I've recently started loading for 357 Magnum. I'm using Lee dies. I am consistently buckeling the case when I seat the bullet -- but only with Remington brass. About midway down the body of the case, a ridge forms around the case, expanding until it is constricted by the die.

It's not that I have the crimp set too aggressively, because I backed the die out until it wasn't touching the case at all, and it still happened. I had the same problem with two different bullets, though they were both 180 grain. It isn't a problem with having too much powder in the case, as we tried it with a very low volume charge.

It doesn't happen with the Starline brass we've been using. We had a stray piece of Winchester brass, and it didn't do it with that. This Remington brass all came from factory ammo, cleaned up in the tumbler, but haven't done anything special to it. However, I can't believe that Remington brass can't stand up to having even a long bullet seated in it.

I can only assume that I'm doing something wrong here, but I don't know what.

A thought to check: If you have a micrometer check the inside and outside radius of the mouth and compare to your others, it may just be thicker brass. If it is use a neck reamer to reduce the inside diameter.

Since you said you are using a 180 gr. bullet, that is long for the caliber. Hold a bullet next to your case, if the "buckling" is at the base of the case you have found the problem, the bullet is extending into the thicker area of the case and just expanding it. Since this only happens with one brand it's a good bet that's the problem. Can't do anything about it except use other brass or a shorter (ighter) bullet. I'll bet that if you use a 158 gr. bullet the "buckling" disappears, even with the Remington brass.

Be sure you're applying a slight flare to the case mouth prior to bullet seating.

You say you've backed the die out 'til the crimp taper isn't in contact with the case mouth. Take this to mean only the bullet seater protrudes down enough for seating the bullet. Only thing I can think of is to make sure you're full length resizing the case.

That almost looks like the bulge from the base of the bullet - Maybe the brass is sized a bit too small making the bulge more apparent. I would try running them through a Lee Factory crimp die and see if the post-crimp sizing ring show resistance at that point.

Alk8944 is right on the money here. All cases have some degree of taper on the inside before you get to the web..some start earlier than others. You wouldn't have seen this problem with a 158gr bullet, or some 180's that leave more of the bullet outside the case(like the Remington 180gr), but the portion of the bullet behind the cannelure is too long for the brass you are using.

If you don't want to give up on the brass you could seat the bullets out to the end of your cylinder, with a margin for functionality, and crimp them with a Lee FCD and try it that way unless you are using a revolver with a shorter cylinder.

Hold a bullet next to your case, if the "buckling" is at the base of the case you have found the problem, the bullet is extending into the thicker area of the case and just expanding it. I'll bet that if you use a 158 gr. bullet the "buckling" disappears, even with the Remington brass.I agree! It doesn't look like the case is "buckling" but it does look like it's bulging. Like Alk8944 suggests, try a 158 gr. bullet or find a thinner case.

Thanks for the diagnosis, guys. I tried a couple different 158 grain bullets in the Remington brass, and it seated just fine. I guess I have to remember from now on to not use that brass with those bullets.

I hate to go against the the trend, but some of thos cases do look buckeled, especially those on the left. It looks to me as though your crimp could be a bit heavy for a jacketed bullet. Just for kicks, back of on the crimp, and see if you still see the problem.

Do the rounds chamber in the gun ok? If they do then it not really a problem. If they dont then a Lee factory crimp die will straighten them out. It looks like the Rem brass is a little thicker and the bullet is not seating straight. This may or may not effect accuracy.

Do the rounds chamber in the gun ok? If they do then it not really a problem. If they dont then a Lee factory crimp die will straighten them out. It looks like the Rem brass is a little thicker and the bullet is not seating straight. This may or may not effect accuracy.

No, we tried that and they definately didn't fit into the cylinder.

:) Howdy I finally decided to register and share my 2 cents worth. After looking at the pictures of the cases, and with out being able to handle them, it appears from the picture that the brass migh be a fuzz long and with the crimp set as it is showing in the picture that will indeed buckle a 357 case. Try screwing the main part of the seating die out even further than you have, seat your bullets to length and follow the good advice given ealier and use a Lee factory crimp die. I own one for every handgun caliber. Good luck....

sam

:D

I've recently started loading for 357 Magnum. I'm using Lee dies. I am consistently buckeling the case when I seat the bullet -- but only with Remington brass. About midway down the body of the case, a ridge forms around the case, expanding until it is constricted by the die.

It's not that I have the crimp set too aggressively, because I backed the die out until it wasn't touching the case at all, and it still happened. I had the same problem with two different bullets, though they were both 180 grain. It isn't a problem with having too much powder in the case, as we tried it with a very low volume charge.

It doesn't happen with the Starline brass we've been using. We had a stray piece of Winchester brass, and it didn't do it with that. This Remington brass all came from factory ammo, cleaned up in the tumbler, but haven't done anything special to it. However, I can't believe that Remington brass can't stand up to having even a long bullet seated in it.

I can only assume that I'm doing something wrong here, but I don't know what.


I had the same thing happen to me. My plan is to make sure the bullet is started straight as possible.

I hate to go against the the trend, but some of thos cases do look buckeled, especially those on the left. It looks to me as though your crimp could be a bit heavy for a jacketed bullet. Just for kicks, back of on the crimp, and see if you still see the problem.


If you read his first thread, he already tried backing off of the crimp.

Heres what he said....
It's not that I have the crimp set too aggressively, because I backed the die out until it wasn't touching the case at all, and it still happened. I had the same problem with two different bullets, though they were both 180 grain. It isn't a problem with having too much powder in the case, as we tried it with a very low volume charge