My new rig.

[A Guy Out West]

I just acquired a new Winchester Model 70 Super Grade in .264 Win. Replaced trigger spring with an Earnie The Gunsmith spring, mounted a Sworo 3x10x40 Z 3, using Conetrol mounts. Targets are all 3 shot groups except the one on the lower left of the orange centered target, it is 4 shots. Gun seems to want to put the first two in the same hole or touching each other and then the 3rd be a flyer. I allowed the barrel to cool between shots but perhaps not enough??? Target on the left and the target on the right center are the same powder charge. Center target on right is 66.6 gr. Then each group was increased by 1/10 gr. Very surprised at how 1/10 of a grain can change the group. This was my second outing today, pleased so far. One speed bump I ran into. Since I couldn’t find any .264 brass I used 7 Rem brass. I ran it through the sizer die and squeezed the whole neck to .264 diameter. When I went to the range, I had several misfires. Because I had resized the full length of the neck, I had resized way too much, thus the misfires. When I reloaded that first batch of brass, I only resized about half way down the neck. The misfires went away. Wondering if I only resized the 7 mag brass half the length of the neck, if that will be ok. Seems like it should be ok. New to this belted cartridge reloading. In case your wondering, bullet is a 90 gr Speer TNT, powder was H 100 V Hybred.

 

[scotch_egg]

Wow, a 90 grain bullet and 66 grains of powder.

What will you be hunting with that combination?

 

[A Guy Out West]

California ground squirrels.

 

[NP435]

You are on track, belted cases don't have to head space on the belt just don't push the shoulder if you can rechamber fired brass before sizing you will know what you can do. I push shoulder'sthe least amount I can do and still close my actions.

 

[NP435]

California ground squirrels.

All of whom are named target?

 

[A Guy Out West]

Actually, they have a little sign that says shoot me.

 

[scrumbag]

Shoulds like one heck of an antelope rig.

 

[John Gryphon]

Guy,I`m jealous!

 

[borbal]

It is tempting to treat belted cases like rimless cases and allow them to blow out in the chamber, then effectively headspace off the shoulder - if you don't push the shoulder back when you resize the brass.

A word of warning though. What tends to happen then is that a small gap is left between the belt on the brass and the belt shoulder in the chamber. That leaves small length of the body of the case unsupported, just ahead of the belt. Now, the brass at that point is actually quite thin. You should section a case and see for yourself that the thick base of the case is all below that shoulder on the belt.

So, what happens as you repeatedly reload the case is that the pressure pushes out that little ring of brass just ahead of the belt, and eventually it lets go and you get a case head separation.

Guess how I found that out...?

The short version of this story is that belted cartridges are not really meant for reloading.

The thickness of the belt on the case is always made small by the manufacturer by a surprising margin to ensure that despite the manufactured tolerance variations in belt thickness, the brass the will always go into the chamber. So if you headspace the rifle using a standard headspace gauge (as you normally should) then you will always leave that small vulnerable gap just ahead of the belt when the cartridge is loaded into the chamber.

A way to get around that problem is to machine all the case belts down to a thickness where they all clean up to that thickness, then headspace the rifle to that belt thickness.

The moral of this story is that all reloaders should have a lathe...

 

[Klenchblaize]

Nice scope mounting system.

K

 

[A Guy Out West]

Shoulds like one heck of an antelope rig.

Actually, That’s what it’s for. Hope to use it this September.

 

[A Guy Out West]

Guy,I`m jealous!

Your welcome to come shoot it anytime.

 

[zambezi]

The moral of this story is that all reloaders should have a lathe...

Could I please have that in writing on a page with an authoratitive letterhead?

It's just that my petitions to the comptroller have not been successful thus far.

 

[takbok]

Lovely rifle @A Guy Out West

 

[Utectok]

Btw a lot of people complain of two touching holes and one further away... my understanding is that is maths and probabilities not the rifle.

 

[John Gryphon]

Your welcome to come shoot it anytime.

Thank you,i have wanted a 264WM forever it seems Guy.

 

[Namman]

It is tempting to treat belted cases like rimless cases and allow them to blow out in the chamber, then effectively headspace off the shoulder - if you don't push the shoulder back when you resize the brass.

A word of warning though. What tends to happen then is that a small gap is left between the belt on the brass and the belt shoulder in the chamber. That leaves small length of the body of the case unsupported, just ahead of the belt. Now, the brass at that point is actually quite thin. You should section a case and see for yourself that the thick base of the case is all below that shoulder on the belt.

So, what happens as you repeatedly reload the case is that the pressure pushes out that little ring of brass just ahead of the belt, and eventually it lets go and you get a case head separation.

Guess how I found that out...?

The short version of this story is that belted cartridges are not really meant for reloading.

The thickness of the belt on the case is always made small by the manufacturer by a surprising margin to ensure that despite the manufactured tolerance variations in belt thickness, the brass the will always go into the chamber. So if you headspace the rifle using a standard headspace gauge (as you normally should) then you will always leave that small vulnerable gap just ahead of the belt when the cartridge is loaded into the chamber.

A way to get around that problem is to machine all the case belts down to a thickness where they all clean up to that thickness, then headspace the rifle to that belt thickness.

The moral of this story is that all reloaders should have a lathe...

???