.264 Win Mag headspace

[solocam]

What’s considered safe headspace in a belted cartridge like .264WM? I’m pretty sure the one I have is unsafe when I compare it to my .300WM.

 

[Steel head]

You talking about new brass growth upon firing?

 

[solocam]

You talking about new brass growth upon firing?

Yes. I’m getting.038 growth. Seems excessive to me.

 

[solocam]

Okay, I know belted magnums headspace off the belt.....so calling it head space is the wrong terminology. Case growth seems to be the correct lingo. My .300EM case only grows .013”.

 

[mudpig]

Seems bad, but as long as you're not repeatedly pushing the shoulder back to like new dimensions, you should be just fine. When fire forming some wildcats, I pushed the should forward .200+ and all is good. From your fired case only push the shoulder back about .002 and all will be good to go.

 

[solocam]

Seems bad, but as long as you're not repeatedly pushing the shoulder back to like new dimensions, you should be just fine. When fire forming some wildcats, I pushed the should forward .200+ and all is good. From your fired case only push the shoulder back about .002 and all will be good to go.

Thank You

 

[Steel head]

Yes. I’m getting.038 growth. Seems excessive to me.

Almost 40 thou?

unlesss your creating a false shoulder or jamming the bullet hard on first firing that’s enough that I’d be worried about case separations

 

[Yote Klr]

.015" is about normal on most belted magnum cartridges.

 

[supercorndogs]

.015" is about normal on most belted magnum cartridges.

This is about what I have seen in a couple of 300wm chambers. Three times that seems excessive.

 

[Yote Klr]

But just think, you'll have a lot more case capacity after fireforming! Just make sure you only bump the shoulders .002 or .003".

 

[solocam]

Almost 40 thou?

unlesss your creating a false shoulder or jamming the bullet hard on first firing that’s enough that I’d be worried about case separations

Thats exactly what my concern is about. This is factory ammo stretching that much.

 

[Yote Klr]

How exactly are you measuring this?

 

[supercorndogs]

I bet the brass is already stretched thin at the web. I would inspect them carefully for signs of CHS.

What rifle is it?

 

[solocam]

Using Hornady’s headspace comparator (E420 bushing). Rifle is an older Winchester Model 70. My dad bought it used back in the 80’s. I have no history of the rifle. It wouldn’t extract shot cartridges when I got it. Replaced the bolt extractor with a new one, it extracts shot brass fine now. After looking into the rifle more I discovered the case stretch issue. Ammo is factory Nosler 130g AccuBond.

 

[Steel head]

Using Hornady’s headspace comparator (E420 bushing). Rifle is an older Winchester Model 70. Ammo is Nosler 130g AccuBond.

If the lugs look ok a bit of work on the barrel should be a easy fix.
I personally wouldn’t run it like that.

 

[supercorndogs]

Do you get any pressure signs? Have you checked it with a headspace gauge?

 

[solocam]

Do you get any pressure signs? Have you checked it with a headspace gauge?

Brass not showing anything. I haven’t checked with a headspace gauge.

 

[supercorndogs]

I would want to put a headspace gauge in it before shooting it anymore. If the belt headspace is ok it would seem like its probably always been that way, and there are probably many more like it. I wouldn't want to reload that factory brass. You could fire-form to reload for it.

 

[Steel head]

You could fire-form to reload for it.

This!
264 Winchester improved!

 

[solocam]

Not really looking for extra case capacity. .264WM has plenty of capacity with today’s powder in a .264 projectile. I’m just concerned if it’s safe. How much do you guys think it would cost to set the barrel back a bit? I would like to reload for it. I already have reloading dies for it, otherwise I’d rebarrel it to something with cheaper more available ammo.

 

[Steel head]

Not really looking for extra case capacity. .264WM has plenty of capacity with today’s powder in a .264 projectile. I’m just concerned if it’s safe. How much do you guys think it would cost to set the barrel back a bit? I would like to reload for it.

Buy new brass
Create false shoulder for first firing.
That will minimize case stretch of side wall.

I’d call LRI or another well known smith.

 

[Yote Klr]

That's tough, being it's your dad's rifle.

If you did have it set back at least you'll have actual use with your dads gun.