FN 49 Ejection Issues and Brass Crunching

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I'm having a bit of a problem with my FN 49, in 8 mil.

When it ejects it seems very keen on crunching up the brass, which makes it rather unsuitable to reload. An issue I find, as, 8 mil is not cheap.

I've tried to dial open the gas port, as far as it goes, but I still have crunchy problems.

What I'm wondering is, is it the ammo? Too hot? Would hand-loads done at a lesser velocity and power have any effect?
 
Well, dam good question ! I have a FN49 in 7mm and it totally tears up the neck on ejection ! Have yet to figure it out. One person told me, but I haven't found the time to try it, was to shut off the gas and fire off one round and eject it manually to see how it is and then very slowly open the gas until it just cycles and recheck. Hopefully this will work, but again, I haven't had the time. let me know how you do !
 
HIGHRPM said:
Well, dam good question ! I have a FN49 in 7mm and it totally tears up the neck on ejection ! Have yet to figure it out. One person told me, but I haven't found the time to try it, was to shut off the gas and fire off one round and eject it manually to see how it is and then very slowly open the gas until it just cycles and recheck. Hopefully this will work, but again, I haven't had the time. let me know how you do !
Click to expand...

That's what I tried to do... open it all the way to vent as much gas as I could... but didn't have any luck with it. With the port closed, all the gas gets shunted back to the piston, as far as I'm aware.. which probably won't help much...
 
If the rims are getting torn up, the gas is set to high... if your getting damaged brass even with a lower setting, the ammunition you are using might have a powder that burns to slow for the gas system to adjust to. I've heard PPU has this problem, but I have never used PPU in my 49' to see it for myself. I use 50's yugo with no problems and have used FNM, modern S&B and 70's romanian with no issues.
 
David1974 said:
If the rims are getting torn up, the gas is set to high... if your getting damaged brass even with a lower setting, the ammunition you are using might have a powder that burns to slow for the gas system to adjust to. I've heard PPU has this problem, but I have never used PPU in my 49' to see it for myself. I use 50's yugo with no problems and have used FNM, modern S&B and 70's romanian with no issues.
Click to expand...

I'm having this effect with S&B. I'll have to try PPU, and if that fails, expariment with hand loads.
 
Smellie gave me some good info on ammo, one thing he mentioned was to reload and use a fast powder. Im sure he will be along in a bit and give a good bit of info.
 
I've shot a fair amount of PPU 198gr 8mm out of my FN-49. Gas port fully open and the rifle cycles flawless. The brass doesn't get munched or torn but I do notice small dings 3/4 of the way down where they seem to be bouncing off the receiver. The brass is kicking out 10-15 feet. I suspect that the PPU powder, as mentioned above is a slower burner or is a pretty hot round. Haven't tried any other ammo in it yet to see how it functions.

 
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Semi-automatic rifles such as the FN-49 depend upon a certain amount of gas pressure AT THE GAS PORT to function correctly. A powder that is too fast or too slow will give malfunctions when the cartridge is fired. It can also stress certain parts of a rifle, (M-1 Garand bent operating rods is one example) when the wrong burning rate powder is used, particularly in handloads. Lighter or heavier bullets than originally Military loads will also cause malfunctions, along with bullet types (round nosed or large lead exposed.) As mentioned, different manufacturers use different types of powders.
 
I wish we had a better description of what the beast is doing, something better than "crunching" the brass.

"Crunching" brass just is NOT in The Book!

If the RIMS are distorted and the brass is flung wide of the rifle, then there ACTION is getting TOO MUCH GAS and the Gas Bleed needs to be OPENED.

If the case MOUTHS are flattened and/or the SHOULDERS BADLY DENTED, the problem (and solution) are the same.

If the Rifle is EXTRACTING a casing and then trying to jam it BACK INTO THE CHAMBER ON TOP OF ANOTHER ROUND, then the Action is NOT GETTING ENOUGH GAS, in which case the GAS BLEED will NEED CLOSING PARTWAY.

The IDEAL situation, from the standpoint of BATTERING and FELT RECOIL as well as ACCURACY, is with the brass JUST being ejected from the Action and lying on the Bench beside you.

Hope this helps.
 
If saving the brass is a major concern with the store bought ammo available to you, reverse the position on the gas vent in the gas plug so no gas reaches the piston and use it like a straight pull. Once fired brass should be pretty pristine that way for later reloading.

The S&B 196gr. is on the hot side. maybe too hot for this semi.
Heard it woks well in MG34 &42.
My FN49 worked well with the anemic 170gr Winchester SP
 
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HIGHRPM said:
Well, dam good question ! I have a FN49 in 7mm and it totally tears up the neck on ejection ! Have yet to figure it out. One person told me, but I haven't found the time to try it, was to shut off the gas and fire off one round and eject it manually to see how it is and then very slowly open the gas until it just cycles and recheck. Hopefully this will work, but again, I haven't had the time. let me know how you do !
Click to expand...

Had to do that with my Vennie. Works like a charm.
 
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