No.4 mk1 bolt question

Some of the cases I was using were once fired in this rifle, the other half were unknown range pickup that chambered in the rifle. All the Winchester brass I fired either separated or showed signs of doing so, the one that came apart in the rifle was stuck hard. Rod and brush wouldn’t remove it, broken case extractor even had problems at the range.

Managed to get it out at home with the extractor but once I got it in the broken case the bolt and extractor claw couldn’t pull it out. I had to pry it out by the case extractor rim with two big flat head screwdrivers, one from the magwell and the second from the top of the action. Finally it popped free, glad I picked this up last year at the Kamloops show.

XfUuzUb.jpg

9n9BB6P.jpg
 
BLC, the forerunner of BLC2, was originally developed for the 303 British cartridge.

From what I've read, the "B" stands for British.

It was later used in other military cartridges as well.

Good choice.

Those shiny rings on the neck indicate there are other issues with that rifle.

What surprises me is the case head separation.

Normally, the brass would flow and just fireform to the chamber.
 
The shiny ring on the neck is from the broken case extractor, the ridge at the end of the expander of the collet made it as I tried to pound it out from the front end but that get it out, so I used the two flatheads to pry from the back. I’ll post some pics of the other brass that didn’t separate. Nothing else has a ring at the neck, if you look at the neck of the second broken case there’s no ring.

Nqpc5Dt.jpg


I’m not surprised that this brass separated, I picked up these 20 or so odd pieces at the range. Who knows how many times they’ve been fired, I checked them with a wire and they seemed fine. They chambered with a slight resistance but the bolt closed, it was only the Winchester cases that cracked and came apart. All the other 25 I loaded with 4320 were once fired in this rifle and had no seperation problems.
 
If that's s&b brass, that's not unusual. I use it twice and recycle. My lee speed clone has some excessive head space and it won't even do one firing.

Just read it winchester. I had some winchester that wouldn't hold neck tension either. Fine for my .314 cast bullets, but 311 jacketed I can pull out with my fingers.
 
Here’s pics of the separated case heads one was Winchester the other just says .303 British, no ring on the necks. You can see the ringed neck next to the broken case extractor, which is where that ring is from.

None of the other brass or the brass that is once fired has that neck ring.

2H8OSA7.jpg

8NwKiYM.jpg

HS5M0Yi.jpg


Once fired PPU from this no.4
m4JAT0y.jpg
 
Use the expander ball from your 30 caliber die instead and that problem will go away.

The first thing I do with Winchester, Federal, and S&B cases is anneal them unless they're new out of the bag.

I also anneal all range pick-up brass I bring home to use myself.
 
I've had issues with the (blue bag) Winchester brass in 303. Neck splits on second firing, with minimal resizing. Problem resolved by annealing. As I understand it, brass is annealed several times during the forming process. Perhaps Winchester cut some corners. The net result is thin brittle brass that cannot accommodate expansion during firing.
 
cosmic said:
I've had issues with the (blue bag) Winchester brass in 303. Neck splits on second firing, with minimal resizing. Problem resolved by annealing. As I understand it, brass is annealed several times during the forming process. Perhaps Winchester cut some corners. The net result is thin brittle brass that cannot accommodate expansion during firing.
Click to expand...

Some folks say it's due to the high Zinc content in some lots of Winchester brass.

I have a few hundred Winchester cases for 7x57 Mauser, which have at least twenty reloads on them.

I re-anneal them after the third reload/firing. A few have had to be tossed because of split necks, but most are still going strong.

Other companies have had similar issues with their cases, Federal, Remington, and Speer come to mind.

It all boils down to how much they're willing to spend on the materials and ease of manufacture.
 
I wonder, could it be that ammo makers are working on planned obsolescence, aka planned failure?

🤔
 
I think it just boils down to the cost of materials.

There gets to be a point when it's no longer financially viable to produce with the best proven materials.

So, the manufacturers substitute other materials to produce a usable but inferior product.

There was a time when all military cartridge cases were made of excellent quality brass. This was done for several reasons, mostly, it was easy to work with and easy on the firearms it was used in.

When material shortages became the norm, some nations switched to mild steel and because of the decreased cost of production, continue to use mild steel to this day.
 
You must log in or register to reply here.
Back
Top Bottom