7th Round Stoppage?

[FP1201]

Guys I've got a problem child and I'm about at my wits end.
Well used Garand came into the Shop that had been fed (as stated by the Customer) a steady diet of 180gr. "Hunting ammunition" and the rifle had been fired bone dry enough to start seeing wear, and the forked rod was bent to the point it was contacting the op-rod, so I replaced both, installed a new recoil spring, finished up with a complete cleaning and proper lube with LSA.

First en-bloc of Danish Surplus went through without a any glitches.
Second one would eject, but short cycle, not picking up the next round....all the time I had for the day, and wanted to discuss replacing the Barrel with the customer because the one on it would swallow a case neck and had an ugly Importers stamp in big blue letters.

Installed a new Barrel, reamed & headspaced it, and again the first en-block of M2 Ball went through just like new, next one started skipping (failing to feed the next round) While there wasn't any real signs of wear between the gas cylinder and op-rod piston, I elected to try the two out of another M1 and the first en-bloc went through to I believe the sixth round and stopped with the base still in the enbloc and the bullet tip just out of the receiver, tried it again with the same result.
I also used the spring and fork from the donor rifle just in case the springs were "extra power"

Now at the time I did not have a Micrometer or the dimensions of the Gas Cyl or Piston but do now as found on Lane's Tips. (will check tomorrow)
We checked the recoil spring against two more new ones and the one from the rifle we cannibalized and they were within spec.

I do not have a Timing Block, or Gas Cylinder gauge, but am aggravated enough to buy them unless someone can point out the problem and the solution.
You know '06 Ball has gotten expensive, and I make sure its fully serviceable before returning it to the Customer.

[lyman]

really need the gages,

if you have a micrometer, you can measure the piston, and if you don't have a way to measure the ID of the cylinder, you can improvise that,


something to try, since you don't have a timing gage, is look at the bullet guide,
sometimes the small rounded part where the accelerator makes contact,
sometimes that get some wear an messes things up,
quick fix back in the day was to lay that teat area on a flat part of your vice and whack the sh!t out of it with a ball peen (flat end)

that stretched it enough to make it work

or just replace it,


BTW, I hope you are using Grease, not just LSA

[FP1201]

Thanks, I'll try that.
I'm using the grease suspended in oil on everything including my glasses when firing!

[lyman]

Thanks, I'll try that.
I'm using the grease suspended in oil on everything including my glasses when firing!

grease,,,

not suspended,

[leecork]

The 7th round stoppage problem has been around since the 1940s. I would like to suggest that you take a look on the Internet for a you tube video documented by the Garand Collectors Association. It is called "7th Round Stoppage". It is a well done video that may help you to repair this beautiful rifle.

[Johnny P]

The "Seventh Round Stoppage" existed with the early M1 Rifles, and by serial number range 40,000 had been corrected. While boring the barrel hole the bit was allowed to go too far into the receiver, cutting off the tops of the guide ribs letting the cartridge come out of the clip just crooked enough not to center with the chamber.

[RCS]

photos show a receiver in the 41K serial number range with manufactured low guide ribs. Only
a small percent had the 7th round problem but ordnance decided to repair them as they were
received for rebuild and direct conversion to gas port. Not all were rebuilt as these low rib
receivers can still be found.

About 99% of all the revision 2 receivers were manufactured with high guide ribs and were used
on the last gas trap rifles in the 50K serial range501815018250183

[tanker trash]

The belt of a 300 win mag case can be used as a GC bore gage. measure and select a few different sizes