300 Raptor, first results....

Mr. Allen, I remember reading a post of yours from wayy back, and I think you said something along the lines of the 300SMK having a higher than posted BC when shot from your AM, you said you had to use like a .9 or something like that to match the trajectory you were getting, is that correct or am I dreaming?

Also, just curious, but what performs better ballistically between the .510AM and .338AM both with the highest BC available?

I just wanted you to know I am going to order a .270AX or .300, one day....I am only 18 and in college atm so $$ is low but I am really considering saving school for later as I got a 92 out of 100 on the ASVAB(I could pretty much choose whatever job I want) and want to do infantry in Army or Marines, I can go in with a special forces contract in the Army and get a free shot at Ranger school and possibly even further(Green Berets, etc). So obviously I aint in the position to buy anything right now but please dont retire for atleast another 5 years or so so I can experience the greatness. Ive wanted to join my whole life but my mom has always tried to dissuade me because of the grades I got in school, but man Im at the peak of my years I do not want to sit behind a desk.

Also, have you ever considered doing a .375-50BMG(Im sure you have)? Why didnt you go with that as the parent case, must`ve not gained much over the .408 case I assume? I imagine you know Dave Viers? How do you think the .375 Viersco Mag would compare to .338AM?

I swear Im not trying to derail but the thread seems dead, any updates on the Raptors?
 
You remember correctly that I was using a higher then listed BC but it was not that high. Generally for my 338 AM I use .820 compared to the listed .780.

Comparing the 510 AM to the 338 AM, looking at bullet drop, the 338 AM winds dramatically, wind drift is similiar between the two. Kenetic energy certainly is in favor of the 50 cal. Shootability, strong in favor of the 338 AM as its warm and fuzzy to shoot, the 510 is well, an EVENT to shoot!!!


Going into the armed forces is certainly a great thing but I would also recommend you get your schooling done as soon as possible. It seems to never get done if you do not do it right away. College is not for everyone and you really need to be smart about it. By that I mean go into a degree that will offer you good job opportunities when you get done. How many millions of people out there have business degrees and never use them!!!! Do something you enjoy that will actually get you a job afterwards.

Again, the military is a great choice for sure as well.

The mid calibers on the 50 BMG are really more novelty then anything. A 375-50BMG just does not offer enough barrel life to be practical. PLus you have to chamber it in a 25 lb class rifle minimum. You can take 10 lbs off a 375 Allen Magnum rifle and get within 100 fps of the huge 375-50BMG with dramatically longer barrel life.

Dave has some interesting rounds for sure. I would say the 375 VM and my 338 AM would be nearly identical in ballistic performance with a slight edge going to the AM depending on what bullet was used. The 338 AM gets there with less fuss though.

The Raptors are going very well. Main hang up is simply brass. Working with Bertram to get good brass made, just takes time.
 
Thanks for the replies sir, whenever you got the .408 cases, what was the initial capacity and the capacity after you improved it? (Hope Im not asking too much as I know you like to keep certain things classified)

Also, when I hear people say the .50 BMG is already overbore without necking it down, how overbore is it? What round would you compare to the BMG as far case capacity/bore size?
 
The Term OVERBORED is a term that is used way to often by people that really should not be using the term. The term overbored would be a relative thing, compare to what. Its really a meaningless term that is used to label high performance chamberings and generally by those that do not care for them.

TO get a certain amount of performance, you need an engine large enough to get the job done with the correct amount of pressure.

To say that the 50 BMG is an overbored cartridge is silly. It actually functions extremely well and has a very long barrel life. In fact with the commercial precision rifles chambered in the 50 BMG, you would be hard pressed to burn a barrel out unless you intentionally were trying to do just that.

Now the 50 BMG may not be the most efficent case design in the world but it was designed almost exactly 100 years ago. Back then, they did not have the powders we have today, as such they needed to use a very large dose of the powders they had on had at that time.

Today, we can match the same performance of the standard 50 BMG with a round that uses nearly 60 grains less powder and in a much smaller case design.

To me personally, the term overbored means that you get to a point where expansion ratio is so low that smaller rounds will produce the same velocity level as a larger chambering so in effect your wasting powder for no real improvement in power.

FOr example, a 375-50BMG will only beat a 375 Allen Magnum but around 100 fps, for the added 100 grains of powder you would need in the BMG wildcat, its really a waste of time.

Now some will use my own definition and say that my 375 Allen Magnum is overbored compared to smaller chamberings such as the 375 RUM and 378 Wby but that is also silly, yes you use 30 to 40 grains more powder in the Allen Magnum but you also gain 300-400 fps more velocity with same bullet weight over the smaller chamberings, dramatic increase in power.

So in my opinion, th term overbored is used WAY to often by people that really have no idea what it means and in most cases just do not like or understand extreme performance chamberings.

As far as the increase of my wildcats over the standard Chey Tac or Sniper Tac design, its roughly 10-12 percent increase in case capacity.
 
Fifty

I'm intrigued by the .338 Raptor project, to put it mildly. Just thinking ahead about long term setup to support it, what size press are you loading with - magnum sized or a BMG? I'm not sure the length of the finished cartridge will fit in my Hornady AP.

I may have to drive over from Eureka to Ft. Shaw and torture myself...:D

thanks
 
I know that the RCBS Rockchucker Supreme press works well. This is the newer model with the 1" taller window. Its tight but there is plenty of room. The Redding Ultramag press is also a great one.

That said, the RCBS Ammomaster and Hornady equivelent works great as well but you do not need it.
 
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