Short action 50 caliber rifle integrally suppressed. Let's discuss!

[MTFalconer]

So I have had this on my mind for quite a while. Never done anything with it, just the idea and I think it's time to explore the concept a little further. So here are my initial thoughts and keep in mind I have most of the materials to build this thing in house and I am a machinist. Goals: .510 bullet, short action, magazine fed, integral suppressor barrel...

The case I was looking at is the 7mm short magnum. This would allow it to but used in any of the short actions without rebating rims or anything crazy. Cut the shoulder off the case. It has an external diameter of .543, not sure what the ID is but I am sure it could expanded to .510 with a custom die if not really close. Resulting in a straight wall case. Adjust overall length with the larger bullets to feed in a short action from a short action AICS magazine.

Love to hear some mechanical thoughts related. I have not gone to the effort to spec anything out, at this point it's just an idea but I think it would be fun to play with as a relatively short range hunting rifle. In the end, all it needs is enough powder capacity to reach 1,000 FPS. Anyone have any other parent cases to consider? I would love to bounce some ideas around in this space.

 

[2c1fr]

Ttrl

 

[hic28]

Just chamber a short action for .450 bushmaster, feed from aics mags and shoot 250gr at 2400 fps or 230gr at 2800.

 

[MTFalconer]

I'm guessing you missed the part of .510 bullet, suppressed and 1,000 FPS.

 

[Ledzep]

I think what you're describing is the .50 thumper.

I've made a dummy round before, but never seriously pursued it. You cut a 300wsm case off at the shoulder and trim to length, then debur/chamfer and plug a .510" bullet in it. It really depends on how heavy a projectile you want. If you're looking to shoot 600+gr ball or solids like what you'd shoot out of a 50bmg, you're going to probably have to go long action because of the relatively massive ogive length. Or cut the case shorter and MAYBE get away with it in an AICS pattern magazine

 

[Ledzep]

Here's an API bullet in an ARC magazine; you see not much room for a case.

 

[MTFalconer]

I had not heard of that one! Is the ID of the case close to .510? I had not considered the 300 was but I sort of figured the short magnums would produce a case capacity usable to get to 1k FPS. I am not beyond a single shot build but I honestly want to see it mag fed.

 

[Ledzep]

It is fairly close. A little bit of a bulge around where the bullet is seated. Unfortuately I don't think I have the dummy anymore. I like using the API bullets as reactive targets so I think it got shot.... but my feeling about it was that after the first fire-forming shot, and with appropriately sized dies/chamber, it would work out pretty easily without having to ream or turn anything.

 

[MTFalconer]

I have some molds for lead cast .510 bullets, on them I can control OAL of the bullet fairly easily. ONe is a custom mold I had made up recently to powder coat solid lead cast.

 

[Geno C.]

Not a short action but look into the 500 whisper. Uses 338 Lapua brass as the parent case

 

[MTFalconer]

I have built a few of the 500 and .510 whispers. I liked them but would rather build something in a short action, just for fun.

 

[ohiofarmer]

Have you looked at the .510 Beck? It might fit the bill when it finally gets released.

 

[MTFalconer]

I did, I saw that cartridge recently and I believe it might be a proprietary case, Looks promising.

 

[hic28]

I'm guessing you missed the part of .510 bullet, suppressed and 1,000 FPS.

Missed the 1000fps part haha. It would be significantly easier to use a .450 bushmaster case and do a huge lead cast 700gr under 1k.