Ok, mark clearly must be creating accounts just to comment on his video.....no real person would fucking write this.
....there is no way these are not Mark Serbu.....
....there is no way these are not Mark Serbu.....
Ok, mark clearly must be creating accounts just to comment on his video.....no real person would fucking write this.
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....there is no way these are not Mark Serbu.....
Hell, he already uses his daughter in his videos...Hi,
I would point his legal team to update themselves on this...
"Thank you handsome", lolololol is he hiring out of work showgirls to write reviews, lol?
Sincerely,
Theis
Can't tell from that photo, but where (if any?) are the gas venting holes or other safety features that would prevent this pipe bomb looking contraption from doing what it did to KB again?Probably something they might want to remove from the website also...
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There are things in this world that you can simply look at and confidently boast "look at that build quality and attention to detail". It doesn't take a degree in mechanical engineering to look at that weapon and make judgement there.
SHTF 50 is another death magnet out there, along with Noreen. Not my personal opinion, it's proven fact.
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Umm, no thanks - I'm good! With a string for the YouTube views and good vibes, sure... I guess?
There are none, according to mark serbu, the RN50 doesn't need "secondary safety features"Can't tell from that photo, but where (if any?) are the gas venting holes or other safety features that would prevent this pipe bomb looking contraption from doing what it did to KB again?
Can't tell from that photo, but where (if any?) are the gas venting holes or other safety features that would prevent this pipe bomb looking contraption from doing what it did to KB again?
Definitely the latterWhat I find additionally frightening is that if you follow his latest vid to YT and look at the comments below, they are all glowing compliments for this guy, this gun, and his "analysis" of its safety, and his openness and transparency.
He HAS to be editing the comments and deleting those he doesn't have. Either that or, based on those comments, humanity is doomed due to abject congenital stupidity.
I was talking about the RN-50.There are orange plugs on both sides of the action, and also on the bolt body for venting gas. Of course nothing guarantees those will help in every type of situation, but it is a path to safely get that gas pressure vented.
Check out post 174 in this thread I linked below for an example of operation (and a missing pressure port from a ruptured case).
https://www.snipershide.com/shootin...e-actions-which-fails-more.40644/post-1016887
EDIT: Wait, you talking about the RN-50 or the AW-50?
The RN-50’s only safety feature - it’s $1200, who cares, just buy it!
Oh yeah, nothing at all unfortunately. In fact, it’s probably relatively easy to replicate I would say.I was talking about the RN-50.
or just do one of those capless fuel doors so there is nothing to fly back into the shooters face when it explodesYo Marky here's a free upgrade idea. Make the cap click like a gas cap does to ensure its torqued properly....for safety.
I'm not a welder but Damn that's a lot of undercut on that back weld. Looks like it was tig welded with no filler wire. I doubt that would pass a pipe welding test, forget about it being on something capable of producing 60,000 psi inches from your faceProbably something they might want to remove from the website also...
View attachment 7623933
There are things in this world that you can simply look at and confidently boast "look at that build quality and attention to detail". It doesn't take a degree in mechanical engineering to look at that weapon and make judgement there.
SHTF 50 is another death magnet out there, along with Noreen. Not my personal opinion, it's proven fact.
View attachment 7623944
Umm, no thanks - I'm good! With a string for the YouTube views and good vibes, sure... I guess?
If you smoke a bowl before you start welding you don't need no stinkin filler.I'm not a welder but Damn that's a lot of undercut on that back weld. Looks like it was tig welded with no filler wire. I doubt that would pass a pipe welding test, forget about it being on something capable of producing 60,000 psi inches from your face
for proper tread/attachment strength there is a specific torque value that the cap needs to be applied with, that’s mechanical engineering 101. It’s not just material strength.
To get 160k + shear strength, you are factoring that the thread engagement is 1.5 times the circumference, and that the thread is properly torqued. Being in Tool and Die, I've seen a lot of failures and can tell you that the 2 lugs on the receiver would have been better off case hardened or soft. The fact that they sheared/broke off is very troubling. You can point all the fingers you want, but sometimes in manufacturing.... designs have flaws. It's how we get better/smarter as a Society. Not too long ago, drag racers were sitting on top of their top fuel transmissions. You learn from mistakes and move on....
so 1.5-12 threads at 1.5x thread engagement would give us 2.25" of thread required.....or 27 threadsTo get 160k + shear strength, you are factoring that the thread engagement is 1.5 times the circumference, and that the thread is properly torqued. Being in Tool and Die, I've seen a lot of failures and can tell you that the 2 lugs on the receiver would have been better off case hardened or soft. The fact that they sheared/broke off is very troubling. You can point all the fingers you want, but sometimes in manufacturing.... designs have flaws. It's how we get better/smarter as a Society. Not too long ago, drag racers were sitting on top of their top fuel transmissions. You learn from mistakes and move on....
Based on what I’ve seen I think you are giving the man far too much credit.I was going to post the same a day or so ago but it’s almost not worth it.
He doesn’t know the difference
Everything we are explaining will only give him a better product...when he should be closing his doors
NERD!!!!!I am a mechanical engineer so this stuff interests me. In my experience, well done back of the envelope calculations will get an answer that is in the general ball park of the truth. Here is my attempt at a back of the envelope calculation to determine the amount of chamber pressure it takes to shear the threads.
Assumptions:
1. Barrel steel that is quoted as "30 Rockwell C" has an ultimate tensile strength of 148 ksi.
2. Shear strength is ~60% of ultimate tensile strength so let's assume 89 ksi shear.
3. Assume the case head fails and that the gas impinges on a surface area on the threaded cap that is about the same as the thread max diameter so 1.5 inches round. So an area of 1.77 inches squared.
4. A total of 4 threads failed under shear load.
The threads have a root width of .068" and a root diameter of 1.38" then one thread has a root area of .295 inches squared. 4 threads together have a total root area 1.18 inches square.
The equation to satisfy should be:
(Chamber pressure)*(surface area of the cap)=(shear strength)*(root area of the threads)
Solving for chamber pressure I get ~59,000 PSI to make the threads fail. This is only if the case head fails and gas impinges on the full rear surface area of the cap.
If the case doesn't fail and only the case head is pressing rearward on the cap I get a pressure in the case of 208,000 PSI to make the threads fail.
In one of the pictures of the barrel in Mark's video you can clearly see the rest of the case left in the chamber. A classic case head separation is what it looks like to me.
These calculations would only be the start of determining if a design was feasible. A good 3D modeling program with built in FEA would be the next step. If anyone sees a glaring error please point it out and I'll edit the post.
Looks like a tack driver. KO2M here I come...lulz
Looks like a tack driver. KO2M here I come...lulz
I heard that this version was gonna be a muzzle-loaded, smokeless powder, matchlock system. Due to the pesky primer shortage and all the 'forward thinking' involved in development.
I may be thinking incorrectly (pretty tired atm) but wouldn't this be the case assuming the failure was by the threads stripping? Haven't studied the pictures in detail but seem to remember the ones I saw looking more like the threaded area sheared off in the valley of one of the threads (point of minimum material cross section).I am a mechanical engineer so this stuff interests me. In my experience, well done back of the envelope calculations will get an answer that is in the general ball park of the truth. Here is my attempt at a back of the envelope calculation to determine the amount of chamber pressure it takes to shear the threads.
Assumptions:
1. Barrel steel that is quoted as "30 Rockwell C" has an ultimate tensile strength of 148 ksi.
2. Shear strength is ~60% of ultimate tensile strength so let's assume 89 ksi shear.
3. Assume the case head fails and that the gas impinges on a surface area on the threaded cap that is about the same as the thread max diameter so 1.5 inches round. So an area of 1.77 inches squared.
4. A total of 4 threads failed under shear load.
The threads have a root width of .068" and a root diameter of 1.38" then one thread has a root area of .295 inches squared. 4 threads together have a total root area 1.18 inches square.
The equation to satisfy should be:
(Chamber pressure)*(surface area of the cap)=(shear strength)*(root area of the threads)
Solving for chamber pressure I get ~59,000 PSI to make the threads fail. This is only if the case head fails and gas impinges on the full rear surface area of the cap.
If the case doesn't fail and only the case head is pressing rearward on the cap I get a pressure in the case of 208,000 PSI to make the threads fail.
In one of the pictures of the barrel in Mark's video you can clearly see the rest of the case left in the chamber. A classic case head separation is what it looks like to me.
These calculations would only be the start of determining if a design was feasible. A good 3D modeling program with built in FEA would be the next step. If anyone sees a glaring error please point it out and I'll edit the post.
I'm not sure what the difference is between the threads "stripping" and the threads shearing off at the root. The threads certainly sheared off at the root which is the point of maximum thickness.I may be thinking incorrectly (pretty tired atm) but wouldn't this be the case assuming the failure was by the threads stripping? Haven't studied the pictures in detail but seem to remember the ones I saw looking more like the threaded area sheared off in the valley of one of the threads (point of minimum material cross section).
Like I said, my brain isn't firing on all cylinders at present. Either I mis-thought or not awake enough to put my thoughts properly in writing. Will try again in the morning...I'm not sure what the difference is between the threads "stripping" and the threads shearing off at the root. The threads certainly sheared off at the root which is the point of maximum thickness.
I may be thinking incorrectly (pretty tired atm) but wouldn't this be the case assuming the failure was by the threads stripping? Haven't studied the pictures in detail but seem to remember the ones I saw looking more like the threaded area sheared off in the valley of one of the threads (point of minimum material cross section).
I'm not sure what the difference is between the threads "stripping" and the threads shearing off at the root. The threads certainly sheared off at the root which is the point of maximum thickness.
Mordamer I think you are talking about threads shearing off at the rood like the left side mark.Like I said, my brain isn't firing on all cylinders at present. Either I mis-thought or not awake enough to put my thoughts properly in writing. Will try again in the morning...
Hi,
Is that their new QD barrel extension for the CheyBoom??
Sincerely,
Theis
No. Thats the aftermarket. This is the one for the CheyBoom.Hi,
Is that their new QD barrel extension for the CheyBoom??
Sincerely,
Theis
Still incorrect. This is the extension. Built in shear lines.That's the chamber extension to shoot 20mm ammunition.
I'm pretty sure that is the chamber insert to adjust throat depth for slap rounds.Still incorrect. This is the extension. Built in shear lines.
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Indeed what I was thinkingMordamer I think you are talking about threads shearing off at the rood like the left side mark.
Numedal I think you are thinking it would rip like the mark on the right side through the valley.
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There is an update from Serbu himself.