reloading the .17/50bmg Magnum

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lykoris

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With today's modern trend of shorter, fatter, and faster rounds, our staff has developed what may be the ultimate varmint round. It will far exceed both the WSM and WSSM rounds in both range and velocity. We would like to introduce the .17/50BMG Magnum. (see photo attached below)

The new round is based on the 50 BMG necked down to .17 cal. with an innovative shoulder configuration to allow additional powder space. Unfortunately, the round will not be able to be reloaded to factory velocities until we can develop a home-use powder drop that will adequately fill the shoulder space. It has been suggested that the load be assembled in reverse, with the bullet first being seated and the powder then poured throught the primer hole. We are now testing that proceedure.

The .17 cal. projectile is a specially designed 45 gr. varmint bullet. The staff sacrificed a slight bit of velocity with this heavier bullet in order to get an increased ballistic coeficient for added downrange stability.

We started development with 200 gr. of Hodgden H50BMG powder but found it to be a bit slow burning for maximum velocity with this light bullet. 205 grains of IMR4831 seems to produce the highest velocity but we won't know for sure until we find a chronograph that registers above 9999 fps.

Close range accuracy with our prototype rifle was .3 MOA. Further refinement of the rifle should dramatically improve on this poor performance. We fired a group at maximum range yesterday then sent a team to recover the target. They should be back tomorrow to report on long range accuracy.

Finding a scope with enough magnification to see small targets at maximum range has been a challenge. We finally settled on a Swift atronomical reflecting telescope which will provide suitable magnification of ground squirrels at 3 miles. However, being a reflecting scope, it has it's drawbacks. The image is inverted and, with the eyepiece being near the front and at 90 degrees to the scope, it's a bit uncomfortable to hold and sight the rifle. We feel that the unnatural shooting position is the cause of the less-than-ideal accuracy with the prototype rifle. On the plus side, the exceptional velocity of the round allows a 1.5 mile sight-in and allows the shooter to hold dead-on at twice that range.

It's well known that large capacity, narrow bore rounds tend to heat a barrel rapidly, causing premature throat errosion. This round, being large capacity and narrow bore to the extreme, tends to heat the barrel very rapidly, as expected. With the prototype, we find it unadvisable to fire more than two rounds per day in the winter, one per day in hot weather. This gives the barrel time to cool between shots. We have a second generation prototype under development that uses an environmentally correct R134 cooling system that operates from a backpack unit. It is designed to permit sustained rapid fire of one shot per hour.

We tested the new round on a coyote at about 2/3 of it's maximum range. The coyote was feeding on a rabbit when the shot was fired. However, before the bullet arrived, the coyote finished eating and wandered away, causing a miss. We recommend shooting only at sleeping coyotes unless it's either caught in a trap or already dead.

Retail price has not been established. Duplicate prototype rifles are available for those who wish to get in on the ground floor of the hottest round ever developed. We will gladly take trade-ins if you happen to have a low mileage Porche, 1998 or later. First born children are not accepted unless house broken and vaccinations are current.


 
I think if you seat the bullet out a bit more, you would get more powder space and perhaps a little more velocity.
Good thinking using the R134A, that will reduce the time for a follow up shot, should you actually need it.


NCsmitty
 
Hey Lykoris,

You are obviously behind the times. Up in Perry County, PA, they are using the same 17 cal bullet in a necked down 20mm Vulcan case. Supposedly, the Perry County women complained about the recoil on their regular 20mm bolt action rifles and found the 17 cal bullet a bit more to their liking.

Best wishes,
Dave Wile
 
Can I get a AR upper for it?
Would you get a 16" or 20" barrel?
Chrome lined?
Will it shoot Barnes QuadX bullets?
Does it have to have a magnum primer if I reload?
Will the mag primers cause stuck cases in my dies?
Will it recoil more than my .14/ 50 Browning?

JK
 
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H*ll! That round looks like childs play.

Back in the 70’s they developed the 50-BRBR. They used the main barrel from a Battleship turret and progressively sleeved it down to 50 cal. They developed a 30 gallon brass case, and measured powder in by the bag (10lbs/bag). The barrel was rifles for only 2 feet and then smooth bore after the rifling which allowed gasses to bypass the bullet. This releaved pressure and accelerated the bullet via Bernoulli’s Principle.

The round was never intended for accuracy because the shock wave generated would completely devastate a 600 meter wide path, which narrowed a bit after 2.566 miles and stopped entirely when the bullet finally disintegrated after about mile 3.17 to 3.42.

Oh yes! The BRBR stood for Battleship Rifle Battleship Required.
 
I have a way to work around barrel errosion. Just go up to the next caliber size every third round. Or go with the water jacketed barrel and get 5 shots before you move up to the next size.
 
The 17s are know for really fouling the bore, I would suspect that this wildcat would require a complete and thorough cleaning every 3 and 1/2 shots.
Handloader Magazine had a fun article about 25 years ago detailing a wildcat similar to this one, it was the .045-50BMG. Fired a needle!!!!
 
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"205 grains of IMR4831 seems to produce the highest velocity but we won't know for sure until we find a chronograph that registers above 9999 fps."

Bet that sucker would really scream if you loaded maybe 195 gr. of IMR-4227, modifiy the primer pocket to accept shotgun caps and have Lee make you a Factory Crimp Die for it.
 
.....(hurting from bumping my head on keyboard laughing):what:

If this round is fired through a squish barrel then the round will exceed the speed of light.:neener:

This round will also beat a Star Wars rail gun hands down. Sheesh, it did not take a few billion $'s to develop either!:banghead:
 
geez, that thing just looks plain silly. i wouldn't want it based on its looks alone.

you ackley that bad boy, though... now we're talkin'! little extra capacity, little bit longer lived brass, and looks to boot!
 
What barrel length are we talkin here ? will it fit in my Suzuki Samurai ???
 
I had my machinist buddy make me a 17/50BMG barrel for my Glock, but we could never get it to feed rounds from the magazine so I sold it.
 
Good thing you put that 4.6 X 30 in there for comparison or I wouldn’t have known what I was looking at. Can you hunt deer with that?
 
Only 205 grains of IMR4831 and maybe 10,000 FPS?

It is common internet knowledge you load book developers don't tell us the real max load for legal reasons, and fudge downward by at least 10%.

I bet a starting load of 225.5 grains is more likely the real truth!

rc
 
I'm wondering now if we have been expanding in the wrong direction. How about a case that's about the size and shape of a Skoal can? That way it would work in one of the new super short actions but still have sufficient excess capacity. Maybe a rimfire since it would have a bunch of extra rim too?

I'm just saying.
 
I bet a starting load of 225.5 grains is more likely the real truth!

Now careful there! Don't want to go making a compresed load!

Yeah...compressing that near 1" diameter powder column with the base of a .17" bullet...


Brings up a mental picture of someone trying to "compress" a haystack with the end of a broomstick. :D

-Sam
 
I would concur that it is a bit overbore. Perhaps using the somewhat shorter and thus more efficient .50 Spotter case would mitigate the potential for throat erosion.
 
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