thanks to you guys that bothered to post in!!!
I forget the exact size hole but it is much bigger than the diameter of the bullet. no I do not want the bullet to bounce around inside their. The brake is a larger diameter so it has a larger diameter hole in it. the hole in the brake is 1,7/8" deep and just over 1/2" diameter. I am telling myself , if it was not safe their would not be all those AMD extentions out their. I hope....
as for attaching the extention. this is my plan SO FAR.
the end of the extention and nut have beed tapered to accept a fill weld
#1, turn a shaft about 10" long, it will fit down into the barrel about 4".their will be a step in the diameter and the rest of it will fit through the extention. the fit will be a nice fit hopefully zero clearance but not tight. this will hold the extention in align. then it will be nocked out up through the barrel with a smaller diameter rod.
#2, put the barrel nut on snug to the end of the barrel to cover the threads. it will go on backwards to give a heavy end against the extention for welding.
#3, slide the thin end of the alignment rod into the barrel.
#4, push the sight base on the extention, then slide the extention down onto the alignment rod.
#5, turn the extention to position the holes ware I want them, and one tac weld extention to nut. cool.
#6, tac weld the opposet side, cool
#7, now with a tac weld on top and bottom I will tac both sides cooling between each one. now I can continue to do small tac welds , cooling between each one.
#8, unscrew extention with the nut to be shure no weld had flowed through, if any dimpels have flowed through they can be drilled out now easy.
#9, screw extention back on and conferm alignment with the pin. adjust if needed.
#10, now finish the weld with a lot of stops for cooling.
#11, unscrew again , chuck up in lathe and do whatever is needed to make the weld area invisable, turn , file, sand. whatever.
#12, screw back on tight with holes in desired finished position, check alignment with pin.
#13, drill two holes through nut deep enough to make dimpels into the threads on barrel, unscrew extention and tap holes, screw back on and put in set screws to hold perminatly. weld over set screws.
#14, position front sight and reinstall mount pins.
this is the same set screw, method I allways use for mounting a brake.
doing it this way all I have to do is drill out screws and I can remove the entire extention with no loss to the original parts!!!
I am going to buy a nice scope just like my romak and install it on the extra mount that came the romak..HOWEVER,, I am not going to buy it till I get a bunch of rounds through this extention. that way if it fails I will take it off and forget the scope and the hole thing. Also I do not expect exacting groupings and that is fine with me ,, however if it groups out to 6" at 50 yards I may trash the extention idea too. so I have a lot of rounds to fire just checking grouping patterns. I think it will be ok.
boy I had hoped more guys would post in with oppinions. thanks again to you that have helped so far.
Sorry for the long post but I could not explain it in 3 lines.