Norma 203B in M1 Garand

While we're waiting . . . .
Y'all might want take a gander at Slamfire's take....
>
> 50,000 psia breech pressure requirement almost became a moot point.
> Breech pressures would always be less
>
 
If Garands are limited to 30 caliber ammo with pressure in the 4X,000 psi range, what about the ones chambered for 7.62 NATO ammo producing 60,000 psi or more? Their proof loads are over 80,000 psi. In 1954, Frankfort arsenal used CUP systems to measure pressure.

SAAMI doesn't list this rifle-cartridge as an unsafe combination. They know what the safety limits are for what's involved.
 
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All that's nice, but the fact remains -- even the TM says 50,000psi for 30-06 M2 Ball

The 7.62 NATO pressure problem is all over the map in terms of what/where we're measuring apples-to-apples
http://mil-spec.tpub.com/MIL-C/MIL-C-46931F/MIL-C-46931F00005.htm
It takes the old CUP-to-PSI conversion problem and drops into a graduate-level mixmaster

And this hasn't even yet gotten into the SAAMI vs CIP (and now EPVAT) test measurement setup differences
https://en.wikipedia.org/wiki/Small_arms_ammunition_pressure_testing

Or are you saying that Full-Up commerical 150gr/3,000fps_muzzle 30-06 ammunition is OK for the Garand ?
(actually 2,990fps on the Winchester box box when I bought in 1970. Hornady now advertises near 3,100)
 
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Full-Up commerical 150gr/3,000fps_muzzle 30-06 ammunition is usually okay for the Garand.

So was commercial 30-06 match ammo with 180 grain FMJBT bullets leaving about 2600 fps.

The MIL SPEC link in post 23 is confusing CUP with PSI. There's no precise conversion formula for one to the other.

Have you ever compared SAAMI 30-06 PSI and CUP pressures?

ANSI-SAAMI-Z299.4-CFR-Approved-2015-12-14-Posting-Copy-1.pdf
 
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That's one exception to my comment full-Up commerical 150gr/3,000fps_muzzle 30-06 ammunition is "usually" okay for the Garand. There are others.
 
Here's todays data:

Loaded a clip ( :D ) with five rounds of the Sierra 150gr/IMR4895 Load shown below,
topped off w/ three rounds of HXP`65 for reference (as "standard" M2 Ball).
Also used HXP`65 brass (fired) for water volume of 69.8gr H2O

55° day, but kept rifle in car/clip in coat pocket until set up/loaded (assume 70° std)

Did not load 50gr 4895 as as per TM, but rather 49.0 grains after reading Slamfire note again.
(after all, we were only going after an initial test point from which to adjust)

Set the LABRADAR's 1st range point at 25yds to meet TM's 2,750fps @ 78ft peg point.
Target at 50 Yds (simply because the last time I'd shot the rifle I'd used/left the sight for 100 yards using Cast bullets)

RESULT:

The three as-issued HXP`65 M2 Ball rounds averaged what they always do:
2,749 (Muzzle), 2,681 (25 yds)

The IMR 4895 Loadout results w/o comment:
(other than there are 8 bullet holes)

Garand-Test-at-M2-Ball-150-Sierra-SBT-IMR4895-49gr-sm.jpg
 
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mehavey said:
Here's todays data:

Loaded a clip ( :D ) with five rounds of the Sierra 150gr/IMR4895 Load shown below,
topped off w/ three rounds of HXP`65 for reference (as "standard" M2 Ball).
Also used HXP`65 brass (fired) for water volume of 69.8gr H2O

55° day, but kept rifle in car/clip in coat pocket until set up/loaded (assume 70° std)
Did not load 50gr 4895 as as per TM, but rather 49.0 grains after reading Slamfire note again.
(after all, we were only going after an initial test point from which to adjust)
Set the LABRADAR's 1st range point at 25yds to meet TM's 2,750 fps peg point.
Target at 50 Yds (simply because the last time I'd shot the rifle I'd used/left the sight for 100 yards using Cast bullets)

RESULT:

The three HXP`65 M2 Ball rounds averaged what they always do:
2,749 (Muzzle), 2,681 (25 yds)

The IMR 4895 Loadout results w/o comment:
(other than there are 8 bullet holes)

Garand-Test-at-M2-Ball-150-Sierra-SBT-IMR4895-49gr-sm.jpg
Click to expand...
Those are some great details , very interesting . I like that you included the HXP data . I have a bunch of it . Quick question, is the HXP worth reloading ? I have some saved for a rainy day, have not tried to size/prep it yet. Thanks
 
The U. S. taught Greece how to make the ammo and helped set up their ammunition manufacturing. So it should be no surprise that it mimics U. S. arsenal ammo quality.
 
It really does seem to be good stuff . I annealed a bunch and sized it , very happy with what I see quality wise . Thanks for the info .
 
mehavey said:
Here's todays data:

Loaded a clip ( :D ) with five rounds of the Sierra 150gr/IMR4895 Load shown below,
topped off w/ three rounds of HXP`65 for reference (as "standard" M2 Ball).
Also used HXP`65 brass (fired) for water volume of 69.8gr H2O

55° day, but kept rifle in car/clip in coat pocket until set up/loaded (assume 70° std)

Did not load 50gr 4895 as as per TM, but rather 49.0 grains after reading Slamfire note again.
(after all, we were only going after an initial test point from which to adjust)

Set the LABRADAR's 1st range point at 25yds to meet TM's 2,750fps @ 78ft peg point.
Target at 50 Yds (simply because the last time I'd shot the rifle I'd used/left the sight for 100 yards using Cast bullets)

RESULT:

The three as-issued HXP`65 M2 Ball rounds averaged what they always do:
2,749 (Muzzle), 2,681 (25 yds)

The IMR 4895 Loadout results w/o comment:
(other than there are 8 bullet holes)

Garand-Test-at-M2-Ball-150-Sierra-SBT-IMR4895-49gr-sm.jpg
Click to expand...
What are your test barrel's bore and groove diameters to 4 decimal places?

If larger than arsenal test barrel specs, velocity and pressure numbers will be smaller.
 
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I'd rather give you the truth. Facts, if you prefer

MIL-P-3984J AMENDMENT 3 says it's 60,000 psi. Same as SAAMI's specs.
 

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