Barrel blank size for Bat M?

[robbor]

What size blanks are you running at the shoulder for a bat M multiflat 1.47" action.

I believe 1.25" is bare min.
I was thinking closer to 1.35"
Suggestions????

 

[LVLAaron]

1.25 min

 

[quest450]

1.450" chubsy ubsy

 

[quest450]

 

[Walt Krafft]

1.25 works fine. Going bigger costs quit a bit. What problem are you trying to solve?

 

[FrankG]

The BAT M's have 1.125" breech diameter threads. If you go with a 1.250" barrel diameter that only gives you about .062" a side for the shoulder to butt up against the receiver face. It's doable but your pushing it.

The other question that you have to ask is what are you chambering it in? If something like a 338 Lapua type round... you will want a 1.350" breech diameter. That extra meat in the chamber area for the diameter helps with barrel expansion and fired case extraction. Also gives you more shoulder contact for the barrel against the receiver face.

 

[jackieschmidt]

I shoot regular Heavy Varmint profiles, which are 1.250 nominal diameter at the breech end, on my BAT M action with no problems.

However, it certainly does not hurt follow the advice offered by FrankG.

 

[Ryan M.]

1.250

 

[FrankG]

I shoot regular Heavy Varmint profiles, which are 1.250 nominal diameter at the breech end, on my BAT M action with no problems.

However, it certainly does not hurt follow the advice offered by FrankG.

Jackie also brings up a good point that I forgot to mention. In Jackies case unless I'm mistaken... he is running a HV profile barrel. The other thing to think about on F OPEN guns a lot of shooters are running straight no taper barrels. So they tend to weigh more. A 1.250" diameter straight blank at 32" is going to way about 10.5 pounds vs a HV with a .900" muzzle at 28" which only weighs about 7.5# or a smidge less.

All of that extra weight... having a bigger shoulder spreads the load out more against the receiver face.

I think there is something to a rail gun or even a rail gun set up in a conventional stock I've seen on F Class guns where they barrel clamp the block to the barrel.... your freeing up all that hanging weight on the action so the action just floats in the stock etc... your taking all that strain off the receiver face from the barrel weight.

Just food for thought.

 

[falconpilot]

I've run long, straight 1.250 on my BAT M for years and never had an issue...had lots of great shooting guns, that set a few records...I'm sure there is merit is what Frank is saying, but I personally haven't found it to be a problem. I've been shooting BAT M's since I started F-Class in 2008..

 

[4xforfun]

I have 3 "M" actions. I run everything from a 6 Dasher all the way up to 338 EDGE in mine. All tubes except one are 17# HV........1.25 @ breach for 5 " down to .9ish at muzzle. The other is a 6 dasher on a Heavy Palma.....1.2 for a couple down to .9ish.

I never felt un-safe or the need to hide my face with the big guns with a 1.25 tube on a 1.125 tennon.

Just my .02

Tod

 

[Mark Buettgen]

It's not about the minimum or what could work, a better question to ask is, what is better or best.
If you can get more shoulder contact on the receiver, you are better off. Cantilevering 10.5 pounds on .060" or .112"---I'll go with more shoulder contact on mine.
Later, Mark

 

[LVLAaron]

... I've thought about threading, gluing, and polishing in a collar for my M barrels....