450Bushmaster.net

I searched a lot and I was not able to find lots of info on how to modify a .223 receiver so one can install a large caliber barrel, in our case - 450BM. So I did it on my own with very little tools and recorded it for others to see. Please take a look and pass it onto others who might be interested in such mod without spending loads of $$$. It is a two-part video:

http://www.youtube.com/watch?v=IhLkrtymmoI

http://www.youtube.com/watch?v=48dGx0YySnE

Cheers,
Mad

Very nice! Great job, thanks. Had to save it to the computer to add to my .450 data drive.

Cool, thank you.

If you don't mind, I'll add a link to that in the knowledge base.

MudBug wrote:Cool, thank you.

If you don't mind, I'll add a link to that in the knowledge base.

Not at all. I hope it could help someone else on their project.
Thank you.

Cheers,
Mad

the_mad_rshn wrote:I searched a lot and I was not able to find lots of info on how to modify a .223 receiver so one can install a large caliber barrel, in our case - 450BM. So I did it on my own with very little tools and recorded it for others to see. Please take a look and pass it onto others who might be interested in such mod without spending loads of $$$. It is a two-part video:

http://www.youtube.com/watch?v=IhLkrtymmoI

http://www.youtube.com/watch?v=48dGx0YySnE

Cheers,
Mad

Way-to-Go-Mad!! This is very good and I might say, you do a better job than I. I don't use tape and need to.

Some observations, not criticisms, none at all, no-way.. Mad uses tape, I don't, you can tell from this, he is smarter than I. The reason for tape is evident, when he started to use the stone he nicked the cartridge deflection knob on the receiver, and because he uses three layers of tape, nothing bad happened.

Also, on the beowulf and socom, the case is just fat enough that those outfits had to eliminate the Ejection Port Cover entirely and the cover lip itself, located on the receiver (there is no receiver detent to secure the door after the grinding), to accommodate the larger case. The lip for the Ejection Port Cover(located on the receiver itself and the top of the receiver port ), that keeps the cover from swinging into the receiver, has to be totally eliminated (saying it a couple of different ways might make my English Profundities, more understandable)...."BUT" for the 450, none of the bottom portion of the port needs any grinding and only the forward half of the Ejection Port Cover-Lip needs trimming back to the receiver boss (making a natural and obvious stopping point if this is to be a dedicated job for the 450b only) and if you leave about an eighth inch on the chamber side of the Ejection Port Cover-Latch-Detent (located on the receiver, in and on the top of the Ejection Port), the cover can be reinstalled and used as normal, keeping the bugs and such out of the action, this is exactly the recipe Bushy uses as recommended by me, in the early days of this R&D work-up, those other big bores do-not have this luxury. This is one of the main reasons I went with the 284 case diameter, coupled with the fact that the 284 case is also a modern high pressure rifle case (sammi spec in the 63,000psi area, for factory everyday working loads) as opposed to the stretched 50AE case (sammi spec in the 35,000psi area) of the others, which in large part holds them back on any real serious developments.

Good job, MAD, it's going to be great to read your posts. I look forward to your edification..

Great point about the difference in diameter for all three of the "big boys", Wildcatter.
I just hoped that someone can see the technique of how it is done and then apply it to their own caliber

Cheers,
Mad