.303 cartridges MK Vll

[brassrat]

These are nice, paper wrapped,10 rds. How scarce and worth?

[Dutchman]

Insufficient information.

Photo helpful.

Dutch

[Multigunner]

Most older MkVII ammunition is only good for components.
It depends entirely on age and how well the ammo was stored.

Some like to claim that hangfires are not dangerous but I've seen photos of the result of someone mistaking a hangfire for a misfire, it wasn't pretty.

Some old milsurp .303 ammo was remanufactured with fresh primers and the cordite inspected with degraded strands discarded before reloading. Only heard of this being done in Australia. This remanufactured ammo would likely be better than its age would suggest, but I doubt any of it is still available.
A bit of the older MkVI ammo was remanufactured in this manner back in the 70's, for target use with the old LE rifles, the same source advertised Krag ammo remanufactured in much the same way.

Kynoch MkVII surplus ammo has been offered in recent years, and seems to have been stored under optimum conditions.
Kynamco, the sucessor to Kynoch produced some freshly made MkVIIz ammo using surplus Radway Green MkVII projectiles, but they ran out of these NOS bullets long ago and now use the SMK boat tail bullet.
No one makes Cordite for rifle ammo these days.

[Larry Gibson]

South African 303 ammo made at the Pretoria West Metal plant/arsenal/ammunition manufacture(?) is excellent ammunition. It is very accurate in my Ross Mk 10 and runs 2472 fps. It has 39 gr of extruded powder in excellent brass cases with non-corrosive Berdan primers. The stuff I picked up (300 rounds) was made in 9/80. As stated the cases are of excellent quality and well worth the small effort to convert to boxer primers. I've converted 20 cases (left one) and they have been reloaded 7 times. Besides the original firing one was with a top end load of 4895 under a Hornady 150 gr SP. Not a single problem with any of them.

Larry Gibson

9468894689

[karlrudin]

I dont have any experience with 303 britt vintage ammo, but have a lot of 8mm mauser that dates to the early 1930's. What I do is break them down with a kinetic puller, dump the powder, check the inside of the case for corrosion and reload with modern powder. My reason for this is with my light self, 135lbs, I can't take the hit from this heavy ball ammo. So I tone it down a bit, reload and wham. I always clean weapons after shooting, so the corrosive primers don't cause me any grief. Haven't had any problems yet with any of them not going off.

[Multigunner]

I have some 80's vintage HXP .303 ammo, its solid lead core not the MkVII projectile.
Boxer primed brass case with powder.
If the bullet does not have the light weight nose plug its not really a MkVII bullet.

MkVII ammo is the MkVII bullet over Cordite. If powder is used rather than Cordite it would be MkVIIz ammunition.

[cpileri]

I always wanted to try these projectiles out of 7.62x39 or similar .311 chambering. Heavy for caliber, but still...

Anyway, i have some cut away pics on this thread;


http://castboolits.gunloads.com/showthread.php?227779-Cool-303-british-ammo-w-pics!

C-

[brassrat]

It is said everyone likes pics so...


http://i1123.photobucket.com/albums/l542/g5uis23ft5h/th_IMG_0008_zpsc0b24c1e.jpg (http://s1123.photobucket.com/user/g5uis23ft5h/media/IMG_0008_zpsc0b24c1e.jpg.html)

[Multigunner]

Remember if using the MkVII bullet to reload, the MkVII at 172-174 gr FMJ has the bearing surface of a 225 gr all lead core FMJ spitzer. A significant increase in engraving resistence and bore friction compared to more common 175-180 gr all lead core jacketed bullets.
This might cause excessive pressure if the same powder charge were used as you'd have used with the common sporting bullet in that weight range.

I had a flattened cratered primer and swollen pocket when I used a salvaged MkVII bullet over a near max charge of IMR 4064 that I'd used with the 180 Speer bullet with no pressure signs.

[gew98]

Remember if using the MkVII bullet to reload, the MkVII at 172-174 gr FMJ has the bearing surface of a 225 gr all lead core FMJ spitzer. A significant increase in engraving resistence and bore friction compared to more common 175-180 gr all lead core jacketed bullets.
This might cause excessive pressure if the same powder charge were used as you'd have used with the common sporting bullet in that weight range.

I had a flattened cratered primer and swollen pocket when I used a salvaged MkVII bullet over a near max charge of IMR 4064 that I'd used with the 180 Speer bullet with no pressure signs.

Did you check diameter of both said bullets in comparison...did you also note the Speer have a softer alloy jacket too ?. I've never run into this problem with 303 , 7.92 , 6.5 , 5.56 etc etc.... as checking commercial bullet diameters relevant to issue FMJ's and actual bores makes a wee bit of difference.Just a little ... but hell what do I know.

[Multigunner]

Both were for the .303, the MkVII was a POF.
If the load had not been near max there would probably have been no pressure sign with the MkVII.
The bore of the rifle has a .314 major, so tight bullet to bore fit was not a factor.
Only reason I used such a hot charge with the Speer bullet was because the accuracy was better at near max loads.
Since going to the Hornady .312 bullet hot charges are not necessary. The Hornady bumps up more easily.



I've never run into this problem with 303 , 7.92 , 6.5 , 5.56 etc etc
Since the MkVII bullet is only made in .303 the results with 7.92-6.5-5.56 etc etc are irrelevant.

Whenever substituting any component its best to back off from the previous powder charge and work back up by half grain increments. That's something I should have remembered, and will certainly remember in the future.

The only comparable bullet I can think of offhand is the WW2 Italian 7.35 some of which used a similar lightweight nose plug of aluminum alloy. I don't think many of those were produced.

When the total weight of the core is reduced in comparasion to a solid lead core bullet the over all length of the bullet will be greater for the same weight of bullet. If theres no boat tail or other factor to reduce bearing surface the bearing surface of the bullet with composite core will be greater than that of the more conventional bullet of the same weight.
The MkVII has a noticeably greater bearing surface than other bullets in its caliber and weight range. The profile is based on the 225 gr "Swift" long range target bullet. This longer bearing surface contributes to accuracy in the commonly oversized .303 bore and helps compensate for erosion of the leade.

[taco650]

South African 303 ammo made at the Pretoria West Metal plant/arsenal/ammunition manufacture(?) is excellent ammunition. It is very accurate in my Ross Mk 10 and runs 2472 fps. It has 39 gr of extruded powder in excellent brass cases with non-corrosive Berdan primers. The stuff I picked up (300 rounds) was made in 9/80. As stated the cases are of excellent quality and well worth the small effort to convert to boxer primers. I've converted 20 cases (left one) and they have been reloaded 7 times. Besides the original firing one was with a top end load of 4895 under a Hornady 150 gr SP. Not a single problem with any of them.

Larry Gibson

9468894689

Larry,

How did you do the conversion to boxer priming?

Stuart

[Larry Gibson]

Larry,

How did you do the conversion to boxer priming?

Stuart

Fully explained in; http://castboolits.gunloads.com/showthread.php?143958-Converting-Berdan-primer-pockets-to-Boxer

If you've any questions don't hesitate to ask. It is really quite easy to do.

Larry Gibson

[taco650]

Fully explained in; http://castboolits.gunloads.com/showthread.php?143958-Converting-Berdan-primer-pockets-to-Boxer

If you've any questions don't hesitate to ask. It is really quite easy to do.

Larry Gibson

Nice write up (as always with Larry ;-) ).

Only problem is I needed to have read this 30 years ago when milsurp loads were available for the 303 British. My dad bought a couple boxes for his #4 Mk 1 and they had really good brass. I tried messing with them back then looking to convert to boxer but had no luck. Ended up tossing the whole lot after they were fired. Now I can't find regular 303 brass to load, guess I'll just have to buy loaded ammo and shoot it to get the brass. At least they'll be fire-formed to my chamber.

[Larry Gibson]

After I figured out how to do the conversion I thought about all the good brass cases I've tossed over the years.......was enough to make a grown man cry.........:sad:

Larry Gibson

[brassrat]

Any info on these cartridges?