Is shimming the m14 really necessary?

84wh1

84wh1

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alright, I'm fairly new to m14 and got a question about shimming. I ordered some shims, tried to install them by cutting and sliding over the barrel. However I bent them all and ruined them (oh well, 5$ down the drain). Anyways, after failing at shimming, I started tightening the Gas cylinder lock and managed to get the ting pretty tight by hand (I had to turn it really hard to line it up).

So now if I got it this tight, do I still need shims? The point of the shims is simply to tighten everything up no?
 
nope
not unless your gas ports don't align.
check by slipping the tail end of a 1/16 " drill bit up into the gas cylinders bottom little hole. with piston out of the way, the drill shank should pass clear into the barrel.
if it does, yer good to go
 
U have your gas system too tight, if indeed U had to torque hard it to get it to line up. U should start too feel resistance about 3:30 to 4 o clock. This is what and why U shim, U want a good seal without too much stress on the gas cylinder. Stressing the gas cylinder will ruin accuracy.
 
eaglesnester said:
U have your gas system too tight, if indeed U had to torque hard it to get it to line up. U should start too feel resistance about 3:30 to 4 o clock. This is what and why U shim, U want a good seal without too much stress on the gas cylinder. Stressing the gas cylinder will ruin accuracy.
Click to expand...

I thought the idea was to get it to line up tight enough that you can't push it any further past the block? If I can push the cylinder lock past the gas block, isn't that not tight enough?
 
hand tight at 4 to 5 oclock , tool tight with the gas cylinder wrench at 6 oclock is the normal recommended tightness.
tool tight doesn't mean gorilla tight, but you probably get what I mean
 
Not always necessary, so short answer; your #### won't fall off!

Moose gun / deer gun/ zombie gun/ quad gun .... not always necessary. Obsessive compulsive disorder? By all means we can do the shim so that you can sleep at night. No worries....

Shims are needed to tighten things up when you lock your gas cylinder assembly in place and STILL have the that lock rotate PAST 6 o'clock bottom dead center. My shims are 0.008" or 8 thousandths of an inch and it works out to a shim per "hour" past bottom dead center. :)

Before you M14 lovers start your tirade about how Norc gas cylinders and barrel shoulders are all crap, every single one of my USGI M14 rifles (now 12.5 status) had gas cylinder locks rotating up to 12 o'clock or top dead center. Many of them even cranked all the way past 1 o'clock. :eek:

At a recent M14 clinic for an LE Agency here in Ontario, a TRU Sgt presented an American made M14 type rifle (I'm deliberately being vague here) that had a sloppy (read: plays Jingle Bells) gas cylinder assembly when the lock was at bottom dead center. I showed him how we can still rotate that lock past 12 o'clock and he was alarmed.

So after about trial fitting SIX (M1A from Brownells) gas cylinder locks (all of them being 180'ed also), we found the right / correct/ tight fit and he was in tears. I declared, "No hugging." He coulda passed on Ebola, who knows? Maybe he did not get the October flu shot for H1N4. Maybe his parents were anti-vaccinaters from Toronto NDP pre-dominant ridings? Either way, I did not want my #### to fall off..... :cool:

At the latest clinic or clinic number 60 for me... in Niagara Peninsula, we had a few Norinco locks that turned past 6 o'clock and after 4 people traded gas cylinder locks between them all, everyone was happy except for one dude. Then I broke out my collection of THREE Norinco gas cylinder locks and the third attempt, he obtained a tight fit. :)

Life is good! :wave:

Keep on helping them nooobs!!

Barney
 
When you hit it with the hammer the first time if it doesn't dent hit it again only harder!! LOL, you won't hurt it. I know its hard to get your head around hitting your gun with a hammer but the Norcs like it rough!!!,
 
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buckbrush said:
Why would LEO's be having an M-305 clinic? Surely an AR-10 would be the modern choice? Or is the M-305 next on the prohib list ala the 858 and Swiss Arms?
Click to expand...

I've built well over a dozen m14 type rifles for LEOs over the years and even had range days with a few ;)
none were rcmp, tho I've brought my rifles to range days and ended up shooting several hours with a couple local rcmp guys that thoroughly enjoyed the LRB M25.
 
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