What a nasty surprise. I pulled the barrel (270) off a 1909 Arg action, planning to grind down the charger hump, reshape the rear tang a little, and reblue it. This is the action I just got the PME 2 pos safety set up on, new Leupold bases / rings, stock in the works, etc.

Looking it over, I thought 'my, that upper lug recess looks funny' -- actually it looks like the Steyr that Jack has posted pics of. I grabbed a small punch, and sure enough you can feel a step off when you run it over the front of the lug recess.

I will try to post pics if I can borrow a digital cam; the real bummer is, this was a DWM, in almost perfect shape, never fired with hot loads, barrel installed properly by a smith who knows how. I can't figure out why it happened.

Now I guess I'll be shopping for another good old 22 or 24.

Todd

Hey Todd, if you want to sell it email me offline.

Todd--

you might check with Blanchard about re- pack hardening it after re-facing the recesses. I'm not sure what their charge (or policy) is on receivers now. I think D'Arcy uses them and I know Ted Blackburn does.

Set the barrel back a turn, or less if you can get away with it.

This seems to be a little more common on the 1909 and the 1908 DWMs than one would like. I recently had what had been a new 1908 in the shop and it was also showing signs of setback.
I used a lot of unfired '08s in years past and most were just fine but occasionally one would be soft. The 1935 Oberndorfs we got at the same time were never soft and were definitely the better of the two. Regards, Bill.

For Todd, Jack, et all ref lug seat pocketing in
various mausers. The DWM '09's; After rockwell, DIN,and other hardness testing of between 450 and 500of these animals (category-09's)which included
cadaver research, (of some few that were beyond salvage), disecting and acid etch to determine carburising depth, I came to the conclusion that without exception they would all need additional depth of "case". Where it counts the depth rarely exceeds .007". Hardness? average about Rc 9.
Some were in the minus numbers, and rarely- perhaps 2 or 3 made it all the way up to Rockwell C 18.
The Argentines wanted to shoot up several 10's of millions of rounds of ammo made for the '91. The
bottom liners at DWM (Loewe) saved Marks by cooking the receivers and bolts in 10-12 minutes
less time. All that was determined to be needed for the '09 and the '91 ammo. Austria provided spitzer ammo about 200 FPS faster for the Schwarselose Machine gun, Troops and Jr ballons being the same the world over this ammo naturally got fired in the '09 rifles and carbines with a similar result to Todd's and a large ammount of them in original grease ended up on our shores 50 years later. I don't know about Ted but D'Arcy has been sending them same place I did for gas carburising. Old style pack hardening hardened in the same way as Gas. The heat liberated carbon monoixide which was absorbed by the steel. The gas
process is simply put a carbon monoxide atmosphere. Blanchard was using a cyanide salt process when I sent mine there. This is different in that it usually also induces nitrates & 'ides into the steel and tends to be self limiting as to depth plus it throws up boundaries in the higher manganese steels normal to the Mauser. I prefer a graduated transition into the core metal.
Remember that you are not dealing with a static load during the "instant" of firing. It is, rather
DYNAMIC- very much so with U.S. style propellants
as opposed to the early 1900's flake powders of the Germans. The .270 Todd can have as many as many as 5 "benches" in the so called pressure curve starting at about 93K PSI levelling of in the low 40's yet read a uniform load to load 58K in the old copper crusher method of pressure testing. An experienced pressure tester can almost tell you neck size, bullet free passage throat leade angle and other data by merely looking at the electronic test info on the scope screen with the loads used being referenced to his data file and a test standard barrel used to make his standards. I know ,More than you ever wanted to know. Get it fixed per Jacks prescription. Good Luck!

Lets say I have an 09' with no setback. Would it then be advisable to have it done to prevent future problems? Who could I contact to have this done? Does anyone have any numbers or addresses?

Told you about those Mausers. If you must have one look for a JC Higgins M50 or M51. They go for $250 or so complete and came in .270 and 30/06.

Work the bolt, shoot it and put it back in the safe.

I would like to see a complete cost analysis of the work needed to make a "Mauser" close to a M-70 and then it will never be close as they are soft!

Gentlemen,

I know his is getting slightly off the subject but it is related. If the bolt too were heat treated how would one accomplish the the task of getting the cocking cam and extractor cams hardened to a higher RC than the rest of the bolt? I ask because JBelk posted a fine description of how to harden these surfaces a while back and I believe he quoted numbers in the low to mid 50's. Blanchards says they shoot for 40-45. This seems to leave the camming surfaces a little softer than what Mr Belk recommended.

I ask because if the receivers were treated so quickly wouldn't the bolts likely have been treated similarly? Although harder than the receiver initially they might be softer than the receiver after it is retreated.

-M

[ 11-04-2002, 09:35: Message edited by: z1r ]

Thank you all for the information provided. Interestingly, I just picked up a couple (more) 1908 actions -- I guess I will adjust plans accordingly to stick to low pressure cartridges.

One more question -- since the gun doesn't show signs of 'dishing' in the lug recesses when you work the bolt (still lifts easily after firing), would it make any sense to just have it pack hardened and then re-headspace the barrel?

And some further info -- I had time for a little better look, and also dug out my mini-maglite for better lighting -- the setback is more prominent in the upper lug recesss, and I did NOT lap the lugs on the this action like I have been doing with the alloy Mausers, as I knew it was case-hardened. The bolt is not matching. I wonder if the setback would have occurred had the lugs been bearing evenly.

BTW, nice to see that we've added another well-known and respected gunsmith to the AR community. Welcome Mr. Burgess. And thanks again to Jack Belk, I knew I could count on you for some good input.

Todd

Get a VZ-24 and you won't have to worry about it.