Marine low number receivers

[Sunray]

...in the receiver where the locking lugs seat..." Is not a head space issue. Head space is an in the chamber only tolerance.
"...a field test bolt..." No such thing. It's proper head space gauges or nothing. No bits of tape. Empty cases, chewing gum, feeler gauges or anything else.
As I recall, the U.S. Ordnance Dept.(not U.S. Army Ordnance) via the U.S. Army didn't have that many receiver failures either. The whole issue is covered in its own chapter in Hatcher's Notebook.

[Cosine26]

"field test bolt-no such thing".
What is this from Brophy?
https://imgur.com/VEx8b6p

Scans of my FTB

https://imgur.com/CWr2Ofd

https://imgur.com/u3IdRFA

Marked "U.S.Rifle M1903 - Field Test Bolt- C2065- Ord DPT U.S.A - NYTG

[pickax]

Found this post by "slamfire" in an old CMP low number '03 thread.


#37 Report Post
Old 03-28-2010, 08:45 PM
Slamfire Slamfire is offline
Join Date: Feb 2010
Posts: 110
Default
Quote:
The DHT wasn't a perfect creation either, always wondered why SA didn't convert to NS when RIA did, it was a much better rifle all the way around in my opinion.
Hatcher was always positive, never negative about anything the Army ever did. It was always to infinity and beyond. He portrays the DHT as a great Army triumph, one cannot help but read the section and not go away with the impression that the DHT receivers were the strongest most perfect creation in the history of the world. This strong impression is carried over to the extent that any failure of a high number receiver is taken with disbelief. Everyone tries to explain DHT receiver failures as being transition SHT , or maybe the numbers were wrong, because it just cannot be. “DHT receivers are perfect, the strongest receivers every made, ever will be made, etc, etc.” You see this in the referenced article.

Unfortunately, DHT receivers were made from the same erratic, shallow hardening plain carbon steels as the SHT.

As far as to sticking with plain carbon steels, someone at decision making high level at Springfield was against alloy steels. In the 1916 instructions to bidders for the 03 rifle, Springfield Armory specifically forbid the use of Nickel steels. This might have been the only alloy steel they were aware of. This sort of dogmatism is surprising to find in a bid package, especially as alloy steels are much better than plain carbon steels. Maybe the Chief Metallurgist, had something against alloy steels.

Making such a labor expensive complicated piece, such as a receiver from such an inferior material as plain carbon steels could be understood in a 1890’s historical context, but pre WW1, when Winchester was making rifles from nickel steel and the P1917 was made from nickel steel, it was time for an upgrade. Instead, SA practically doubles their process costs to add a salt bath for the second heat treat.

It took finishing the nickel steel RIA receivers and making receivers for a decade from unused RIA nickel steel stock before SA decided to advance in the 20th century. I figure that by the time they ran out of nickel steel stock the Chief Metallurgist had died.

Sometimes, mortality is the only means of progress.

For those proponents of SHT receivers, just keep shooting them until progress happens.
Last edited by Slamfire; 03-29-2010 at 09:11 AM.

[Cosine26]

Use of the Field Test Bolt to check Headspace
From Brophy's book

https://imgur.com/uCYXYE6

[Cosine26]

Hi pickax
An interesting article by “slamfire” that you sent.
The one I was interested in was published as:
LN Receiver Steel
08-07-2025, 06:47 #24

[pickax]

Hi pickax
An interesting article by “slamfire” that you sent.
The one I was interested in was published as:
LN Receiver Steel
08-07-2025, 06:47 #24

I searched the 3 biggest forums under the title you listed and found nothing. I suspect it was here on CSP, but may be a disconnect from the old Jouster.
Regardless, I've learned the alloy receivers were, and are superior to the carbon SHT and DHT. versions, and why so.
Also, digging through old threads reminded me of nuggets from the old salts I had forgotten through the last few years.
Time to read Major Culvers notes again too.
Thanks for the info to all you old salts, it is appreciated.

[Cosine26]

pickax
Try this ur
http://www.jouster2.com/forums/showt...hinking)/page7

[lyman]

pickax
Try this ur
http://www.jouster2.com/forums/showt...hinking)/page7

thank you for reposting that thread,

I've skimmed thru it and now need to go back and read every post,,

here is some more info,, recently come to light

https://forums.gunboards.com/showthr...n-from-service