Technical: Gas System endurance test

[Dano]

Just for grins, I took my Imbel FAL out the range today to see how many rounds I could fire, without cleaning, before I would have to adjust the gas to keep it cycling.

I was shooting my 147gr FMJBT, LC Brass, 42gr of IMR4895 loads. Gas was set at its normal setting (the Imbel gas ring doesn't have numbers on it like the STG)if it had numbers, I'd say it was set on about 6-6.5 like my STG.

I was practicing my standing off-hand aimed fire position. I was shooting at an 8" gong at 100 yards. TASCO Red dot sight. I was able to hit the gong 9 out of 10 times. No brag, just wanted to let you know it was aimed fire and not just blasting away.

There was about 2-4 seconds between each shot with timeouts to reload mags and police brass. So the rifle was getting warm, but not hot because of the cooling between mags.

So how many rounds do you think I was able to fire before an adjustment to the Gas ring was necessary?

Give me your best guess.

Answer to follow...

[derek huffman, azexarms]

I've gotten in excess of 700 rds through my post-sample MGs before the piston starts to bind from so much carbon. yeah. D.

[Dirtfarmer]

112 rds.

Goodwill,
-Dirtfarmer

[Dano]

Keep in mind that I'm only talking about having to "adjust" the gas and not a complete stoppage.

Derek - 700 rounds sounds pretty good for full auto!

The rifle started out at around 6-6.5, so I had plenty of adjustment left to keep it going. This question is just about having to perform the "first" adjustment.

I'll give you a clue... I was impressed.

[Chipmunk]

125rnds
Chipmunk

[CSAcavalry]

300 rds

[Dano]

Some more clues:

derek huffman - high
Dirtfarmer - low
Chipmunk - low
CSAcavalry - low

[hksigwaltherXglockXSA58]

227

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- Ron V.

[Scott S]

My guess is that you ran out of ammo before an adjustment was necessary. Maybe 500 rounds? Did you have help loading mags?

A couple weekends ago I put about 500 rounds of milsurp, mostly Hirt, thru my DSA with no stoppages, no gas adjustment, and no cleaning. I did have to adjust the gas system at the start of the 500 rounds, but that took a mere 4 or 5 shots from the first mag. After 500 or so rounds my milsurp ammo supply was exhausted, so switched to a mag with some Winchester Power Point alternated with various unfired milsurp I found on the range (it was a machine gun shoot, so there were plenty of unfired rounds about). Before I shot that mag, I *opened* the gas adjustment one click to compensate for the Winchester commercial stuff. Whole mag ran without a hitch, and rapid fire at that.

[fal_shooter]

492

[Dano]

hksigwaltherXglockXSA58 - low
fal_shooter - high
Scott S - high and no I didn't run out of ammo.

So now we know it is somewhere between:
CSA's 300 and fal_shooter's 492.

[Molon_Labe]

My guess was 400 before I got to the bottom of the thread and i'll stick with it...

[Dano]

OK, I've got to give to:

CSAcavalry - 300
and
Molon_Labe - 400

The actual number was **** 350 ****

I was pleasantly suprised with both the endurance and accuracy. Accuracy didn't seem to suffer much, I could still ring the gong 9 out 10 shots after over 300 shots were fired without cleaning.

Man, are you folks gonna like your group buy Imbel kits!!!

[AR-45ACP]

Hmm,My STG went through 36 mags of RG and SA in 1 day no stoppage,no adjustment gas on 4.5 correctly set as per manuel and trust me we weren't being really nice to it or anything http://www.fnfal.com/forums/biggrin.gif

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The first ones expensive,but after that,they're all free.

[Ratlord]

I shoot 300-500 rounds in a day without any gas adjustment or cleaning and have no problems whatsoever. This is in the Kali desert so there is added sand in the rigging. My gas is set to 4 or 5 (I think 5). I'm using an Entreprise standard STG. with a type 3 receiver.

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"It's not the Earth the meek inhertit, it's the dirt." -Mordred, "Camelot"

Mark
San Diego
ratlord@nation-of-rats.net

[JohnnyMac]

In addition to variances in specific FAL's and different ammo types, I imagine that temperature and humidity have an effect on how badly / how fast the gas system gets fouled.

I'm fairly new to the world of military semi-autos, but I've been shooting black-powder muzzle-loaders for years. When shooting with real blackpowder (not Pyrodex), fouling generally stays soft and "greasy" in high humidity, while dry conditions will produce hard caked-on residue. Alot of competitive BP shooters (both ML and cartridge) blow into their rifles after each shot, so that their moist breath helps keep the fouling soft.

The reason I mention this, is that a FAL gas system that fouls to the point of needing adjustment after 500 rds in Arizona (dry), may do better or worse when shot in say western Washington State (moist).

JMc

[Dano]

Keep in mind that the gas was adjusted just to the point of holding the bolt open and then closing it down a click. Around 6-6.5.

Had I started at around 4-4.5 I'd probably still be shooting.

The lesson I learned during this exercise is that it takes ALOT of ammo before powder residue starts to slow down the cycling of a FAL.

I think it says quite abit about the weapon's reliabiliy.