This BAT SV action

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Ben Hooper
Got my shiny new SV action. Have a couple questions if anyone here is familiar with this particular action.

The machined area on the action bottom acts as a recoil lug? I assume you fill it with bedding compound when bedding?

What do I use for a data point when machining the barrel cone?

I was planning on using a depth mic to the bolt face, and work back from it?

What a beautiful piece of machine work this action is!

Ben
 
Ben

I have had a couple of SV's, nice little action.

The machined area on the bottom is probably to shed weight, but will act as a recoil lig when bedded. But the glue in is really what keeps things intact.

If it is not a glue in, then I suppose that small register in the front of the cut away will help and act as a recoil lug. But, that edge is at a angle, not condusive to absorbing recoil.

I bed the entire action when I do a glue in. Do the same with a bolt in.

As for the cone, I establish all of that when I get a new action. I made a little gage that allows me to duplicate a cone's dimensions, once I come up with a figure. As crude as it sounds, I just use trial and error on that first one.. Remember, that action has a 25 degree cone.

If I do a barrel for an action that is used, I will screw a barrel into it and get a base line.

I have a fired case that I always stick into the chamber after I finish the cone so I can have a visual check as to exactly where things are. Remember, the main thing is to not cut the cone too deep so that the solid part of the case web is exposed. On cases such as the PPC and BR, this is pretty criticle.

If you stick a case into the bolt face, you will see exactly where the forward end of the extractor groove is in relation to the edge of the cone. An actions such as Farleys, he gives you very little to play with, on actions such as Vipers, there is considerably more. Bats are sort of in between.........jackie
 
For the custom actions with a cone bolt, I treat each one as an individual. I make a barrel stub just to have one for comparison in the future and for practice.
First, thread the stub and set the barrel end to shoulder in the normal manner. Then I set the compound on the correct angle and take a reasonable amount off of the cone in the barrel. When doing this, I have a dial indicator set to know where the carriage is during this cut. A micrometer carriage stop would work fine, also.
I then screw on the receiver with the bolt in place and closed. It will not go all the way on and there will be a gap between the receiver front and barrel shoulder. Get this dimension with a caliper or feeler gages and then make another cut using the dial indicator as a guide to the amount of material taken off. When I have something like .005 or ..020, I'll simply take off that amount plus .005 more.
With the action installed, you should be able to feel a small amount of fore and aft movement with the bolt handle when the bolt is closed.
This goes pretty quick and works for me.

Jackies idea of putting a case in the finished chamber is a good idea even on the non-cone bolt barrels, I think.

Jay, Idaho
 
I have four SV's. Have a new one coming in ChromeMoly. The cutout is to act as a recoil lug on small cartriages. I have one pillar bedded in a stock with no recoil lug, just the cutout and the rear of the tang fitted. Gun has always shot excellant and has well over 3000 rnds on it and no problems have arose. I don't think I would use it for anything bigger than a ppc like that though.

Hovis
 
One of my BAT 3Ls was purchased without the integral recoil lug, and it has the same machined flat on the bottom of the action as your SV. I've asked about it, and been told by a friend in Phoenix whose opinion I trust that there are several HP shooters out there using the 3L w/o lug with cartridges as large as a straight 284 - shooting 180gr. bullets - with no problems. Of course, this would be good incentive for using a tough bedding compound like steel filled Devcon, and making sure the tang is also solidly bedded. My action is set up with a barrel chambered for the Dasher, so I'm not real concerned about it. My other three BAT 3Ls all have the integral lug.

If it's a problem, you could always use a Holland lug, but the flat at 6:00 on my 3L actions doesn't leave a lot of room for a pin.

I fit coned barrels using the same method Jay described, and cut the cone angle 1* to 1-1/2* wider than the bolt - eg - 26* - 26.5*. I don't want something as small as the bristle off a bronze bore brush getting caught between the bolt nose & breech and tying the action up during a prone match, so I try to leave .005" clearance by cutting the cone .007" deeper than the measured shoulder/action gap to allow for .002" crush. Perhaps I need do only one or the other - wider angle or deeper cone - and not both to get the clearance I'm after?
 
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Keep in mind on a square tanged action like the BAT, that tang acts as the primary recoil lug when bedded properly.
 
jackie schmidt said:
As for the cone, I establish all of that when I get a new action. I made a little gage that allows me to duplicate a cone's dimensions, once I come up with a figure. As crude as it sounds, I just use trial and error on that first one.. Remember, that action has a 25 degree cone.
Click to expand...

Sounds ok to me, it was my plan too!

I was hoping the action would come with a drawing and basic instructions.
 
jackie schmidt said:
As for the cone, I establish all of that when I get a new action. I made a little gage that allows me to duplicate a cone's dimensions, once I come up with a figure. As crude as it sounds, I just use trial and error on that first one.. Remember, that action has a 25 degree cone.
Click to expand...

Sounds ok to me, it was my plan too!

I was hoping the action would come with a drawing and basic instructions.

Thanks

Ben
 
This Bat SV action

Quote: "I was hoping the action would come with a drawing and basic instructions."

When I got my BAT SV I emailed BAT and asked for a drawing. They sent me one with a cautionary note to the effect that they made many slightly different actions so the drawing may not be correct for my action. It serves as a starting point.

Scott Roeder
 
SGS said:
Quote: "I was hoping the action would come with a drawing and basic instructions."

When I got my BAT SV I emailed BAT and asked for a drawing. They sent me one with a cautionary note to the effect that they made many slightly different actions so the drawing may not be correct for my action. It serves as a starting point.

Scott Roeder
Click to expand...

Thanks. email is away.
 
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