10% of my 357 sig rounds fail the setback test

[hAkron]

When I load 357 sig I resize first with a .40 die, then with a Lee 357 sig die. I expand just enough to not damage the bullets as I seat them. I seat with a Redding Competition seating die, then I crimp using the Lee FCD, which does a rifle style collet crimp (this isn't true of lee's other handgun caliber FCD's that I'm aware of). I use HS-6 or Bluedot. My charges are not heavy enough to fill the case. I have been using the Berry's 124gr HP bullets because they have a nice long shank on them. When the rounds are completed, I press them into the front of my bench with my thumb and if the bullet moves, the round fails QC and goes into a pile to be torn down and disposed of.

So there is my process. About 10% fail the setback test. I'm not completely sure if the issue is a size variation in the bullets (I love Berry's bullets, but the 124gr HP are not my favorite). Or if some of my 'once fired' brass is just spent and won't hold neck tension any longer (I don't keep track of times fired), or if I'm just pushing too hard on my set back test (I just did 200 yesterday and my thumb hurts still today). Also, I know that hotter loads where the powder more completely fills the case will help mitigate setback, but I don't need super power loads for range work.

I plan to try some different non-nickel plated brass (I got 1300 nickel once fired for super cheap), and maybe go with a different bullet (but it needs to be economical like Berry's). I'm also going to get a bathroom type scale to push against so that my setback tests can be more consistent.

I don't really have a question, just sharing my experience with loading this tricky cartridge.

[abq87120]

I just went through the same thing with 125gr Montana Gold JHP in my Starline 357 Sig cases. Many reloaders use this bullet with absolutely no issues. But I did. A hard coating and slick. I just got my first order of Precision Delta 124gr JHP and am very happy with the improved set back result.

http://precisiondelta.com/detail.php?sku=B-9-124-JHP

I ordered a thou of the 9mm's ($89) and one of 40 S&W FMJ FP's ($126). With the 2k order, the shipping was included in the price. The 9mm bullets will also work in my 9mm gun.

I am using Lee steel dies with an FCD. I test my set back by making a few bullets of a standard COAL, load them into a mag and quickly and vigorously hand-rack them through my gun one time. Measuring these using PD rounds seem to have solved 99.9% of my problems.

I also switched to 13.0g of AA #9 (124gr bullet, 38k psi). This helps prevent set back. For the $23 or so, it was worth it for me to quit fighting my bench and getting out shooting.

Also, there are some who have success with the FCD and a cannelured bullet:

https://www.montanagoldbullet.com/pricelist.html
Search for "125gr. SIG JHP".

If the PD's hadn't worked, those cannelured MG's would have been my next attempt. But they cost $54 more per k ($143/k) than the Pd's. I think that includes shipping also. My gamble ordering the PD's first was that they could be used in my 9mm gun if the Sig thing didn't work.

I did like you and asked advice on several banger forums. I tried all of the advice. 100% of the bullets in my MG JHP experiments displayed significant set back. I finally hand fed them (MG's) in my gun to shoot them up and recover the brass.

I strongly suspect that some (many/most?) of the people offering that advice do not test for set back and are not aware that they are experiencing it.

[moxie]

Sounds like insufficient neck sizing. I'd go with a good .357 full length sizer die, followed by a seater. Two steps. Just like a rifle.

BTW, I agree completely with your "push test." But I don't think a full case will help with setback.

Do you have the sizer die adjusted down enough? A little cam-over?

Are you lubing the cases lightly?

[Brian Pfleuger]

There's no reason that sizing with the one die would be different than sizing with two dies when one of them is the same as would be if you only used the one.

Virtually everyone uses a 40SW carbide die followed by a 357sig die.

The issue may well be TOO MUCH crimp.

Excessively crushing the case mouth, even if it doesn't look like it, will actually bend the neck walls away from the bullet and REDUCE tension. The flaring step can cause the same effect. Use absolutely minimal flare. I use none with some bullets and they seat fine.

Start by trying very little crimp. Keep checking for setback until you find an optimal crimp.

If you can't get it to hold, you can go to the other extreme where it actually crushed a cannelure into the bullet. I've done that and there seems to be no effect on accuracy, at least as well as I can shoot my G33.

Another solution is to use a powder that will result in a compressed charge. AA9, 800x and a couple others are options.

[snuffy]

I don't mess around with two dies. What's so hard about a little lube on the cases? I toss them in my tumbler after they're done loading, takes the lube right off.

I don't however, use an expander or bell on the mouth. I chamfer the inside pretty deeply, that allows the bullet to enter the neck, and insures maximum neck tension. The neck is so short of the 357SIG cases you have to have plenty of grip on the bullet. Then people use 40 S&W cases, necking down 40 cases results in an even shorter neck.

[jepp2]

I get less setback on my reloads than I get with factory loads.

However, I feel the chambering action of firing the round ahead of it is much more accurate test than a static thumb press test. While the thumb test can give you a estimate of adequate neck tension, nothing replicates the action of the round being fired and the subsequent round being chambered.

I don't use an expander at all, I just seat my bullets with care and don't crimp afterwards. I use the Montana Gold FMJ bullet.

I size to headspace off the shoulder, so I have a shorter neck length than many loaders who size more of the neck.

[hAkron]

Does anybody know the correct amount of pressure to apply for a good push test? Part of the problem could be too much leverage where I hit a good spot on the bench, and get a solid push resulting in a greater force than would normally be applied in a real world setting.

[Brian Pfleuger]

I've read that it should be 40 pounds but it doesn't really matter.

A much better test is to cycle them through your gun 4 or 5 times and see how much setback you get. A few thousandths isn't going to hurt anything.

Actually firing the gun and checking the following chambered round would be the next step.

As long as they make it through a couple of actual, live fire chamberings, nothing else matters, unless you intend to run them through your gun repeatedly for some reason.

[SL1]

I have read (but not yet tied to measure) that cleaning the inside of the necks will provide a better grip on the bullet.

Also, there are some brass that have thinner walls than others. You did not say if the ones that fail your test are different headstamps than the ones that pass.

SL1

[Dave P]

Lee crimp die solved all those problems for me. Now it is a simple caliber for reload for.

[Sportster]

I use a Corbin cannelure tool. It's a hand cranked deal. You put a bullet in it with a set length measured, push it in against that and then put the handle down on top of the bullet and turn a crank, I do it two revolutions, and it puts a cannelure in the bullet about where it is seated in the neck. Makes a IIIIIIIIIII mark around the circumference of the bullet which helps hold the bullet in when it seats. Keeps it from moving. I use the standard Lee sizing die on my Dillon 650 with a touch of resize spray, making SURE I do not get any sizing inside the necks! I turn them away from the spray and only spritz a tiny amount, rotate the casings and another tiny spray. Just enough to get the cases a little wet. Let em dry and go at it. I cannelure the bullets beforehand, however many I'm reloading. I only open the neck a tiny amount, enough to not get a crushed neck or have the bullet sliced down the side when seating. Has worked great for me. I also do a push test on my rounds on the edge of the bench. I don't go crazy though. I push on it enough. If it don't move or very little, good to go.