Anyone familiar with Browning BAR ?

[alpha6164]

I own a an FN FNAR which is a .308 semiautomatic made by FN. It is basically the BAR with a pistol grip and cold hammer forged barrel but the action is all BAR. I sent my rifle to a gun smith to have the barrel threaded for a muzzle brake installation, and after i have received my rifle back it will not cycle.

It has basically turned my rifle into a bolt action. I know Browning themselves that had the BOSS system as a muzzle brake. I dont think it is the muzzle brake that is the root cause. I believe that during the barrel removal and assembly something is not installed correctly and not allowing the gas system to operate correctly.

Anybody familiar with the workings of the BAR that can shed any light i would highly appreciate it. Thanks.

Here is a video of another member with an FNAR with the same muzzle brake without having any issues.

http://www.youtube.com/watch?v=vwGFhThFOBE

 

[TexasRifleman]

No experience with the FNAR but I have a BAR Safari I've hunted with for a long time.

I do not know if the BAR gas system is identical to the FNAR, but here's a link to the BAR manual that shows some good photos of how it all goes together.

I am assuming that you can manually cycle the bolt, it just doesn't cycle with gas pressure when fired?

The BAR has a rotating bolt head sort of like an AR15. The gas port in the barrel allows the gas into a cylinder and then when the right pressure is reached it pushes the piston back.

At least on the BAR there is a gas setting adjustment screw on the gas cylinder and it's always recommended to leave it the heck alone Any change to that can do exactly what you describe, basically make the gun a bolt action since it lets all the gas blow by. I don't know but I guess it is possible that adding the brake has changed the amount of gas available for cycling and that might need to be changed.

Maybe not what you have, but at least it's something to look at to start with. And it may be as simple as it was put together incorrectly. Or, there could be some gunk blocking the gas flow, metal shavings possibly?

It's a pretty straightforward and reliable system so I can't imagine it's anything horrible. Good luck, let us know what you find, I'm somewhat interested in one of those rifles and I'd like to hear what you think of yours.

http://media.browning.com/pdf/om/bar_98355_om_s.pdf

 

[alpha6164]

Yep it is pretty much identical. The only thing i see different is that in the BAR manual it asks you to unscrew the gas cylinder screw cap before the piston is removed where in the FNAR it does not mention that and not necessary.

Here is the FNAR manual let me know what you think:

http://www.fnhusa.com/le/manuals/FNARownersmanual2008.pdf

 

[TexasRifleman]

Do you have the gas adjustment set screw on the cylinder? I'd check that to see if it was loose.

At least from fooling with my BAR over the years I don't see how the rifle could be put together wrong so that it would still cycle manually and fire. Has to be gas related it seems to me.

I assume the barrel was removed for the threading, that would be my first guess is that something got in the gas port. I've never had the barrel off so I don't know how hard it is to align the gas port but that might be possible too.

I'm with you though, has to be gas related.

 

[alpha6164]

Yes, the barrel was definitely removed to be threaded. Yes, it has the same gas adjustment screw. Last night i went to the range and adjusted the gas screw 1/2 turn out at a time, until it was almost about to fall out with no change. Then i started back at the original position, and turned the screw in 1/2 turn at a time making three full turns and still made no difference. Here is the picture of the gas block and screw on the FNAR.

 

[Sock Puppet]

Hmmm...I thought the gas adjustment screw would fix it. You may want to post on the FN board in the FNAR section.

 

[TexasRifleman]

There must be either something blocking the gas port or the barrel isn't aligned with the gas port on the gas block.

i'm guessing the barrel was installed but not properly aligned with the gas block.

I can't think of anything else.

 

[rcmodel]

Dup post in Gunsmithing I answered this morning.
http://www.thehighroad.org/showpost.php?p=6203573&postcount=2

Since you have already screwed the screw, I'd go along with a blocked gas port.
Seems most likely the guy stripped the barrel to get it in his lathe, then didn't get the gas port holes lined up when he put it back together.

Be aware that if the port orifice screw is adjusted wrong it will either not cycle, or break something, one or the other.

rc

 

[alpha6164]

I dont know if this helps or not but how is the gas port supposed to be aligned with the gas block? I spoke to the gun smith and he said that he never took off the gas block cause it appears is silver sodded. So could it be out of alignment if the gas block was never taken off the barrel?

When i unscrew the bottom screw (allen screw) all the way out and i shine a flash light there, and look in the barrel i do see light coming in the barrel. I just dont know how much more aligned it can be or maybe not aligned all the way but still allowing some light to get in the barrel?

If the silver side screw is taken out and you shine a light down in there, you dont see the light it in the barrel, but you do see a glimmer of the light in the gas block looking from above.

Also there is a tiny tiny screw on the exact opposite side of the silver side screw. This appears to be a locking screw that locks the silver screw in position cause they do meet in the middle. Neither side screw touch the allen screw in the middle.

Needless to say, i tried every combination. With both the side screw and allen screw all the way in, one of the backed out one turn at a time, both of them backed out at the same time one turn at a time, and none of them made the gun cycle. All inputs appreciated.

 

[Bill_Rights]

Alpha,

Let's back up here a moment. Why put a muzzle brake on the FNAR in the first place? It is only a .30 caliber full-power rifle round, and the overall weight and action of the gun make it a mild-recoiling sweet shooter that can be aimed right through the recoil disruptions. You certainly don't need a muzzle brake to protect your shoulder. I am an FNAR shooter, so I know whereof I speak.

Please explain your thinking.

Meanwhile, have some fun tearing into the action yourself and see if you can find the mis-assembly problem or clog. I guess you know about the YouTube video on this?

One diagnostic that would be helpful would be to live fire the rifle and see if the piston is cycling. Unfortunately, you can't just take off the fore-stock and watch the linkage move because, dang it, the forestock is necessary to hold in-board the twin thrust bars that transfer piston motion about a foot back to the bolt. Otherwise (w/o stock) these can just fall out due to gravity. If you could figure out a way to temporarily retain these thrust bars, then you could live-fire-cycle the action with the fore stock removed. It wouldn't take much. The inside of the forestock only serves as a sideways retainer, taking none of the longitudinal force of the bolt cycling thrust itself. Or maybe you could just tape a little piece of paper to the thrust block up front and let the paper poke out between the barrel and the re-installed fore-stock (unless it is too tight a fit). If the slip of paper slides back toward you when you live fire, the piston/thrust block up front is working and you have some problem more rearward, in the transfer linkage or bolt area itself.

And YES, like someone else recommended, do post your problem on the FNAR portion of the FN user forum http://www.fnforum.net/. Those guys are great and know a lot about this particular rifle.

 

[alpha6164]

^^^
Thanks for the reply Bill. I installed the muzzle brake for the same reasons guys that have AR-15s put muzzle brake on theirs. Primarily to have rapid follow up shots. As nice of a shooting the FNAR is, doing double taps etc are still more difficult because you do come off target. For tactical purposes or hog hunting, i would like to be back on target as fast as possible, or even better never come off the target. Check out this video of the FNAR with the PWS brake:

http://www.youtube.com/watch?v=vwGFhThFOBE


You cant do that without the muzzle brake. I have posted on fnforum.net but the only reply i have received was to adjust the gas screw which has not helped. I have narrowed my problem to the piston. I went to my dealer yesterday and he had a FNAR in stock and i removed the foregrip and compared to mine and everything is installed properly. The only difference is that with the dealer one when i slide the bolt back, i can pull the piston out of the gas block about 1/2", on mine the piston does not come back. So i am assuming that if the piston is frozen that there is no way it can hit the inertia block to cycle the round. So i am going to take it apart, clean it and go from there.

 

[61chalk]

Could you, or have you tried shooting a different brand of ammo? Perhaps try
something with higher velocity, a faster burn powder...this would create a little
more pressure an might make it cycle......worth a try?

 

[Bill_Rights]

Alpha,

Yeh, I watched the video. You are correct, muzzle climb is minimal in that video, even when firing about as fast as the action will cycle. I am a 240 lb man with strong upper body, so maybe I can just overpower the muzzle climb on mine. As you know, but to explain to bench shooters, we are talking dynamic aiming here. In other words, as the recoil disruption throws you off your sight picture, you are already anticipating that and moving the sights back down (and left or right, for a moving target) for the follow-up shot. You squeeze off that second (or third) shot as the sights cross the target, still moving. No static sight picture; this is not sniper work. Obviously, this works only for scope with low magnification and large field of view, or, more likely, a 1X reflex sight such as the EOTech holographic. The FNAR comes with no provision for iron sights. There is a constant hub-bub among users as to how to best accomplish getting iron sights on an FNAR, even if only as BUIS for the superior aiming technologies mentioned.

About the repair, sounds like you're onto it. If you need me to pull mine out and check any other aspect, write again.

 

[dogrunner]

Alpha, I own three BARs.....not the FN model you cite, but the gas system is identical. Those gas systems do vary from the first model BAR to the third. The third, which you have, dispenses with the gas bleed off valve in the piston block cap (front of the piston housing).....and substitutes a direct bleed off thru the piston itself. That screw supplies the amount of constriction necessary per caliber.

Might I suggest you pull that piston completely out and inspect the bleed hole itself into the piston chamber.........as you described it, you shined a light thru the screw hole & saw light....it seems to me that its likely you've a blockage its between that point and the piston housing itself. Be sure to check that piston for free travel as well.

Kinda surprised at your difficulty as all my rifles (two '06s & a .338) have functioned with just about anything I've chambered in them, and I shoot handloads exclusively. Only problem I have ever had was damaged buffers, but that's entirely a different matter and relates to my use of relatively slow powders.

 

[Bill_Rights]

Alpha,
By the way, I do recall that others on the FN Forum, FNAR area, have said that there are a couple of components in the piston slide rod/return spring area that can be re-assembled both ways on the rod or rod base. However, it does matter which way they go. I forget the deets. I was just going to lightly mark components with a Sharpie as I dis-assembled them. The details are on the FNAR section of the FN Forum, but their search function is poor to (maybe actually) non-existent.

 

[Havocsquad]

Edited/removed comment due to an old thread.

 

[LoonWulf]

hey everyone i have been googling this for months seems to be the closest thing i can find, so i got my barrel cerkoted last month and the gas screw on the side (that browning says never take out) was taken out, its a safari mk2 300 win mag with the boss can some one please help me set this screw up. this was my old mans gun and try to keep it alive

You may want to post a new thread with the specific question.
But from my understanding, having never actually goofed with the gas system on a BAR, you turn the screw all the way in closing off all flow, then back it out till the gun will reliably cycle your chosen load.

Like i said.ive never done this on a bar, but thats how i adjust any other gun with an adjustable gas system.

This also only applies to bars with the adjustment screw on the side. And if you change loads you may need to adjust the system again.

 

[RainDodger]

Simplest solution first - it is possible to install the gas piston backwards. In that case, the rifle will be a single shot. The action will not cycle. Make sure that little piston is installed the right direction!

(If you have not yet messed with the gas adjust screw (it should have red paint on it), DON'T mess with it. Your gunsmith should have had no reason to turn it at all.)