S/W 337 Jacketed restrictions

[Blue Duck357]

On the S/W website the picture of the 337 Kit gun clearly shows on the barrel "38 S/W Special +P Jacketed". Does this mean that only the heavy lead 38 +P loads can't be fired from it or that only jacketed bullets of any type can be fired from it?

Also curious as to why the 360 Kit gun doesn't have the same warning???

 

[Clemson]

It means that S&W recommends against firing Plus P lead cartridges from Airlites. Standard velocity lead loads are OK. Jacketted Plus P loads are OK. The reason is the propensity of the guns to pull the bullets from the sharp recoil. Lead Plus P loads are typically not crimped strongly enough to resist the bullet-pull force.

I can't comment on the 360 question as I have not owned one. I do own one of the Airlite .38's, and I have not had problems finding ammunition for it. I carry 125 grain jacketted plus P's in mine.

 

[wholehog]

Greetings to all. I've lurked here for quite a while, but here's a thread I think I can contribute to.

I bought a 337 about three years ago and have been pretty pleased with it. In that time I've put about 1200 rounds through it, mostly 125 g JHP +Ps, but also several hundred 158 g LSWC +Ps, both factory and my own reloads, and I think the bullet jump problem may be a little over exaggerated. Using WW ammunition and leaving one round in the cylinder repeatedly while I fire the other four rounds, it takes 12-20 rounds before I can see any noticible movement of the bullet. And that's nowhere near far enough out to bind the cylinder. Using my own +P reloads with a hard cast 158 g SWC, it takes even more rounds. So, I'm becoming comfortable with the idea of carrying the factory load in the gun. The recoil is stout, but it's not THAT bad.

Here's an interesting observation - if I put a LSWC in the chamber and fire 125 g JHP +Ps in the others, it only take 4-8 rounds before the lead bullet moves. So which one has the worse recoil?

Scott

 

[Clemson]

Good point on the recoil, Scott. I read a review of a Scandium 7-shot .357 in the latest American Rifleman last night. Apparently those guns have included instructions for the owner to test bullet pull before choosing loads, just as you did. Jacketted bullets offer less propensity to deform when loaded with the same crimp as lead bullet loads. There are probably some lead Plus P loads that are fine for the lightweight guns. I have never had a bullet pull problem with the 125 grain jacketted Plus P's that I use.

 

[wholehog]

I've never had a bullet pull problem with the 125s either, but based on what I've read, I'd like to use the FBI load.

What might be the ramifications of putting a little more crimp on the factory load? I've tried that already and it seems to make a difference, but hesitate to do it to rounds that I might actually carry.

Scott

 

[KenF]

I did have a bullet pull on my 342PD. The ammo was Sellier & Bellot LRN. Can't remember the bullet weight, but it was not +P ammunition. It was the 5th bullet, and far enough to prevent cylinder rotation.

Maybe this was just a fluke, but I have only used jacketed since.

Ken.

 

[Clemson]

It is probably good for all of us to keep in perspective that bullet pulls have been a fact of life for revolver shooters for a long time, and they are not restricted to lightweight guns. Pulled bullets have tied up many a K-frame over the years -- ask any old-time cop! That said, most modern ammunition loaded by the big companies is remarkably uniform in its crimp and all other characteristics too. These lightweight wonders put an extra dimension on having good, reliable, consistent ammo that you can trust. You guys who test your ammunition before you carry it are doing a very sensible thing.

Much has been written about the effectiveness of the 158 grain SWCHP "FBI Load," but any modern jacketted hollowpoint load will likely be very effective when you have to use it. Since those loads are less apt to tie up the gun than the lead loads, I think their use is advisable, but that is a choice for the shooter to make. Again, testing in your gun, with your grip, etc., is the only way to be certain that you won't have a problem.