30-50bmg

[dave338]

[this is for fun not practicality]
just looking at my cartridge shelf in front of me , and started to look at the 50 and the 308, now i know simply necking the bmg to 30 is just about pointless , but what about cutting the bmg case to about the same length as the .308,
would that not be a starting point for a short fat magnum ?
looked at the pac nor site and they have a 6.5-50 listed,
also 50-20mm pac-nor ackley improved googled it not much there
no sizes for these two ,
but what do you think , could it be the ultimate 30 short mag
or in fact 375 or 408 ?

 

[Winchester 69]

Re: 30-50bmg

Should be a snap with your new press. A forming & trim die should make it easy. You can turn the necks on your machine lathe. What action are you considering?

 

[slayer_21420]

Re: 30-50bmg

should be fun to play with, also look into the 338/50 Talbot
it is a trimmed, necked down version of the BMG capable of launching a 250 scenar @ 3700fps

Steve

 

[dave338]

Re: 30-50bmg

so you think in theory it could possibly work?
i am currently getting all the bits together for a 460 steyr,
ive got a slot on my fac for a .50 , 460 and a .30 so finding an action to suit a switch barrels would be a possibility,
the 338-50 talbot according to the cartridges of the world is only about 350 fps faster than the 340 weatherby,
so iam not sure such a small gain would be worth it , except for the fact of having one, and the 460 will hit a lot harder

 

[Wild_Bill]

Re: 30-50bmg

Hi i have a 338-50 chamber reamer. it is based on the 50 spotter that is shorter than the 50 cal case but 50 cal cases can be cut down and used. the balistics of the 338-50 were severly lowered when it was made as the powders then available are not as slow as the ones we have now. it would be possible now with the slowest powders to actualy get a lot higher velocity. I have not done anything with it as i dont have an action i have the reamer and 100 cases but that is where the peoject stopped i would love to see where the case could go it would be awsome with a 300gr match projectile

 

[Greg Langelius *]

Re: 30-50bmg

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> Yet another 50 caliber cartridge is the 50 Caliber Spotter Round. This was built on a shortened 50 caliber BMG case. The case had an overall length of 2". It was intended as a spotter round in tank artillery and occasionally used in machine guns in aircraft. It came into use during WWII and has not been used since. This cartridge uses a shortened 50 BMG case but the rim size of 0.804 inches is too large to fit any shoulder held weapons. Moreover, it will only fit guns already fitted for the 50 BMG.

</div></div>

...more...

...brass...? (unfired primed brass, $300/100)

Personally, I suspect that the neck-down process could be problematic (maybe even horrific).

Greg

 

[dave338]

Re: 30-50bmg

that link for the brass is not working for me ,
this spotter sounds like a good step,
just need to find a supply and also internal dimensions so we could have a guess at velocities
i will stay with the .30 at the moment because its an arse changing my firearms certificate,
cheers all

 

[Greg Langelius *]

Re: 30-50bmg

bigskysurplus dot com.

 

[dave338]

Re: 30-50bmg

greg i cant access that from my computer/server
do you know who makes the spotter brass, in any event i would need to find out who has it in europe/
why do you think necking it down would be a problem?

 

[The Mechanic]

Re: 30-50bmg

You may try biggerhammer they have several guys over there that work with the spotter tracer round.

 

[Rovieairto]

Re: 30-50bmg

There may not be a powder slow enough that is commercially available for a true 30-50BMG.
I would find the slowest powder available and then calculate the maximum case size/projectile velocity combo that would match it.
Then make it a little smaller to give you some breathing room.
Once you know what is really possible then you could proceed.

 

[Greg Langelius *]

Re: 30-50bmg

It was a USGI cartridge, so I'm guessing it was in some supply at some time.

Going from .50cal to .30 cal would appear to be a mechanical challenge of some magnitude, as would be the consequent neck wall thickening.

I can think of better approaches that would achieve the same case capacity with fewer issues. Honestly, the .30 caliber magnums should be roughly similar in capability.

It's long been my conviction that aside from issues of vanity, there is very little motivation to create wildcats anymore.

The main motivations for me would be to provide cartridges with longer necks (which I believe can aid in preserving against throat burnout), and mating a case capacity to a bolt face diameter.

But really, just about any case I can envision already has a functional equivalent being manufactured somewhere.

BTW, I once discussed a .50-20mm chambering with a guy, and the question of powder burn rates came up. I think that's already been covered very well in this topic.

Greg