I have a 30" Bohica 50BMG upper for a AR with a big brake and the first trip out I shot it 39 times. Your brake makes all the difference. I just got a down sized clamshell 50-BMG style brake pIut on a new 338 Rem. Ultra Mag bolt gun that has a #5 profile Lilgi barrel and is a Huntable weight. I'm shooting it in the morning. The brake came from boys50bmgatr.com you can scroll down and see the after market brakes. It sure looks like it will work good. I'm new, but if I knew how to post a pic, I would.
I shot my new 338 Rem. Ultra Mag today with the new brake. I haven't weighed it yet but would guess less 11-11-1/2 lbs. with that brake it kicked like a 243 at best. I had loads to try and shot 45 rds and it was pleasent and fun to shoot. Your brake is your friend, wear your ear protection and have fun shooting. My 50 BMG Bohica upper with HOT 750 A-Max loads kicks like a regular 7mag.
I can not tell you the technical side of it but it looks like that has all ready been covered. I own an AR50 I shoot it and even with the 750 gr match rounds it is very pleasant to shoot if you are the shooter on lookers on the other hand if they are to close well not so pleasant. My girl friend shoots it and giggles every time , she loves the rifle. Not to be crude but I think she gets more pleasure from the AR50 than she does me if you know what I mean. I had the chance to shoot an EDM and even with ball rounds it was very uncomfortable to shoot and after about 5 or 6 round I was done and hurt for several days. If you are looking to purchase a 50BMG I suggest you do your home work. I would recommend the AR50 but would pass on the EDM. I have had no other experience with any other 50. I have seen the Styre and the muzzle break was a bit smaller than the AR the EDM was very small. Good Luck Hunting
from what ive heard and seen on TV the barrett M107 and 82 models have a kick 3x stronger than that of a 12 gauge magnum. a soldier on a documentary i watched said his shoulder was very sore after firing 25-30 shots from a barret M82 .50BMG. the big fifty is not for the faint of heart. if you're going to fire a .50BMG rifle be sure to have something between you and the gun stock. even with the barrets factory made kick pad its not enough. and to tell y'all right now the barret doesn't have the strongest recoil, the .700 nitro express T-rex rifle kicks so hard that its sends the user flying back 4-5 feet and often loses grip and the rifle making the gun fly right up out their hands