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Post by bradshaw on Apr 18, 2013 12:18:20 GMT -5
ChargerFan.... The Dan Wesson M40 .357 Super Mag is by far the most efficient of the Maximum or Super Mag cartridges in the Big Dan. Primarily due to endshake on the swingout cylinder, the DW cannot achieve Ruger velocites.
Continues to amaze me how DWA made such accurate revolvers in that schoolhouse machine shop, with near perfect chamber-to-bore alignment more usual than unusual. The tensioned barrel of itself could not produce famed DW accuracy in the presence of an oversize of crooked forcing cone----no matter how perfect the rest.
David Bradshaw
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Post by bradshaw on May 11, 2020 7:40:01 GMT -5
Quick Draw McGraw.... answering your question on the .357 Maximum here, as the clues are important:
Low velocity, high ES Your chronograph is on the fritz or placed too close to the muzzle. Slow powders produce uniform velocities in the .357 Maximum. Specifically to include powder you’re using with the Hornady 180 XTP----Win 296/H110 and Accurate 1680. Win 296/H110 yields some of the highest velocities but most bullet don’t like it for accuracy. This rule is at variance with great accuracy achieved with 296/H110 in all the magnums and .45 Colt (“Ruger loads”). Your low chronographed velocities suggest air shock or concussive shock is getting out ahead of the bullet to trip the START SCREEN, after which the bullet trips the STOP SCREEN. This increase in time between start & stop translates in chronograph brain to slow velocity. The chronographs reading of shock is inconsistent, which shows up as wide variation ES (Extreme Spread).
Rounds with vary low velocity may also send a shock wave----or smoke----ahead of the bullet. Low velocity is not the problem here.
Increase distance to start screen. If your chronograph wears its brain & screens in the same place, you may need more distance. I’ve never experienced your problem with my Oehler Model 33 and 35P chronographs.
Spitting Sideblast of bullet particles is caused by: * Chamber-to-bore runout (the more, the merrier). * Rough or abrupt chamber LEADE * Rough chamber EXITT HOLES (rough throats). * Rough FORCING CONE. *Tilted or off-axis forcing cone. * Loose BASE PIN.
Of the above list, by far the most likely culprit is chamber-to-bore misalignment (runout). Easiest cure----a cylinder which reduces or eliminates the problem.
Jack Huntington is a wealth of analytic experience; your revolver is headed for able hands.
Handgun Silhouette As for a chance to try out the steel game, check ranges and clubs in your area. Bring ammo, notebook to record all sight dope. If possible, sight-in beforehand @ 50, 100, 150, and 200 meters. Switch to IMR 4227 or Hodgdon 4227 (I use the two interchangeably, and have done so at the highest level of competition), and charge powder to base of bullet. ACCURACY gets you on track. Velocity without accuracy derails the train before it leaves the station. David Bradshaw
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Post by Quick Draw McGraw on May 12, 2020 2:38:29 GMT -5
Bradshaw,
Thanks for the help, this is very enlightening. What's the max pressure for the .357 Maximum? All my load data says 40k PSI. From your earlier post and from what Jack mentioned, it sounds like it could be closer to 60k PSI.
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Post by bradshaw on May 12, 2020 7:33:30 GMT -5
Bradshaw, Thanks for the help, this is very enlightening. What's the max pressure for the .357 Maximum? All my load data says 40k PSI. From your earlier post and from what Jack mentioned, it sounds like it could be closer to 60k PSI. ***** SAAMI member ammo companies dropped chamber pressure for .357 and .44 magnums decades ago. Yet, pressure of a certain rifles loads----which were never associated with older firearms----ratcheted up. For the handloader, jacked pressure is paid for in shortened brass life, etc. Dick Casull’s .454 hit the stands with over-the-top pressure, round-about 65,000 psi. A PROOF load, a.k.a. BLUE PILL (named for the blue dye used to distinguish the load), boosts standard pressure 40%. At around 90,000 PSI, pressure reading becomes erratic. A .454 Casull @ 65,000 PSI... add 26,000 (40%) = 91,000 PSI. The brass case is analogous to the head gasket in an engine. When it lets go, other things happen. Head gasket strength varies between engines and head the gasket material itself. But once it blows, damage ventures forth. It is astounding the pressure some actions withstand, but that should not be a blueprint for FUN. If the objective is VELOCITY, the price may break the bank. I’d love to have 2,000 FPS from a .44 or .45 pistol----with the bark & recoil of a .45 ACP. For all the great powders we have, it ain’t happening. The .357 Maximum intends to boost ballistics of the .357 Magnum without drawing upon .44 Magnum recoil. This was accomplished. The guns get more velocity with heavier bullets @ 40,000 PSI than a .357 Mag. And the .357 Maximum was designed for more. At the same time, the .357 Maximum just happened to find itself a cartridge of high INTRINSIC ACCURACY. Maximum pressure for the .357 Maximum probably hovers in the 60,000 PSI zone, but I would hold maximum OPERATING PRESSURE below that, primarily for the sake of barrel face and brass life, and conservation of SANITY & SHARPSHOOTING. David Bradshaw
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Post by jfs on May 12, 2020 12:00:33 GMT -5
squawberryman.... not sure your exact question on flame cutting. Bill Ruger, Jr., was the first to observe this phenomonon, as he paid very close attention to the guns as I shot them. Ruger, Jr., also did his share of shooting. The high pressure experimental ammo was a ticket to rapidly learning a lot about the revolvers and brass. Bill Ruger, Jr., then noticed that top strap etching or cutting subsided after several hundred or a thousand rounds. He theorized the falloff in erosion a result of flame hardening. The same is not true for forcing cone erosion. BARREL FACE EROSION (a.k.a. forcing cone erosion) continues, and does not abate until well past proper time to reface and set back barrel. David Bradshaw David, My DW 357 Max has slight top strap cutting and I see above that Bill Ruger Jr. believed it stopped due to the metal hardening from cylinder blast. Have you observed this cutting to continue or is B.R.Jr. correct?? I know DW included an extra barrel with their 357 Max for cone erosion and I have two extra barrels so I`am good in that department. The Dan Wesson 357 max is an accurate and sweet shooting DA revolver. Any recommendation for 180gr JHP handloads?? PS- The 180gr Partition was deadly on boar..
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Post by bradshaw on May 12, 2020 12:51:02 GMT -5
James.... the observation by Bill Ruger, Jr., that top strap erosion tapered off rather quickly came early in the shooting of the SRM prototypes----well before the revolver reached production. This information was made available to the firearms press and, for the most part, ignored. As you correctly note, the extra barrel shipped with the DWA M-40 provides the shooter a fresh barrel should the shooter grow alarmed at forcing cone erosion. Dan Wesson Arms already knew that top strap cutting wouldn’t amount to diddley.
The Maximum should keep any balanced bullet on track when loaded with IMR/H4227. The 180 should shoot straight with Accurate 1680 and Accurate 5744. Most bullets don’t like Win 296/H110 for accuracy.
Used Hercules 2400 with the Hornady 158 JHP in experiments. Good accuracy, some excellent accuracy; fastest powder I would use in .357 Maximum and haven’t loaded it in the Maximum since development days. For instance, I wouldn’t let Hercules Blue Dot anywhere near a Maximum of mine, and say the same for Alliant Blue Dot. Won’t touch Lil’Gun.
IMR 4198 is cap[able of extreme accuracy with 200 grain bullets in the .357 Maximum, but must be heavily compressed. BARREL TIME is just too long, no forgiveness. And velocity is soft. Powders between Alliant 2400 and IMR 4198 have burn rates applicable to the .357 Maximum. It’s up to the target to tell us whether an accurate bullet will be accurate with which powder.
Seated over 18.5/H4227, the POWDER COAT Bradshaw-Martin cast 194 SWC GC continues to hold great consistency out to 200 yards. Lee Martin and this shooter have sandbagged other powders @ 100 yards. Since the bullets hangs tight @ 200 yards, bullet stability speaks for itself. ACCURACY vis-a-vis powder is fully resolved @ 100 yards. Vihtavuori N110 is a fine stick powder in the 296/H110 zone. VN 110 is more accurate than similar burn-rate 296/H110, but hasn’t matched IMR 4227 and H4227. (Again, I use the two 4227’s interchangeably.) David Bradshaw
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Post by jfs on May 12, 2020 15:54:33 GMT -5
IMR-4227 has given me good accuracy and H-4227 under a 300gr XTP with 1450fps MV was my 454 "whitetail load" giving me excellent accuracy, penetration on almost any angle shot out to 100 and manageable recoil. I`ll be using the IMR-4227 on my next 357 Max handloads.... 2400 under a 158gr Swift sounds interesting.... Thank`s Davie...... Did anyone ever tell you that you should write a book??
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Post by Quick Draw McGraw on May 13, 2020 6:46:59 GMT -5
It is astounding the pressure some actions withstand, but that should not be a blueprint for FUN. If the objective is VELOCITY, the price may break the bank. I’d love to have 2,000 FPS from a .44 or .45 pistol----with the bark & recoil of a .45 ACP. For all the great powders we have, it ain’t happening. Mr. Bradshaw, I apologize if I gave the wrong impression. I honestly wasn't asking what the pressure ceiling was so I could chase velocity or push the limits. I was just curious to know what the parameters of the cartridge are since (to my knowledge) there are no SAAMI specs for the .357 Maximum. The internet is an untrustworthy source rife with "experts." I figured you would be a far more trustworthy resource given your history with the cartridge. So far, your responses have provided far more detail than I had hoped for. Please rest assured that your experience is being respected and your advice heeded.
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