BAT action softer steel?

Maybe to prevent galling..
Anyway, they don't wearout any quicker than aluminum actons, so I expect ~10,000yrs out of mine.
 
never fear

I dont know the metalurgical names for the metal in Bat actions/bolts ...but never fear ,,,it had been well thought out and us shooters just have to worry about the wind....and OBTW,,,there is a large mis-conception abut aluminum actions (Stolle/Stiller) ....they have steel inserts in the action where the bbl threads and bolt lugs engage...so it is steel to steel where the wear takes place....the aluminum is used in the body of the action to reduce weight ,dampen harmonics ,and disperse heat away from the chamber/bbl tennon...Roger
 
Hardness

The material used (17-4PH) is a precipitation hardening stainless material. It does not get quenched in oil to harden it. It is simply held at a temperature around 900 degrees for one hour. This material can reach a peak hardness of 42-44C. The level of hardness they are using is a little lower, but still considerable harder than a lot of mass produced stainless actions made from 416, which I don't even recommend for a quality action at all. The reason for the slightly lower hardness level is to make it more machineable. Heat treating after machining can be done, but the metal can move during the heat treat process causing the need for sloppy tolerances. Their material use an process is first class.

Michael
 
I am just worried about the nice shiny polished action surface gets scratched easily.
 
Bryan

Just to echo what others have said, that hardness level for the action body is just right, in fact, it is the same as most others use, probably age hardnenned at 1050 degrees.
The bolt is just about right as well, a good combination of hardness, tensil, yeild, and ductility.
This is the correct way to do things.
There are some different ideas among other manufacturers. For instance, McMillan for years have used a "case hardenning" for their bolts. That leaves the innner material at a softer RC number for maximum ductility, but the case hardenning, which is, I think, about .025 deep, is very hard, in the 50+ RC range.
The principle of dis-similiar metals at a different hardness is a time proven method when it comes to inducing anti-gall properties in two high strength parts that work together........jackie
 
mturner

Why do you think 416 cant be used for a high end action. Versus 17-4 it has sufficient toughness, typically used in the 40 Rc condition and has about 10% the chance of galling that 17-4 PH does. If the 17-4 wouldnt gall so easily against almost any other type of steel including 4140 and other alloys, that would make it a better choice, but the low sulfur high quality versions of 416 and 416R make just as good an action as 17-4, or 15-5 for that matter. I used to use 17-4 for all the steel inserts and main bodies. I got tired of the galling issues, went to 416 and never looked back. The only advantage of the 17-4 is the ease of hardening and somewhat higher toughness that is not required.

I have seen at least 3 bolts in the last few months that galled on the round part of the bolt just ahead of the handle due to a tight fit into a 17-4 action. Each one of the guys asked me my opinion if it was still ok to shoot. It was obviously still ok to shoot, but had to be sanded off on the bolt and inside the action to keep from getting worse. ANY piece of grit etc gets into that tight spot and it is galled. Between the 17-4 and the bolt fit being so damn tight (less than .001 is just not needed and probably detrimental) it is just an invitation to gall.
 
416

Some of the things I don't like about 416 are that it is a straight chromium grade of stainless that doesn't offer much in corrosion resistance. The other is that most production actions are softer in 416 than in 4140. Most won't make the 40C number. Maybe there are some special heat treating methods (like carburizing) that will offer greater hardness than the heat treat books list as the peak hardness levels of usually around 32C, but 17-4 is much easier to heat treat, warps less, and has a greater saftey in heat treat do to low thermal shock. Now I'm not saying 416 isn't a decent material with the best heat treating tricks out there, but it's not for me, and the processes I use in manufacturing. I generally stay with materials that don't require any more quenching than air. Remember that I'm not into volume production of actions. If the materials I use don't machine freely, I don't care. But I would like to add that I think you make a damn fine action. This is likely do to you refining your heat treat methods and following good machining practices. As for corrosion resistance, you don't really need it for an insert in a 7075 receiver. I witnessed your product early on when Jerry Hensler brought your action to the matches.

Michael
 
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