Promised pics of the 510 Allen Magnum...

[Guest]

This is the first time my four 50 BMG's have felt insecure /ubbthreads/images/graemlins/frown.gif

 

[THOMAST]

Fiftydriver, when you work up a load, what do you consider to be an acceptable standard deviation and extreme spread?

 

[Fiftydriver]

FOr a 50 cal I like 20 fps or less if possible. Some 50s will simply not do this but I suspect the Lilja barrel on my 510 AM will.

IT seems to be more difficult to get a big 50 cal to get true single digit extreme spreads. I go by extreme spreads, not standard deviation. The reason is because you can have a 15 shot string with the vast majority of rounds producing a single digit SD but have a couple rounds really fly out of the group velocity wise.

Personally I feel extreme spread is a better figure as far as telling you if your load is a good consistant load. Just a personal thing. When either are used correctly they both serve the same purpose. Its just alot harder to get a true single digit extreme spread compared to standard deviation.

Kirby Allen(50)

 

[Northman]

Picture request..

Could you take a picture of your 338 Allen mag cartridge inside the loading port of that AR-50? Just to get the sence of how big that action is? I have read is was made for the 20mm Hispano(??) cartridge, wich is larger then the BMG.

 

[overbore]

Fifty, great engineering. I like your bolt travel solution
and will apprciate a contact when you get some long range accuracy results for an order. As a user of long heavy tubes myself, a vented bedding block solution appears to eliminate any action flex for me, makes bedding dead-easy and may, by increasing the mass of the rifle, further reduce the recoil when you hit 2,950fps. Well done and Congrats! Overbore /ubbthreads/images/graemlins/cool.gif

 

[Fiftydriver]

Norhman,

Here is the pic you wanted.

Kind of makes the 338 AM look like a 22-250 AI or something like that!!!

I am not sure if the receiver was designed for the 20mm Hispano or not. I do not think the bolt face could be opened up that large or not. I did hear that it was designed to handle the longer 50 Russian round which is a bit longer then the BMG.

Good Shooting!!

Kirby Allen(50)

 

[jimmym40a2]

could you post a picture of the case it's self. I've been reading these post but want to see the case it's self and one with a bullet in it. perhaps next to a 50bmg case thanks.............

 

[SUNDEVIL]

That action looks huge! One of the 50's I shoot is a McBro's, it has a 30 inch lilja. I get 2820 with the 750amax. Im dying to see what u kick the velocity up too!

 

[Fiftydriver]

What load are you using to get 2820 fps with the 750 gr A-Max. I have shot alot of 50 BMG rifles with this bullet and in a 32-36" barrel length, all have limited out at around 2700 to 2750 fps with proper pressures for the 50 BMG, that being, being able to rechamber a fired round with no real resistance on the bolt when you close it on the fired case in the chamber.

I have run them over 2900 fps so far with decent results but thats starting to move the brass quite a bit and resizing takes some effort.

Kirby Allen(50)

 

[Ridge Runner]

WOW

I am pondering building a 20 tactical, thought I'd check kirby's post out......boy do I feel inadequate!
RR