645 still jamming

[HarryH]

Hi, I'm still having problems with my Model 645 jamming. First of all my case overall length is 1.210 inches, with Lyman's 200 grain semiwadcutter 452460.

All of the jams were the new cartridge being stripped from the magazine, but then are cockeyed and not entering the chamber. I had replaced the recoil spring with a "factory spec" one from Wolff springs.

When I load the magazines, I am always careful to make sure the cartridges are fully to the rear of the magazine. I notice that when handling the loaded magazines off the gun, that if I push the top cartridge forward off the magazine, the next cartridge in the magazine has slid forward some. I wonder if that is what is causing the jamming.

I have attached 2 photos showing the cartridge having slid forward, and what it looks like after loading the magazine. Are the cartridges in the correct position?

I have 5 magazines that all do this. Do I need to adjust the lips on the magazines?

 

[Tazman11]

Have you tried shooting a box of good factory ball ammo through the gun. I would doubt your problem is how you load the magazines. If the ball ammo doesn’t for well, you might need to polish the feed ramp or chamber. How many rounds did you shoot through the gun before ou had the problem? Did the problem start with this ammo. I doubt the pistol was designed with Wadcutters in mind!

 

[Sevens]

I have loaded a LOT of cast lead 200gr LSWC but I have always stuck to the classic H&G68 style.

When I load them, the front driving band is much lower in the case, so that it only slightly protrudes.

Does your 645 run and feed properly with ball ammo?

Do these handloads you show run and feed in any other .45’s?

I see these pictures and I think I’d want that bullet seated deeper in the case — however, I have never worked with this bullet.

 

[Yendor357]

Harry, take what follows with a grain of salt, but think about it.

I have long ago abandoned using cast bullets in S&W autos. I used a Lyman SWC that looked a bit different than yours. It was rare, but occasionally, I’d get a failure to feed. I wasn’t shooting matches nor self defense, so the rare stoppage was acceptable.

The reason I quit shooting cast thru S&W 45 autos is because I could never get the cast bullets to group as well as a Nosler 185 or a 200 XTP. I know that blasphemy to say a Smith doesn’t shoot cast well, but I only know what I see. It took me a long time for that to sink in my thick skull because cast bullets and Smith revolvers work so very well.
I just no longer get that occasional unexplained flyer with a jacketed bullet in a Smith 45 auto. I have 4 of them.

I switched to running nothing but jacketed bullets thru my Smiths, and the aggravation has gone way down.
Another weirdness is, a couple of my guns don’t settle down until after 15 rounds go down range after cleaning. If you disagree with everything I’ve said, I don’t blame you. But like I said, all I know is what I see.

* I prefer the grip of the 645/745 even tho the 4506 is supposed to be better. The 4506 digs into my middle finger. Where as the smooth, rounded 645/745 are much more comfy. I like all my Smith 45s. But they’re fussy.

 

[stansdds]

What is the condition of the magazine spring, new or well used? A weak magazine spring can induce feed issues. Also, I see an orange magazine follower. This was the second design by S&W and replaced the troublesome metal follower, but the black follower was the last design and considered to be the best magazine follower.

 

[Frank Black]

First of all, if ALL your mags do this - and they’re all properly sprung with Wolff springs - you don’t have a mag problem. You’ve got a gun problem.

Something’s going on at the feed ramp, in the chamber, or it's a breech-face issue possibly with the extractor going wonky.

If it were me, I’d try contacting BMCM on this board for suggestions on the indicated fix, or possibly to set up shipping him your M645 for him to fix.

Another S&W member that's a wiz at fixing issues is Guzzitaco.

 

[WR Moore]

I'll jump on the "too much shoulder" sticking out of the case band wagon. Factory chamber leades aren't designed for that type of bullet. You might first try loading some dummy rounds with a shorter OAL to see what works. Also, that the magazine springs might need replaced. The next cartridge to feed sliding somewhat forward isn't uncommon, generally doesn't interfere with function. But, if you can find the latest & greatest followers it might help. The little dimple in the floor plate of the 1991 original mags was intended to provide friction to keep the last round in place for proper feeding.

 

[ACEd]

First I have heard of feed issues on earlier 645 pistols - thought they began with the early 4506/4516 pistols but then I am coming late to the party. Did the 45 feed issues predate the 4506/4516? Do you have the same problem with factory manufactured jacketed ammunition?
As to the late 4506/4516 black follower, be aware that changing the follower may or may not have any significant effect. There were multiple changes to the 4506/4516 pistol as well as the magazine top feed lip metal geometry to address the 4506/4516 feed problems.
I am assuming all your mags are the original metal base orange follower 645 mags (with good mag springs). Rather than just changing the follower, you might want to get a late 4506 plastic base black follower mag and try that.

 

[Tom S.]

When I load them, the front driving band is much lower in the case, so that it only slightly protrudes.

This!!! I shoot SWC in 45 and the front band is either flush with the case or as Sevens said, just barely protrudes.

 

[Rule3]

SWC are very picky about overall length and how much of the driving band is exposed out of the case.

A picture of you cartridge would help. Just a thumbnail or hair should be exposed regardless of Specs or case gauges

 

[HarryH]

Hi Thanks everybody for your advice. I'm mulling it all over and will try some more ball ammo and see how it works. What has me snookered is that I have fired many hundreds of rounds with this gun, these reloads, with these bullets. And it never jammed until now. I'm not doing anything different.

 

[mscampbell2734]

Hi Thanks everybody for your advice. I'm mulling it all over and will try some more ball ammo and see how it works. What has me snookered is that I have fired many hundreds of rounds with this gun, these reloads, with these bullets. And it never jammed until now. I'm not doing anything different.

OK if this load has worked before then either something has broken or worn out.

Since you've changed the recoil spring the next thing to look at is the magazine springs. This normally surfaces with the last or next to last round does not feed. These rounds have the least spring tension lifting them.

Have you checked your extractor? The extractor needs to flex outward slightly as the round feeds upward. If your extract is stuck in place the hook could be catching on the cartridge rim.

I'd suggest a detail strip and clean. Shooting cast ammo produces more soot and carbon then factory FMJ. This is a 30 year old plus gun after all.

 

[6string]

I had one of the very first S&W 645s. It was brand new and I was the original owner.
It was very, very reliable.
Cast bullets? No Problem!
I even used the Lyman 452454 255 gr SWC in it with light charges of Bullseye or Unique.

One amazing thing about the 645: It would even reliably cycle (manually) a full magazine of empty cases!

 

[stansdds]

I had one of the very first S&W 645s. It was brand new and I was the original owner.
It was very, very reliable.
Cast bullets? No Problem!
I even used the Lyman 452454 255 gr SWC in it with light charges of Bullseye or Unique.

One amazing thing about the 645: It would even reliably cycle (manually) a full magazine of empty cases!

That was one of the big selling points of the Model 645, it was utterly reliable out of the box.

 

[6string]

That was one of the big selling points of the Model 645, it was utterly reliable out of the box.

Yes.
And, that was something sorely missing with Colt!

 

[Frank Black]

I had one of the very first S&W 645s. It was brand new and I was the original owner.
It was very, very reliable.
Cast bullets? No Problem!
I even used the Lyman 452454 255 gr SWC in it with light charges of Bullseye or Unique.

One amazing thing about the 645: It would even reliably cycle (manually) a full magazine of empty cases!

Yep. I shoot both factory and handloads in mine all the time. It never jam-skis. My 645 is a later model toward the end of the run.

My handload uses a coated 230grn HC boolit (H&G #34 mould) over 4.8grns-5.0grns of Bullseye. So a mid-range ‘ball’ type load.

This load also runs without a hitch in my 4506, 4566, and 1911s.

Obligatory pic:

 

[Exchipy]

Got this 645 at the San Jose gun show, very soon after the model was first introduced. Its barrel was poorly fitted by S&W, very loose and wouldn’t hit worth crap, though I don’t recall any particular reliability problems with this pistol. But, its accuracy issues likely explains why it was being offered at a gun show while still in high demand. Within a year or two, Irv Stone of Bar-Sto started making barrels for 645s, and fitted one to this pistol for me. Over the decades, I’ve made some other alterations to it, as you can see:


It is easily one of my best shooting .45ACP pistols, two hands standing at 50 feet. The 200gr. LSWC load I used to make this target was a popular choice for 50 yards among the top Bullseye competitors during the ‘40s, ‘50s and ‘60s, obviously because it is so easy to shoot and gets the hits.

 

[surfgun]

Both my 645’s will chamber empty/ spent brass.

 

[Fastbolt]

Just started to exhibit issues?

If it were mine ... presuming I knew for a fact that the bullets and load were the same as those previously successfully used ...

I would replace the recoil and mag springs. If I were shooting 'target loads', I use the lighter spring originally sold by S&W, or a modern analog).



To really maximize the potential for resolving the problem, I'd replace the original 645 mags with the newest 8rd version, with the plastic follower and butt plate, and the impressed "P-Lips" on each side of the mag lips.

The original 645 mags didn't exert a lot of pressure to secure the top round from being displaced under recoil. Matter of fact, one of the early complaints you could hear with the 645 mags was that when carried in a mag carrier (upside down), the accumulated impact force of walking or running could allow the top round to be dislodged from the feed lips. A symptom was when someone pulled out a spare mag from their carrier, and the top round had shifted forward and was barely held by the lips.

Just some thoughts.

 

[HarryH]

<<Have you checked your extractor? The extractor needs to flex outward slightly as the round feeds upward. If your extract is stuck in place the hook could be catching on the cartridge rim.

I'd suggest a detail strip and clean. Shooting cast ammo produces more soot and carbon then factory FMJ. This is a 30 year old plus gun after all.>>

There it is! Thinking about the trip to the range on Friday, I "now" remember that on one of the jams, there was a spent case still inside the action, "floating" on top of the live cartridge that wouldn't chamber. Rather crowded in there.

BINGO!

So it was an extraction problem. So I just checked closely the inside of the extractor and found a load of crud. I had to scrape it out with a very small sharp knife. So I had not cleaned well in there, and from now on I will. The extractor was flexing slightly as it should.

Thanks for the very good advice. This is a good group of people.