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Dans Club
December 7, 2020
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I bought some .357 Maximum reloaded ammo at an estate sale specifically for the 740. (Reloads have all reload info on labeled boxes). The first 12 rounds, the gun worked fine. After that, the cylinder jammed and would not eject from the frame. It took considerable hitting with palm of hand to eject cylinder. I ejected spent/unspent cartridges. Loaded another six. Fired once and jammed again. Eventually got cylinder to eject and loaded with 38S and fired 12 rounds fine. No problems. So, I reloaded the Maximum loads. Same Problem: Fired once and jammed again. Visually inspected the gun is dirty. I suppose that could be the cause as the gapped is 0.002", but the 38s fired afterwards. Waiting on owner to find wrench and gapper so I can disassemble and clean. He would prefer that I just send it to Bob @ DWCZ. Anyone else have such an issue with the Model 40/740? Suggested things to look for? Alternate troubleshooting procedures? Solutions? I do not want to bother Bob just yet. Thanks for any assistance/ideas.
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Dans Club
March 25, 2013
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The reloads were probably the problem. Maybe to much powder but the cases can back out and block the cylinder from opening. Take a thin screwdriver and push the cases back into the chamber to open the cylinder. Don't pound on the ejector rod if the cases are stuck. A pencil works fine but don't pound on a sharpened one. Lol.
Dans Club
December 5, 2008
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I would suspect the reloads. This is why Most folks will not use reloads from an unknown source, or ones they did not personally load.
Did the primers back out of the casings. This could jam the cylinder. Could also indicate over pressure condition.
Could be a combination of things. If the front of the cylinder and/or rear of the barrel are loaded up with powder residue, the close tolerance of the supermag could obstruct the cylinder. It could happen pretty fast depending on the type of powder and load pressure, etc.
If cleaning the front of the cylinder and rear of the barrel cures the problem then you know there is nothing wrong with the gun. I would be suspicious of the rounds.
August 8, 2016
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snake-eye said
I would suspect the reloads. This is why Most folks will not use reloads from an unknown source, or ones they did not personally load.
Yup!
Dans Club
February 24, 2013
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snake-eye said
I would suspect the reloads. This is why Most folks will not use reloads from an unknown source, or ones they did not personally load.
Agreed!
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Dans Club
February 22, 2009
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.002 is a little tight for SMs. Could be it heated up and closed the gap....
Technically, the glass is always full; half liquid, half air....
Dans Club
December 7, 2020
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Thanks Everyone!
Going to clean and shoot 6-12 Remington Factory Loads through it tonight. What threw me off was that it had no problem with the 38s after jamming twice on the max reloads.
Dans Club
December 7, 2020
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Scout728 said
Thanks Everyone!Going to clean and shoot 6-12 Remington Factory Loads through it tonight. What threw me off was that it had no problem with the 38s after jamming twice on the max reloads.
FOLLOWUP: Cleaned it, but could not remove barrel....(Tool has broken plastic). The gauge (0.002) seemed to fit fine with cylinder fully rotated. Using only factory Remington 357 Max ammo, STILL same problem: ( Fired once and jammed. I got cylinder to eject and loaded with 38S. Same Problem. I was able to manually assist the cylinder to fire the other 5 38s. After ejecting, what appears to be metal-on-metal contact between the cylinder and lower half of the barrel. Are there bushings that would affect alignment? Does something sound bent? Of is it merely a gapping issue? Sounds like it's a "Bob" issue, but would like to get some opinions first. Owner from the start has wanted it sent to DW for repair on my dime. And will do it if not a simple fix. Thanks
Dans Club
February 24, 2013
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Maybe have a gunsmith do a cylinder-to-bore alignment check? Sounds like the bullets are being shaved as they enter the bore and those thin shavings are getting jammed between the cylinder and bore causing the jamming problem. The metal you see is maybe the bullet jacketing shaved/peeled off the bullet?
DWF Supporters
July 12, 2020
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Had that happen on mine, completely stripped the jacket off the lead!! The slug left the barrel tho, but the jacket jammed the whole works up. There was to much free play in the lock-up, the side cover bolts were LOOSE, I tightened them and no more problems. Empty the cylinder and then empty it again, cock the hammer and then put a flashlight(any concentrated light source) at the top rear of the cylinder, look down the barrel to check alignment of barrel to cylinder. If it's off see if the cylinder will rotate some to put it in lock up. If it moves it is in the timing, if not something is misaligned.
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Dans Club
February 22, 2009
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It's a gapping issue, most likely. Not all cylinders are faced well and there tends to be a "proud" area of the cylinder, particularly in the Monson era guns. Set the gap to .004-.006" on the proudest chamber and that should do it. I had a model 8-2 that was finicky on brass; the cartridge rims on some would ride too tight against the recoil shield and jam the rotation. So, the problem could be at either end of the cylinder.
Technically, the glass is always full; half liquid, half air....
Dans Club
January 17, 2015
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I agree with Ron, that the barrel needs a larger gap. I will add though - I do not shoot any .38 out of guns as then the cylinder has residue in it from the shorter rounds, making it difficult to eject .357 rounds. I would clean the cylinder well with a brass brush on a drill and get out the residual powder anytime you shoot .38
Dans Club
December 7, 2020
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Update: Gapped larger than 0.002. Took to the range. Fired one shot. Jammed. Took out the gauge, and the barrel clearance is fine. Took out my light and and it looked like the ejector star might be partially ejected. Range owner took a look and says it looks like firing pin is lodged in primer. Has anyone experienced this before?
It's going to Bob.
October 17, 2017
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Yes, I have experienced the firing pin sticking in the primer. The heavier the load the more likely it can happen because the primer will divot and grab onto the pin. You can remove the pin and give it a good polishing (particularly at the shoulder of the pin) and that should take care of the problem.
Dans Club
December 5, 2008
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3ric said
Yes, I have experienced the firing pin sticking in the primer. The heavier the load the more likely it can happen because the primer will divot and grab onto the pin. You can remove the pin and give it a good polishing (particularly at the shoulder of the pin) and that should take care of the problem.
Good to know! Thanks.
Dans Club
December 7, 2020
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3ric said
Yes, I have experienced the firing pin sticking in the primer. The heavier the load the more likely it can happen because the primer will divot and grab onto the pin. You can remove the pin and give it a good polishing (particularly at the shoulder of the pin) and that should take care of the problem.
Thank You! Experience and knowledge like this is why I will always be a supporter and member. It's still going to Bob for an overhaul.
FYI: The machine for slotting barrel shrouds will be available in 2-3 months. I will be returning one for that service and ordering 2 additional BAs. I marked my calendar, and my phone for May 9th....(although 3 months would be mid-June) to call and place orders.
Dans Club
February 24, 2013
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Is that also when 740 BAs will be ready? Bob told me several weeks ago 740 stuff will be ready in not to distant future.
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Dans Club
March 25, 2013
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I am sure this is not the problem, but, when you slide the shim in to set the cylinder gap do not force it in. It should slide in easily. If it is too tight and you force it in it pushes the cylinder to the rear and pushes the spring loaded dedent ball back. When you withdraw the shim the cylinder springs forward, closing what you thought was a .002 or .006 gap. Try that before you go to the trouble and expense of sending the gun to Norwich.
Dans Club
December 7, 2020
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New Gun......445. Old Problem.
Fired 44 mags all day when received. No Problem.
Loaded new Starline .445 Brass. Experienced reloader was present and checked my work.
Third shot, Firing Pin sticks in Primer cap locking up the cylinder. Soaked in Kroil 24 hrs. Made a 90 degree 0.006" hooked pick.....(see Bad day at range posting) to jiggle between spent cartridge and pin. Cylinder opens. Clean and scrub cylinder bores. Set gap to .006, add drops of Kroil around firing pin for 24 hrs. Use air compressor to blow out excess Kroil through grip tang. Go to range. Fifth shot and pin is stuck again.
Because I used that flatten pick to between spent cartridge and pin, I cannot determine if primer backed out of cartidge?
Because of the Kroil and compressed air to blow around firing pin, I would hope that dirty parts are not causing the hangup.
What about the Firing Pin Spring? Nowhere in the thread has anyone suggested spring failure on the previous gun? And since I sent it to Bob @ DW, I never got an explanation of failure on the 740.
What am I missing?
Sending it to Keith @ DW is not an option I want to resort to, due to anticipated backlog. Local gunsmith is 50% of fixing my problems that first visit.
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