.357 Magnum 158 grain XTP load questions

[KASarich]

OK guys, here is my question:

I loaded about 75 cartridges last night, .357 Magnum, 158 grain XTP with 6.3 grains of Autocomp (a little slower than HP-38). I seated the bullets so the cartridge OAL would be 1.580'' with a light crimp. However, since I was using mixed brass, as I measured all of the cartridges, some have an OAL shorter than 1.580''. A few were even as short as 1.570''.

My Lee reloading manual states 1.580'' min. OAL and a starting charge of 6.2 grains of Autocomp (7.0 grains max charge). My Hornady manual does not list Autocomp for this application, but it does state a min. OAL of 1.590''.

What do you guys think? Would you fire the short cartridges or should I set them aside and pull the bullets? I am firing a S&W Model 65-1 (4'' Barrel). I ask becasue I enjoy having hands, and I enjoy my Model 65 almost as much.

Thanks,
Kyle

 

[358156hp]

You're fine. You have a relatively light load, and the only sensitivity revolvers really have to OAL is if you seat the bullets too long to fit in the cylinder, which wouldn't allow the cylinder to rotate. As long as you're crimping in the bullets cannelure, you're in good shape. You probably have a few short cases, and it's nothing to worry about under normal circumstances. It is very uncommon to find revolver cases that are exactly within "book" length specs. Most handgun cases are actually a bit on the short side. Like yours.

 

[forestswin]

Kyle
A few points.
I've been reloading for a S&W 686 357 for a little over a year now. In that time loaded and shot about 2000 rounds of 357. So I am not an expert, but have learned some this past year. Some other guys here will come along and give some advice to the other points.

First, when starting out with a new load, I usually only make up 6 rounds and test them before going into production. So any mistakes on a few aren't that big of a deal to pull.

Second, XTP's have cannelures. Seat the bullet to and crimp at the cannelure.

Third, I don't know anything about AUTOCOMP - but I thought it was more for semi-auto's.

Fourth, fired brass, especially mixed brass will have different lengths. Measure the cases before loading them. Either trim them to the "trim length" or sort your brass by length. Set your dies up for that length. Different length cases, will seat bullets differently. See CASE LENGTH MEASUREMENT and CASE TRIMMING in your books.

Be safe, become a student of this stuff - its very rewarding and have fun.

 

[KASarich]

Yeah, AutoComp is made mostly for autoloaders, especially compensated guns as it generates a decent amount of gas. I load mostly for .380ACP, 9x19 and .45ACP, and have had OK results with it in .45ACP (although, it can be a bit snappy). It was one of those powders I bought just to try out. I prefer HP38 for those calibers though. I went out looking for some Accurate No.7 last night, but powder is a bit hard to come by these days.

Since I want to shoot the Model 65 this weekend, I decided I would go with the AutoComp since it is a bit slower than the HP38, although not the ideal powder for the .357 Magnum.

The bullets are all seated to the cannalure with a light crimp using a Lee factory crimp die. I just want to be sure that I am not going to generate unsafe pressures with these cartridges.

Thank you for the advice. I have not been loading for that long, maybe almost a year, and I learn more and more about it every day. It has become almost as fun as shooting for me.

 

[Rule3]

Hodgdon lists the bullet and Autocomp. You will not get the COAL when using a bullet with a cannelure (crimp groove) as the tested cases have a trimmed to length which is a tad shorter than what a non trimmed case is. So as mentioned just seat to the cannelure roll crimp and you are good to go.

I have a lot of AC powder use it in both revolvers and semi autos it was supposed to be for compensated guns. I bought it when I could not find HP 38/W 231 as it is pretty close to what I can use it for.

I "never" measure revolver rounds that have a cannelure.

Cartridge Loads - Hodgdon Reloading Data Center - data.hodgdon.com

 

[Cdog]

My two cents, a healthy roll crimp is a good thing for any revolver I load for.

I'm not familiar with your combo, but any round is capable of shooting loose and creating a stoppage.

 

[Nevada Ed]

Many sort their brass by length and lots or brand names ............some times by the number of times shot when the same type, to try for better accuracy.

Hornady xtp is a fine bullet but the cannure is not always in the same place on 1 in 600 or more. Usually there is a wide enough grove so your crimp is some where in the grove and will work, just stop if you feel more pressure than normal when crimping and see what is going on.
This can happen with any brand of bullets with a Cann, so a quick visual or inspection for flaws is a good thing.............
did I mention wrong diameter bullets?

For SD or hunting loads I check the brass and bullets to make sure they are perfect, before loading.

Stay safe.

 

[Granddad]

If it were me, I would shoot away. I've used AC in my 357 loads and it is satisfactory and delivered good accuracy with 125 JHPs. The thing I noticed is that the barrel of my M27 seemed to heat up more and more quickly than it does with other powders of a similar burn rate.

 

[GP100man]

6.2 grs. only makes 25,700psi at starting loads & 1 tenth more & .020" shorter "mite" make it to 30,000 but doubtful as max is 7 gr.

Kinda narrow operating band , but ya done rite by starting at "start"
Ya got wiggle room.

I may try some AC as pressures are alot lower ,with only 100 fps velocity loss compard to WW231/HP38.

Looks to be a lead "friendly" powder .

 

[KASarich]

So, I fired the cartridges today at the range, and they felt like .38 Specials. The accuracy was not bad, though. They defiently went where they should have, but they were definetly not up to .357 Magnum power. I know now that can up the charge a bit.

Aside from that, the AutoComp seemed to work out OK for now, but I will be trying some Accurarte No. 7 once it comes back in stock.

Thank you all for the words of wisdom.

 

[forestswin]

KAS

great - thats the best way to "pull" the bullets

If you haven't tried 2400 and get a chance
I just tried it - works great in my 686

see this previous post I made last week about 2400

pics of target results at the end

http://smith-wessonforum.com/reloading/312607-whats-up-2400-a.html

 

[87hurricane]

I "never" measure revolver rounds that have a cannelure.

This. Revolver bullets with a crimp groove or cannulure are set at this point. I usually find that this puts the round near the listed OAL, but if not it doesn't concern me. As long as the rounds fit in the cylinder, they are GTG.