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Old 05-13-2011, 09:12 PM
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Default First installment; general requirements for a Match-rifle

A service-grade or better rifle is almost a necessity to build an accurate match rifle. The reason for this is because not every part has a NM equal and a Service-grade will give you servicable parts. I'll go over the major parts in a general sense so you can get the idea behind what I'm saying.

Receiver- First of all, you want the highest Serial-numbered Receiver you can get for several reasons. First, SA went through over 35 revisions on the Garand receiver over it's service life some were for manufacturing ease, but most were improvements. Second, by getting the highest S/N possible you get a receiver with alot less wear on it. The Garands' gas-system is very robust and this causes wear on the receiver, mainly through constant battering of the bolt on the receiver recesses. A newer receiver has less wear and is thus easier to set-up.

Barrel- Here's the thing with barrels, it not only has to have close to minimum ME(Muzzle-Erosion) and TE(Throat Erosion), it has to be straight. A NM Barrel with a ME over 2 is a shotgun in competition. Likewise with a TE over three or four. Well, you think 3 isn't much for the Muzzle. At 300 yards it'll turn Xs into tens or nines. Now, this doesn't mean Military barrels are unsuitable. The best Match-rifle I've built to date has a VAR barrel. That's made by the Danish Military arsenal. But, SA or LMR Barrels, made in America can be just as good.

As for being straight, what good is an accurate but slightly bent or non-cencentrically bored barrel if you have to use most of your sight adjustment to get it Zero'd at 200 yards? A Barrel that requires more than 12 clicks of elevation or windage to zero at 200, will run out of adjustment at 5 or 600 yards.

Okay, those are the important two things. The rest depend on condition. I'll tell you now, 95% of Military stocksets are useless for a Match-Rifle without extensive bedding/rework. We're going to use a Commercial Stockset for this rifle. The bolt and triggergroup may be usable, the entire gas-system is going to be replaced, as are the front and rear sights.

I'll start breaking things down more in detail in the next installment.
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Old 05-23-2011, 07:31 PM
Grizzman Grizzman is offline
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Please explain the reasoning behind replacing the entire gas system while building a match rifle.

All the rest makes complete sense.

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Old 05-31-2011, 12:52 PM
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The two most important components in a Garand, as far as operation are concerned, are the Gas-Cylinder and the Operating-Rod. These are also two items with high wear. A Gas-Cylinder that measures .530, while fine for a service-grade, leaks too much and won't last very long in a Match-Rifle. An unissued Gas-Cylinder will measure .528 at the port-chamber. This make for a better seal with the Op-Rod piston and more consistant operation. Plus, there will be modifications done.

Operating Rod. First, not all Operating Rods are created equal. The late 77-Series Op-Rods made by Remington and Springfield Armory are superior to other Rods in a Match-Rifles for several reasons. One, the bends are tighter, this makes for less chance of rubbing or vibration as therse Op-Rods hold closer to the barrel.Two, The piston is better shaped and a more chip-resistant Stainless Steel.Three, most of the 77-series Operating rods are marked NM because the piston diameter has been miked and cerified by the Stamping as being .5256". As you can tell, the clearence is tighter. Much better seal. A Gas-Cylinder measuring .530 and a .525 or 4 piston will allow more gas to escape around it and cause more uneven wear as the rifle ages.

The biggest secret to accuracy, repeatable accuracy, in a M1 Garand is consistantcy of operation. Everything doing as close as possible to exactly the same thing every time.
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Last edited by Dave Waits; 05-31-2011 at 12:57 PM.
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Old 05-31-2011, 10:13 PM
Grizzman Grizzman is offline
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I was just thinking that since it's gonna leak, it wouldn't matter too much whether it leaks some or leaks a lot....as long as it leaks consistently and cycles every time.

I didn't even think very hard on the other aspects of the op rod.

Thanks for the schooling.

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