How and where to add M14 shims?

Too bad you missed Hungry's clinic in Smiths Falls ON this weekend. He had the shim stock and cutters. The whole afternoon someone was hammering and smacking out shims. But you missed it.

To answer your question, Marstar has sold them over the years and they go between the barrel shoulder and the back of the stock ferrule. One or two will usually do to help time the closing position of the gas cylinder lock from 4 o'clock first pressure to 6 o'clock tight.
 
maple_leaf_eh said:
Too bad you missed Hungry's clinic in Smiths Falls ON this weekend. He had the shim stock and cutters. The whole afternoon someone was hammering and smacking out shims. But you missed it.

To answer your question, Marstar has sold them over the years and they go between the barrel shoulder and the back of the stock ferrule. One or two will usually do to help time the closing position of the gas cylinder lock from 4 o'clock first pressure to 6 o'clock tight.
Click to expand...

Thanks but I already bought the shims from Marstar but I'm looking for some actual pics as to where they go and I don't understand this timing thing? Why isn't there any videos? lol.

Aren't there ever any clinics in the Toronto area?
 
There are clinics in the Toronto area. Just PM Hungry, as he generally knows best as to when and where he is doing clinics. :p

Installing shims is easy. There are two ways to do it. If you can pull off the flash hider, pull everything forward of the stock ferrule off of the barrel. There should be a machined lip on the barrel. That is where the shim(s) go. Put one or two on, test fit.

The second way is less ideal. If your flash hider is welded on, cut the shim at a 45 degree angle, and then slip it around the same shoulder as the first method, without pulling everything off of the barrel.
 
Jacks_username said:
There are clinics in the Toronto area. Just PM Hungry, as he generally knows best as to when and where he is doing clinics. :p

Installing shims is easy. There are two ways to do it. If you can pull off the flash hider, pull everything forward of the stock ferrule off of the barrel. There should be a machined lip on the barrel. That is where the shim(s) go. Put one or two on, test fit.

The second way is less ideal. If your flash hider is welded on, cut the shim at a 45 degree angle, and then slip it around the same shoulder as the first method, without pulling everything off of the barrel.
Click to expand...

Could you take a pic of this machined lip you speak of?
 
Ill do my best to make it to your house this week, I promise, its pretty simple when you have done it before.

Pm Hungry, as he is the guy we will go see in april ;) if your looking for videos
 
carsmovies said:
Could you take a pic of this machined lip you speak of?
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By my tape measure, it is 8 1/4" from the crown at the muzzle and 13 5/8" from the breech. To describe the shoulder, it is sloped on the rear and has a lip about 1/8" which the gas cylinder fits against.

The shims are thin flat "washers". There is nothing magical about them, except that they work by moving the gas cylinder forward a few thousands of an inch so the gas cylinder lock snugs tightly without backing off from the 6 0'clock position.
 
Is it meant to go between here?

Hungry here: Nope, not there.... pull the entire gas cylinder and front band forward. That exposes the shoulder on the barrel where the entire gas cylinder assy sits up against. I just held a clinic in Barrie on 16 Jan 2010!

IMG_0754.jpg




And it's designed so that when tightening this down it doesn't go around far as in this video?

 
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carsmovies said:
Is it meant to go between here?

IMG_0754.jpg




And it's designed so that when tightening this down it doesn't go around far as in this video?

Click to expand...

NO ! - go farther back
The shims go between the front band (FERRULE PLATE) - [the metal plate at the end of the front of the stock with the metal lip going over the bottom of the stock ferrule] and the barrel shoulder. This is for alignment for the gas port only. The gas port must be aligned properly for proper functioning of the gas system.After installing the gas assembly and front band, tighten the gas cylinder lock on the gas cylinder. The lock will probably stop past the 6 o'clock position. After tightening the lock, back it off to 3 o'clock, check with feeler gauges to see what shim thickness is needed when you snug it back up with the feeler gauge still inserted to the 4 o'clock position.Don't back up the cylinder lock more than a whole turn as it will throw off the alignment with the gas port. The lock should be snug at 4 o'clock so when turned to 6 o'clock, it securely clamps the loose front band.
swingerlh.gif
 
chopper 1 said:
NO ! - go farther back
The shims go between the front band (FERRULE PLATE) - [the metal plate at the end of the front of the stock with the metal lip going over the bottom of the stock ferrule] and the barrel shoulder. This is for alignment for the gas port only. The gas port must be aligned properly for proper functioning of the gas system.After installing the gas assembly and front band, tighten the gas cylinder lock on the gas cylinder. The lock will probably stop past the 6 o'clock position. After tightening the lock, back it off to 3 o'clock, check with feeler gauges to see what shim thickness is needed when you snug it back up with the feeler gauge still inserted to the 4 o'clock position.Don't back up the cylinder lock more than a whole turn as it will throw off the alignment with the gas port. The lock should be snug at 4 o'clock so when turned to 6 o'clock, it securely clamps the loose front band.
swingerlh.gif
Click to expand...

Sorry but I'm completely lost unless I see a video to guide me. How do you know if the gas posts are lined up perfectly?
 
carsmovies said:
Sorry but I'm completely lost unless I see a video to guide me. How do you know if the gas posts are lined up perfectly?
Click to expand...

4 oclock and six oclock should be lined up.

Take the gas piston out and stick a tiny allen key in the hole at the bottom of the gas cylinder and if it pokes up into the barrel you are good to go.
swingerlh.gif
 
-DeerStalker- said:
As mentioned the shim doesn't go there. It would cause a gas leak if you shimmed it there.

You need to slide your gas cylinder off and install the shim behind, not in front of it.
Click to expand...

So front the front end:

1 unscrew the castle nut screw
2 loosen the castle nut and slide the flash suppressor off the barrel (assuming it isn't welded, which is another set of problems)
3 unscrew the gas plug
4 un"wind" the gas cylinder lock, counting the number of turns and remove
5 slide the gas cylinder off the barrel
6 slide the stock ferrule off the barrel, thereby exposing the shoulder where the shims go.
7 slide one or two shims down the barrel, seating snuggly

reassemble in reverse order
 
maple_leaf_eh said:
So front the front end:

1 unscrew the castle nut screw
2 loosen the castle nut and slide the flash suppressor off the barrel (assuming it isn't welded, which is another set of problems)
3 unscrew the gas plug
4 un"wind" the gas cylinder lock, counting the number of turns and remove
5 slide the gas cylinder off the barrel
6 slide the stock ferrule off the barrel, thereby exposing the shoulder where the shims go.
7 slide one or two shims down the barrel, seating snuggly

reassemble in reverse order
Click to expand...

Finally figured it out. Thanks.
 
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