He has confirmed that the a full flash hider with external locking lugs has the same cone as one with internal locking lugs.
Here's a shot of my source's working MG81 with the above booster-suppressor, mounted on an anti-aircraft tripod:I understand it is one of the rarer parts to find for the already rare MG81 parts.Â I have been fortunate enough to find two partial parts guns over the last year.Â Unfortunately none had the flash hider only the regular booster.Â There are 150-200 mg81 and mg81z (which is the duel version) in the hands of legal shooters or collectors.Â The booster without the flash hider is what most collectors have.Â There cannot be more than a few dozen original flash hider boosters with these guns. I have only seen the version with the outer lugs, with and without flash hider.Â That is except for the two pieces with flash hider that you posted.
There is a booster cone that has to fit inside for a real one to function.Â As an aside to real reason for wanting to copy mine there may be a small market with machine gunners for this piece.
As for the type of steel I will go through my German books and see if I can find exact hardness of steel used in these.Â You also posted asking about how hot the gun gets.Â It gets very hot.Â My gun has been timed at 1830 rounds per minute.Â I usually do not fire more then a 50 round belt at a time.Â Giving the gun barrel time to cool down between firing.Â The gun was made to operate with a wind of 200-300mph flowing over them with an air temp often below zero.
I believe the booster cone is simply inserted before the booster is threaded onto the barrel shroud and it acts as a sort of free-floating gas valve. It's used with both the flash hider boosters and the non-hider boosters, so it's a standard part on the MG81. Given what we know about the bull barrel length, diameter, and how the suppressor was attached, I don't see any reason or room for the booster cone to have been included in the prop, but I could be wrong. In these preproduction photos, the suppressor looks centered:Originally posted by Darth Lars@Oct 17 2005, 07:34 PM
How is the insert ("booster cone") mounted in the muffler? Could this have been used to attach the bull barrel somehow?
I guess you'll know better when it arrives.
Thanks.Originally posted by Lordsandy@Oct 17 2005, 08:11 PM
Well Done .
I didn't imagine I'd have something to say in this thread, but now you touch on the Obi, I do.Originally posted by Prop Runner@Oct 17 2005, 12:32 PM
Notice how the lug notches taper off, and the rounded end is not circular but oval:
That implies that the ball tool that carved out the notches had a spline curve or radiused tool path, as opposed to a linear one:
This is similar to how the notches were cut on the master of the Obi saber grenade before it was investment cast for mass production: the cuts "bottom out" at either end of the grenade using a curved toolpath that takes the tool away from the part.