Original caliber M1 Garand

[Mike Irwin]

Pyro powder apparently gave a very high initial pressure spike followed by a rapid drop off, which was why the primer activation worked so well.

The later IMR powders had a smoother, longer pressure curve.

 

[TEDDY]

M1

the M14 went to a box mag because of the change to automatic.the auto ended as a mistake with the power of full size cartridges.frankly I like the enblock clip.since military ammo comes from the factory in clips the statement of ending as a single shot is meaningless.the gun is much faster to load.having one caliber in war is far better than like Italy with several.
example 6.5/7.35/303/8mm breda/and 10 mm.

 

[Voyageur]

"Is that in Hatcher's Book of the Garand? I do not see mention of primer pocket crimps in Hatcher's Notebook."

Yup... that's where it is Jim. pp. 74-5. I picked up the book (way back when) because I was interested in the development of the military semi-automatics. More specifically, I was looking for information on the Pederson .276, the Thompson semi-auto rifle and the Remington (Browning) Model 8. I was surprised to find the Hatcher semi-auto rifle as I never knew if even existed. I had seen a reference to the Hatcher 'Garand' book and sought it out.

The short stroke of the 'primer actuated' firearms was interesting but I could not believe that the production quality control could be close enough to be 100% reliable. Part of this was based upon actual experience, part on the fact that you paid 'extra' for 'match' primers and articles written on primer wall thickness in magazines such as Handloader.

 

[KLRANGL]

Forgive the ignorance, but how exactly does primer actuation work? Ive never heard of it before, and a quick google search came up empty...

 

[Voyageur]

KLRANGL... I am including info on the 'primer actuation' principle along with the Garand that John C. designed. A schematic is available and I will post it, if you like, but it is quite difficult to read.

You should know that, along with the 'primer actuation' style, another type the 'Bang' principle, which involves a sliding muzzle cap, was also being investigated by the Ordnance Department.

If you would really like an education of the first totally reliable semi-automatic and full automatic firearms... hie down to the local library and pick up a copy of John M. Browning, American Gunmaker. I read this book about once a year for true inspiration.

Here is the information you asked for along with Browning's first semi-auto: