[jrswanson1]

I got a 7x57 FN-49 back in December. I took her out to the range in January, and the brass was flinging out like she was a CETME. I finally got the handguards off last month and adjusted the gas setting. The last owner had it set all the way over to the left and it appears it was seriously over gassed for the PP ammo I have. After adjusting the gas block all of the way to the right, the brass is only going 6' away, not 30'. However, the extractor takes a nice chunk out of the rim, and she vacillates ejecting forward and back, mostly back. Is this normal? I'd really like to reload the brass after shooting. Thanks.



Jim

 

[sprint10]

I have two FN49's and both tend to be hard on the brass on extraction.

 

[LVSteve]

What ammo are you using? It might have a long pressure curve that even the adjustable system cannot deal with. Been there, done that with a FAL and an 8mm FN-49. You cannot use slow powders in these gas guns as they were designed around medium to fast rifle powders.

 

[Mashwamp]

I handload for my Venezuelan and the brass does take quite a beating. I get the big divot on the rim and a small sharp ding just south of the neck ,brass doesn't always land in the same place.....It's not as exciting but some time I flip the gas cylinder plug off....defeats the fun of a semi....but keeps the brass perfect.........

 

[jrswanson1]

I'm using Prvi Partisan 139gr soft point ammo. How do you turn the gas off? I may not be setting the gas correctly.

Jim

 

[1911crazy]

Remember the gas port when its all the way open the gas system on the FN49 gets less gas to operate it. The gas port exhausts the excess gas away from the gas system on the fn49's. The more the gas port is closed the more gas pressure is sent to the gas system. If its ripping the rims on the cases you may have too much gas going to the system to operate it.

The Egyptian hakim, the egy rasheed and the svt40 tokarev ect. the gas valve adjusts how much gas the system gets to operate it. These are different gas systems so my point is don't get them mixed up.

 

[LVSteve]

Here is what I wrote regarding an Egyptian FN-49 that was tearing up brass.

Case rim damage implies TOO MUCH gas to me. The piston is trying to open the action while there is still a bunch of pressure so the case is hanging on to the inside of the chamber while the extractor is hauling on the rim. It could be that the pressure curve of your ammo simply will not work in an FN49.

You might find that Prvi 7mm uses a powder too slow for the FN-49 gas system regardless of how you adjust it. The FAL has the same style gas system and is unusable with Winchester ammo with the red X on the box. Ejection is aneamic and yet the rims are still tweaked. This is sure sign that there is still substantial pressure while the action is trying to cycle.

Perhaps another 7mm user can chime in if they have used Prvi with no issues. The visual check is less gas = more holes exposed. You should start from there. BTW, when it was throwing brass into the next zip code, were those rims damaged too?

 

[Mashwamp]

Turning the gas cylinder off is done by rotating the gas cylinder plug(in front of front sight- marked A & R) 180 degs. This keeps all gas from getting to the gas adjuster( port) and makes the rifle,a single shot only.adjusting the gas port to different settings may or may not help the rim situation . Burn rate of the powder may not be compatable with the guns gas regulation ability.I'm pretty sure I shot Privi in the past but I don't remember having any trouble with it.
I would try more adjustment , if no desired results perhaps a different ammo,I haven't seen much other than Privi thats readily available and affordable though.....hope some of this helps......