Thread: Headstamp on 303 reloads

My neighbour just bought a 303 as his first rifle and was trying to sight in at the weekend, along with his ever so know-it-all mate.
I popped up to see how it was going to find he had gone through a whole box of 180 Winchester and was still not able to hit a 6 inch gong at 100 yds. (it was actually only 84 yds when I ranged it )
His mate dug a few re-loads out of his pocket and told him to use them. The first two failed to fire, despite primer being well and truly pricked. The third shot went off.
It was only while he was getting sorted for the third shot that I picked up one of the mis fires, and noticed that the head stamp didn't mention 303 .
It simply had cac 7 stamp on it, as did the other reloads. I tried to suggest that it was possibly dodgy amo, but his mate insisted that he had used at least 30 of the same without issue.

My knowledge on this is next to nothing, but it didn't seem right to me. Was I right to be concerned ?

@Pengy
My advise to your neighbour, or anyone for that matter, is don't swap reloads between rifles.
The rounds you have identified would appear to be Mk 7 (the last of the series numbers used for 303 military ammo) and as such are Berdan primed. Only enthusiastic reloaders reload non Boxer primed brass. Is it possible they were "tired" factory ammo? I think the last run of CAC Mk 7 was around 1958.

To save further ammo he needs to fire at a target a hellava lot closer. Might pay to first drop a loaded round down the muzzle and see how far the projectile goes into the barrel. Mate's father's one, that hung on the back of the wash house door at the farm, and was used to shoot deer a fabulus ranges, would accept the catridge projectile and all right up to the brass. We had trouble hitting a 25yd target and all shots keyholed.

Yea I have some 303 brass with no caliber stamp on the end....Im not clued up on the origin of it

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The guy with the reloads said a mate of his loaded them

mmmm CAC did also produce commercial 303 ammo. I cannot remember what head stamp though, and it probably was easily reloadable ie Boxer.
Despite the good primer indent the headspace could still be way out and a lot of the firing pin force is wasted pushing the cartridge forward into the chamber.

Best to stand out to one side whilst they are shooting

Originally Posted by zimmer

mmmm CAC did also produce commercial 303 ammo. I cannot remember what head stamp though, and it probably was easily reloadable ie Boxer.
Despite the good primer indent the headspace could still be way out and a lot of the firing pin force is wasted pushing the cartridge forward into the chamber.

Best to stand out to one side whilst they are shooting

I made sure I was well away from him mate
Thought it may be a head space issue, but was more concerned the amo was not correct for cal

Something to consider is that 4moa was considered up to scratch when the rifle was made, use/cleaning/sportarising all could have degraded that number even more.

I second the call to start closer, and get some known factory ammo

Originally Posted by zimmer

To save further ammo he needs to fire at a target a hellava lot closer. Might pay to first drop a loaded round down the muzzle and see how far the projectile goes into the barrel. Mate's father's one, that hung on the back of the wash house door at the farm, and was used to shoot deer a fabulus ranges, would accept the catridge projectile and all right up to the brass. We had trouble hitting a 25yd target and all shots keyholed.

This. Hit basic stuff closer, then stretch the legs 2nd. Waaay cheaper on ammo :-)

Try and avoid boat tail bullets if you can, even buggered barrels will shoot flat base ok, but keyhole the other type

Originally Posted by Pengy

..
Thought it may be a head space issue,..

.303Br headspaces off the rim and unless the bolt head has been interchanged, it should be fine.

As Zimmer suggested, the brass is ancient and probably brittle as hell. I'd suggest your "mate's mate" gets some modern S&B brass (and some good advice) and goes from there

Originally Posted by 6x47

.303Br headspaces off the rim and unless the bolt head has been interchanged, it should be fine.

As Zimmer suggested, the brass is ancient and probably brittle as hell. I'd suggest your "mate's mate" gets some modern S&B brass (and some good advice) and goes from there

@6x47 yep correct about the headspace - wasn't thinking clearly was I?

Originally Posted by 6x47

.303Br headspaces off the rim and unless the bolt head has been interchanged, it should be fine.

As Zimmer suggested, the brass is ancient and probably brittle as hell. I'd suggest your "mate's mate" gets some modern S&B brass (and some good advice) and goes from there

I wont pretend to understand the head space thing to be honest, but had heard of issues in the past, so thought it my be connected.
Unfortunately, `mate`s mate` is the worlds expert on everything, so wont listen to any one else.
Fortunately, the owner of the rifle is a little more open minded. I will quietly suggest he gives the reloads a wide berth

This is what I have left, the silver primer is a round nose projectile, the other CAC is run of the mill military stuff, they do measure slightly differently with the calipers than the Whinchester. PPU might also be worth trying

Get VC to shoot it. I have seen him hit a steel plate twice at 485 yards with an open sighted 303, the second time was when I bet him he could not do it again after the first hit

also worth trying different weight factory rounds some prefer 150s and others the 180s.....stuff using unknown dodgy reloads,I like my own teeth just the way they are.