque at 100 foot/pounds , you are exceding the torque value due to the longer arm, and by the way that torque value is just an example, military setting is 125, If you are not using the torque wrench look inside the receiver at the barrels breech, is it shaving metal of the barrel? Also did you prepare the receiver there could be some imperfections on the receiver that isnt permiting the barrel to reach full depth, if this the case send it to a qualified FAL gunsmith, Allthough that area is not highly stressed, better safe than sorry.How many times have you put the barrel on? On some recievers you need to chase the threads. And is the barrel a new barrel or a kit barrel. if its a new barrel I wouldnt start shaving anything off right off the bat specially if its a new and name barrel (FN licensed or DSA). Ah one more thing are you using antisieze compound on the threads?

Here is the formula: M1 = M2 x L1 / L2

Where:

M1 is the torque setting of the wrench.

M2 is the actual torque applied to the barrel

L1 is the normal length of the wrench

L2 is the extended length of the wrench (Length of torque wrench + length of adapter/receiver wrench)

Example:
M1=torque wrench setting ?
M2=80 FT-LBS (Desired touque)
L1=18" (Legnth of torque wrench)
L2=22" (Total length of wrench with 4 inch extension added to wrench)
80x18/22=65.45 M1 therefore = 65.45; In otherwords if you want to torque a fastener to 80 FT-LBS using an 18 inch torque wrench with a 4 inch torque extender you will set the wrench to 65.45 FT-LBS

If the torque is with compound, and your not using it your wasting your time, same goes in reverse

Citadelgrad87
10-02-2007, 9:11 AM
I used a dedicated barrel block in a vice at a machine shop, a BIG vice.

Then I took the largest crescent wrench I have ever seen, the jaws were 3+ inches, and snugged it in, then I took a 4' cheater bar and put it over the wrench, then I torqued.

You don't need to go crazy with pressure, but it is a very snug fir.

BTW, mine timed about 10:20-10:30, shy of 11, and I have no trouble.

thefurball
10-02-2007, 9:14 AM
- What receiver are you using: Enterprise. Good, bad or indifferent it is what I have to work with.

- What are you using to tighten the barrel: Receiver wrench and wrench on the barrel flats.

- What torque value are you using: Two good grunts worth. I'm an old farm boy, besides, I'll be darned if I could figure out how to get a torque wrench on the darned thing.

- If you are not using the torque wrench look inside the receiver at the barrels breech, is it shaving metal of the barrel: Not shaving metal, but I think this is where the problem is. There seems to be a small defect in the receiver where the face of the breech should seat. (Looks like their mill flinched a bit.) It makes contact at the one point and has a couple of thou clearance otherwise. The shoulder of the barrel is making good even contact all the way round.

- Also did you prepare the receiver: Other than a visual inspection for obvious flaws and clearing out the threads, no. I took the manufacturer at their word that it was good to go.

- How many times have you put the barrel on: First time, and I stopped when I hit the snag rather than chancing 'operator induced failure' in the receiver.

- And is the barrel a new barrel or a kit barrel: Kit barrel, new receiver.

- Ah one more thing are you using antisieze compound on the threads: Indeed.

As this is my first FAL build, I am also a little concerned as to how much lateral torque the receiver can take where it seats in the receiver wrench. It sure looks to me like I could cause all sorts of problems if I am even a little bit overzealous with the wrench.

Thanks again for the input.

thefurball
10-02-2007, 9:16 AM
I used a dedicated barrel block in a vice at a machine shop, a BIG vice.

Then I took the largest crescent wrench I have ever seen, the jaws were 3+ inches, and snugged it in, then I took a 4' cheater bar and put it over the wrench, then I torqued.

You don't need to go crazy with pressure, but it is a very snug fir.

BTW, mine timed about 10:20-10:30, shy of 11, and I have no trouble.

Perhaps I'm just being a bit overly cautious... I HOPE so.

4 Brigada
10-02-2007, 9:38 AM
Hey Furball talk to Matt at Entreprise they are really helpful Im sure they could clean that up for you in jif and you know it was done to factory specs by the manufacturer themselfs, win win situation. That receiver wrench is made to handle/contain the loads caused by the barrel installation.Does it look like this? Also that 12oclock might be 1159 30 or 1200 05, need to align or like some call it "time the barrel" there are different methods to do that, but you sould be using ine when your installing a barrel. You need to use a torque wrench, You dont know how much stress your putting in that area threads/chamber area the gouging on the face of the breech would be the least of your problems if that area cracks, You would have a barrel launching/plastic surgery performing gun. NOT LEGAL TO OWN IN CA. That I know cause the FAL receiver "IS ALMOST ILEGAL" and it would have the other 2 most evil features barrel launching/plastic surgery performing.


http://i159.photobucket.com/albums/t155/4brigada/DSCF1016.jpg

duenor
10-02-2007, 10:51 AM
Hiya Furball,
Take some good up close pics and send them in an email to Matt (matt(at)entreprise.com) along with a description of what you are trying to do.

Please do use the proper tools - 60,000 CUPS is like a grenade in front of your face if things are not done properly.

thedrickel
10-02-2007, 11:19 AM
I think this is where the problem is. There seems to be a small defect in the receiver where the face of the breech should seat. (Looks like their mill flinched a bit.) It makes contact at the one point and has a couple of thou clearance otherwise. The shoulder of the barrel is making good even contact all the way round.

It sounds like the receiver is out of spec. Do you want to wait a month by sending it back and waiting for them to fix it (grind down the flaw) or send you a new one with the same serial # (or a different serial # that you will have to DROS again)? Just grind down the high spot on the inside of the receiver and torque it home, 11:30 is almost there.

No need for a torque wrench. Countless homebuilt FALs have been built without them, and the only ones launching barrels are CAI builds.

I will . . . try . . . to withhold my comments about EAI's rough machining.

4 Brigada
10-02-2007, 12:08 PM
Thedrickel, the ones you build you dont use a torque wrench? Even though the FN tech manuals specify to do so? What is it that you do? Crack that area on any receiver and see what happends, need to know how the breech. barrel and locking shoulder work to see how it would. BTW you can rent a torque wrench not buy one, generally the WEG guys find out that it adds a whole 5 dollars to their 250 dollar collection of parts. If it has to be done why not do it right. "If you have a 5 dollar head buy a five dollar helmet" Bell Helmet Ad

thedrickel
10-02-2007, 1:29 PM
The actual # of ft-lb's is irrelevant. If the barrel hand-times to 10:30-11:00 there is no way you can torque it home with insufficient force. There are many, many threads on the fal files dealing with this issue. For example: http://www.falfiles.com/forums/showthread.php?s=&threadid=195562

If it was a problem, people's FALs would be launching barrels left and right.

thefurball
10-02-2007, 1:32 PM
Ok... the clouds are starting to clear. I think I just need a bigger hammer, or specifically a different hammer.

The wrench shown in the post by "4 Brigada" is far different than the one I am trying to use. Mine has heavy shoulders which causes the wrench on the barrel flats to canter out, which in turn reduces contact between the barrel and wrench, which in turn leads to slipping as I apply torque. (I also note the nifty 1/2" hole in the wrench which allows the attachment of a torque wrench.)

So, if I CAREFULLY remove the minor burr on receiver face and change to a more user friendly wrench I should be good to go.

Thanks again for all the input.

vandal
10-02-2007, 1:40 PM
You are using barreling grease on the threads, right?

4 Brigada
10-02-2007, 1:55 PM
The actual # of ft-lb's is irrelevant

The issue here is not that its under torqued, its not timing. Thefurball was right. How did he realize that there is something wrong with the receiver? because a MKI eyeball the torque and the barrel wasnt timing, if he used the proper torque he would have eliminated that factor right off the bat, becase with the proper torque the barrel was no reaching the timing point. What you suggest is to keep wrenching on it, until hell be dammned it will time?. Im sorry I cannot in true conciense recommend that, as well g't yer dremril make a holi there, I once had a M1A receiver, test fitted the parts, the bolt wasnt sliding right in the receiver I looked and saw ther was a slight imperfeccion on the rear bar, being a rear lugged very expensive receiver I sent it to my smith to assemble figured he would fix it, He sent the receiver back unserviceable unrepairable, I said nothing a little dremel and some stonework could fix well its a good thing he knew what he was doing if I would have done that would have more than likely fired out battery at one point. Get my point if you dont know dont fixit yourself. Manufacuturer changed it out no new waiting period it was damaged unuseable, got it in the mail to my house. BTW Gunthings.com or a guy on the FALFILES ratas calientes have good wrenches mine is from gunthings

thedrickel
10-02-2007, 2:08 PM
The issue here is not that its under torqued, its not timing. Thefurball was right. How did he realize that there is something wrong with the receiver? because a MKI eyeball the torque and the barrel wasnt timing, if he used the proper torque he would have eliminated that factor right off the bat, becase with the proper torque the barrel was no reaching the timing point. What you suggest is to keep wrenching on it, until hell be dammned it will time?. Im sorry I cannot in true conciense recommend that, as well g't yer dremril make a holi there, I once had a M1A receiver, test fitted the parts, the bolt wasnt sliding right in the receiver I looked and saw ther was a slight imperfeccion on the rear bar, being a rear lugged very expensive receiver I sent it to my smith to assemble figured he would fix it, He sent the receiver back unserviceable unrepairable, I said nothing a little dremel and some stonework could fix well its a good thing he knew what he was doing if I would have done that would have more than likely fired out battery at one point. Get my point if you dont know dont fixit yourself. Manufacuturer changed it out no new waiting period it was damaged unuseable, got it in the mail to my house.

In no way did I recommend "keep wrenching on it, until hell be dammned it will time". What I am saying is that, if the receiver and barrel are IN SPEC, you can torque it home and it doesn't really matter whether you used 90 or 150 ft-lbs to do it. If the receiver is obviously out of spec, some corrective action needs to take place. But you have to consider the source of the parts, the wait involved, the nature/difficulty of the problem and whether you can fix it yourself. If the receivers I received from EAI were fixable, I would have fixed them. You can't buy a low-cost, low-quality FAL receiver and not expect to have to "hand fit" it a little.

You are correct, the original poster's issue was the barrel was not seating properly. But his course of action depends on a lot of factors, the least of which is having a torque wrench or not.

My first post in this thread, in which I recommended torquing it home if <5 degrees short, was before the actual source of the problem was known to me. Now that I know the receiver is out of spec, I of course would fix it instead of risking damage to it and the barrel.

4 Brigada
10-02-2007, 2:43 PM
We are in agreement, on the issue of what was the problem. But look at if from another angle you call me and say the barrel isnt timing I ask you where is it and at what torque? MMMM dont know the torque? could be just tight receiver, see what I mean, same scenario I torqued it 125 ft/lbs and its a 1130 then stop and check for and the laundry list follows. Easier on everybody, plus its the proper way to do it. Glad we could help him

CRTguns
10-02-2007, 2:47 PM
Once a barrell has been installed and removed a numebr of times, like on the case of an old military takeoff barrel, the "crush" factory becomes much less. The metal on the threads becomes compressed and burnished, makes them time short.

Trick- get some 800 on up to 1200 grit SiC lapping paste- put it on the threads and shoulder... turn the barrel in by hand- turn it out, turn it in, clean it all up, then re-install with grease on threads (cheap grease- the kind that will break down after time). 3 or 4 in-outs with lap paste will move you about 5 degrees each time. it seems to scar up the surface to allow it to crush again.
;)

-hanko
10-02-2007, 3:15 PM
thedrickel is correct...factory books indicate a torque number, but if the barrel HAND times to 1100 you will be able to wrench it home & meet the torque spec. If you can't wrench it to 1200, one of 3 things is happening"

1. Your tools are at their limit...you NEED a barrel vise and receiver wrench to do it right. Most of my guns I could clock with a 1/2" breaker bar that's 18" long. You can get by with a crescent, but then you're trying to hold the receiver wrench in a vise...if you need to do that, drill the vise for 2 3/8" dowel pins and drill your vise jaws to match.

2. Barrel shoulder is interfering with the front of the receiver...standard fix is to slowly remove metal from the shoulder until you can time the barrel.

3. Threaded end of the barrel is hitting something in the receiver...standard fix here is to slowly file or grind material from the receiver until it clears the barrel.

hth

-hanko

4 Brigada
10-02-2007, 3:33 PM
From the Fal Files thread AR KABOOM,

I quote

"Went to my favorite pawn shot today (one of my firends works there) and he had the upper from an AR that he got in. Looked to be a modified Oly upper

He'd fired 5 rounds out of it, then wondered why he couldnt feel his hand, and his foot was bleedin with a pile of ammo on it. Blew the bottom of the mag out.

Wolf polymer coated steel case. no fault of the ammo.

Some dumbass from what I can tell tried adjust the feed ramps/polish the chamber and took a chunk out of the bottom of the chamber. Literally an 1/8" inch of completely unsupported case.

Case blew out the side a mm or so above the extractor grove.

Bubbah needs banned from gunsmithin.

Upper will now get uses for a 22LR conversion"

"any questions on dremdril holi righgt dare"

Its a new receiver did he get it for free?. No. its not right. he sends it in at entreprise they will fix it in 2 seconds, guys are super helpful there. If we get a new vette and the trunk dont open we break out the crow bar? Its his first build, how much does he take off what if his hair is a brown one, instead of a blond, what if he sneezes at that moment, yeap turn in the receiver and say hey I was just trying to fix it? Good Advise why dont we show/write how to do it the right way and then let people figure out how to change it themselfs.

-hanko
10-02-2007, 6:36 PM
.............snippted............
Its a new receiver did he get it for free?. No. its not right. he sends it in at entreprise they will fix it in 2 seconds, guys are super helpful there. If we get a new vette and the trunk dont open we break out the crow bar? Its his first build, how much does he take off what if his hair is a brown one, instead of a blond, what if he sneezes at that moment, yeap turn in the receiver and say hey I was just trying to fix it? Good Advise why dont we show/write how to do it the right way and then let people figure out how to change it themselfs.
I'd take/send it to E'prise if it were mine, but that wasn't the original question

If he knows the rear of the barrel is not interfering with the receiver, it's either send the barrel AND receiver to E'prise, or remove a little material from the barrel shoulder.

Both barrel and receiver need to go to E'prise because one needs fitting to the other...even if E'prise guarantees their receiver is in spec, what do they reference their spec to?? OP is using a barrel from one gun and trying to fit it to a new receiver. Lemme' know if I'm wrong, but the only receiver mfr that uses licensed drawings is DSA. Not sure if E'prise reverse engineered a receiver to get their specs or what.

If he needs to remove metal from the barrel shoulder, the "right" way to do it is to know each full turn of the barrel moves it 1/16" in relation to the receiver. If the gun hand times at 1100, it's 30 deg. short of seating and just a little more than 0.005" needs to be removed from the shoulder. Simple and done all the time.

The corvette analogy doesn't hold water...we're not talking about a completed gun here, just the receiver (maybe a barrel also, perhaps). If the spare trunk lid you bought for your vette didn't fit, you fit it yourself;)

-hanko

duenor
10-02-2007, 7:26 PM
Evening, gentlemen - 7:20pm here.

Furball has been PM'ed and assured that EAI will stand behind their product. If he chooses to accept our offer, I will personally ensure that it is examined and returned within a week or so, even if I have to ship it myself.

Thank you, Brigada, for your vote of confidence. And if you get another complete commercial FAL kit like you did before, do let me know. I'm still kicking myself for not buying that $600 kit you had a month ago.

4 Brigada
10-02-2007, 7:30 PM
Duenor,
There was never any doubt for me about the service or the quality of the Entreprise parts. Win win scenario the best kind. Im kicking myself for selling the lower for what I did, a guy had one for sale stripped in the files for 200. Now I cant find one like it. live and learn

4 Brigada
10-02-2007, 7:57 PM
Furball says When tightened by hand the barrel 'times' to the 11:00 position as noted in all the posts I can find, both here and on the FAL Files site. When I apply torque with a wrench the barrel stops short of the 12:00 position required.

Before you get into the problem solving mode. Know what the problem is its the first step to helping someone. thats were the barrel is suppose to time at by hand, then torqued it should at or very close to 12 the final torque of about 125 lbs, but the tru indicator is the relation with the front sight so torque might be less or a little more, This is what furball couldnt get, because the grinding has nothing to do with the threads, it is also a used barrel so it may be a little out of perfect specs. And using the grind off based on that formula would a WAG at best, WAG WEG AR KABOOM. Thats why respect gunsmiths

thefurball
10-03-2007, 4:20 PM
Broke out the Sawsall this afternoon and 'modified' (severely) the shoulders on the receiver wrench. Suddenly I have all sorts of access to the barrel flats! Imagine that .

The burr on the receiver side turned out to be a small bit of metal that had folded over during milling. The slightest touch with a Dremel tool and it was gone.

So the plan for tomorrow is: Properly seated receiver wrench; properly seated barrel wrench; no burrs or excessive shoulder material; and torque appropriately.

I'll post a picture of the finished product.

.

Matt@EntrepriseArms
10-07-2007, 7:11 PM
Wow, I just happened upon this thread. As Duenor stated, we are always willing to help. As I have discovered since I started working at Entreprise arms, all surplus barrels are ever so slightly different, and can cause all sorts of grief when trying to figure out why they do or don't like to fit.

Of course, we do our best to turn out well finished receivers that can accept the wide variety of barrel sizes out there. If there is a burr or flaw in our receiver, I would like to know about it!

thefurball, would you mind pm'ing me the serial number on your receiver? I would like to see when it was made, and get some insight into that particular production run.

-hanko
10-08-2007, 6:03 AM
This is a fair explanation of barrel timing issues when assembling a kit...

http://www.falfiles.com/forums/showthread.php?s=&threadid=214131

Please post when you get her together;)

-hanko