Garand Seating Depth

[jr_roosa]

I was inspired by a previous thread to actually measure the jump to the rifling in my Garand, a CMP special grade with a new criterion barrel, 1600 rounds through it so far. At maximum magazine length, I wasn't close to the rifling, but I though if I could squeeze a little more accuracy out of my slow fire loads by playing with the length. I got the Hornady setup with the modified case.

To seat with a 175gr Sierra Match King at the lands puts me with only 0.15" of the bullet in the case. Bummer.

Anybody else out there ever measure your Garand chamber? Do they all run long?

Fortunately the SMKs are reported to be happy with a long jump. I'll try mixing it up a little anyway and see if I find a sweet spot somewhere in there.

-J.

 

[USSR]

J,

The throats are way out there on all my Garands which have original barrels. I simply seat my bullets so there is one full caliber (.308") inside of the neck, not counting the boattail.

Don

 

[jr_roosa]

I figured the old ones were long, but I was hoping that they cut the chambers on the criterion barrels differently. Guess not.

-J.

 

[P-32]

I would give the 155 gr Palma SMK bullets a try. They shoot pretty dang good out of all of my service grade '06 Garands with a dose of IMR 4064, in a GI case and a CCI primer. Bullets are loaded to mag length. My load will hold the 10 ring at 600 yards in my correct H&R with it's LMR barrel. I have not shot the load at 600 with the other service grades I have but shot the 155's out to 200 with the others and they will go where I call them. I have one lowly field grade I've been working on but have not shot the 155's out of this rifle yet.

 

[30Cal]

I've found all the SMKs have the same distance to the lands for a given OAL. Haven't checked the 155 since they changed the recipe, but since it's got a higher BC, the jump will probably be worse.

Go with USSR's advice.

 

[rodregier]

Just keep in mind that some VLD projectile designs don't delivery good accuracy with a large jump to the throat...

 

[P-32]

I can only report about my rifles.

 

[jr_roosa]

Thanks guys,

Interestingly, I've been seating to an OAL of 3.300 for the 175 SMKs and when I sat down and started measuring stuff, that only has about .250 in the case or so.

I think I might try a few and single load them way out to the lands and see what happens and incrementally work back to where I am now. It will be about .150 of the bullet in the case.

I have a funny feeling that after all of this messing around, I'll be back to my 3.300" OAL loads that I started with.

-J