Will A 357 Max 1-16 Twist Stabilize A 180 Gr Bullet
300 Gr 358 cal bullet mold #358-30-GC357 Liberty Max or 357 Liberty Whisper-MAX. Regardless of the name, I think a real winner is possible.It's time for Dave to turn the silencer world up side down and blow the Whisper folks out of the water by coming up with a 9mm-357 mag silencer that is take apart. Can use a booster, and use the AAC TRIAD for a trilug mounting for fast attach and to add an extra steel blast baffle.Make a tube strong enough to handle the 357 mag pressures or if possible the 357 max pressure.
In a longer barrel 10'+ or more you could load the 357 MAX brass with the LONG heavy bullets subsonic and be within 357 mag pressures.The Maximum brass is VERY easy to reload as it is a straight wall case so you can use carbide dies. Hello JohnI believe you. I think this will be a fun project to work on. What size parameters do you think will be acceptable for this package? I need to know what size 'box' I need it to fit before I start. I can see already that we will be needing to make some of it out of titanium as well as stainless steel an aluminum.
We might even entertain the idea of using some inconel on the blast baffle if you think erosion will be a problem. Can you provide me with the load data that you use on the full house 357 maximum loads so I can see how much powder we are dealing with?
That seems like the best place to start.What do you think? If we build it to handle the max, it should be fine on the sub cal stuff too. I don't mind using the triad either. I have bought several from AAC in the past for my customers that wanted them. So that is no biggie. Let's get this party started!!!Dave.
Dave,THANKS for answering my post. I do want you to rebuild my Evo-9 and will call you about that on the phone to discuss what we can do with that (keep Triad ability, upgrade to a SS blast baffle etc.)Back to the 357 MAXIMUM/MAGThe heaviest I have loaded so far are the 200 gr Sierra.358 dia rifle bulletI use 22.7 gr of 296 for 1750 fps or 24.7 gr of Win 680 1800 fps with the super 14' In my 10' barrel I loose about 75 FPS. This bullet CAN NOT be loaded in a revolver.
The TC chamber is LONG and you can load heavy long bullets.And the Speer.358 dia 220 Gr flat nose. Win 680 21.5 gr for 1544 FPS, H110 21 gr for 1620 FPS, Win 296 20 gr 1552 FPS,158 gr pistol bullets: H110 23.5 gr for 1940 fps, 26 gr of reloader 7 = 1845 FPS, Win 296 28.5 gr for 2105 FPS (speer data)These are stiff high pressure loads using MAXIMUM brass & Small rifle primers.Maybe we can't make a universal 357 silencer that will work on a G19 and handle this kind of pressure and powder charges in a 10' fixed barrel, but if it could handle a 357 MAG. It may be able to handle the big ass cast bullets loaded to SUBSONIC velocities in the longer case so the grease grooves are covered.I highly doubt the pressures would be anything CLOSE to the MAXIMUM. But if it could handle it.
Will A 357 Max 1-16 Twist Stabilize A 180 Gr Bullet Ballistic Chart
That would be pure BONUS. Maybe a triad would help to tame the initial blast and if the fist baffle was inconel it would work. It only really needs to be full auto rated in 9mm. The MAXIMUM would be in much slower firing firearms with longer barrels.The maximum is chambered in single shot pistols and a few lever rifles and the handi rifle. So a 16' -14' barrel at the shortest may be the minimum barrel length the MAX with full power loads would be allowed in with this silencer.I hope quickload has some data. I have not played with it yet.
We also need to find out what rate of twist the 'Whisper-MAX' version would need to stabilize the 300 gr RIE bullet + 282 gr as well as those 2 would be the longest. Once we get the twist figured out for that.Then getting someone to make contender/encore barrels for the subsonic usage is next. Then it's just a few days at the range to whip up some subsonic loads. Then with that figuring out the pressures would be easy. (maybe quickload or some other program could do it.Hopefully the stock 357 twists would stabilize up to the 180 gr and maybe the 200 gr pistol bullets.The 357 Herrett is 44,000 CUP and the 357 MAX is 40,000 CUPThe heavy full power loads made me wish I had a muzzle brake or had a silencer.
That thing is a handful.It's late. And I have a family emergency to deal with this week. Dave,I just ran some #'s for fun.1:14 twist super 14 barrel 358 MAXimum. Shooting Hornady #3520 358 250 gr spirepoint 1.302' long at 980 FPS has a stability factor of 1.448 (in the green)Quickload: 4.8 gr of unique = chamber pressure of 34951 psi (40K psi = max pressure) It gets a velocity in the super 14 of 984 FPS But as I predicted the MUZZLE Pressure has dropped to only 992 PSIBetter load:5 gr of unique = PMAX of 37816 psi, 1007 FPS, and a MP of only 1025 psi The stability is now 1.462 Same load in a 10' barrel has 970 fps and a muzzle pressure of 1568 psi.
Well under that of a 4' 9mmOK, for comparison a 147 gr 9mm loaded with 4.3 gr of unique has a vel of 1010 FPS a PMAX of 31845 psi and a 4' barrel Muzzle pressure of 4285 psiLet's get it down to 990 fps with 4.2 gr unique vel of 990 a Pmax of 30178 and a Muzzle pressure of 4198. Still much higher than a subsonic load in a 357 maximum with a 250 gr bullet.The question: is a stability factor of 1.462 OK? The Miller stability factor 1.3-2 = good FYI the US military uses 1.5 as a guide ( A Storm lake 9 mm is a 1:16 and has a stability factor of 3.923 with a 147 gr factory loads)If I bump the velocity up to 1020 the stability goes up to 1.468 with a 1:14 twist. Now if we could get a 1:12 that gets it up to 1.916 even at 900 fps. I would like a 1:10 That gets up to a 2.76 stability factor.OR Hornady makes a RN 250 gr bullet #3525 which is 1.1' and would have a stability factor of 2.352 at 1000 fps in a 1:14. So that should work.The 250 gr load in the 357 maximum with 5 gr of unique with a 5' barrel would have a Muzzle pressure of 3845 psi about the same as the 9mm. I would not use it on a barrel shorter than 5'.I would like a 10' for more uniform ballistics balance etc.But I believe even NOW we can shoot the 357 MAX subsonic big bullets safely in the current 9mm cans.
To shoot the longer heavier cast bullets we would need a faster twist. 1:12 or even a 1:10 and naturally woudl need a take apart can.