SMITH 66/.357 Question

[Wrbjr]

I am loading some rounds for my 66. I have a question....

Hodgdon data sheet calls for Winchester SPM primers. Lee Second Edition lists just small pistol primers for the .357 Magnum. HS6 is the powder ..... what is the issue if I use the small pistol primer instead of the Magnum primer.... any? I am loading just above the start load... I have both primers... just don't understand why Lee does not list the Magnum primer ...? (XTP 125 Grain)

When I load the 158 grain cast boolit....... same situation..... does it matter which primer?

[Ola]

With HS-6 the SP should powerful enough. Only if there is a big velocity variation, try out the SPM.

In .357 mag small rifle primer is also a valid option specially with relatively slow burning powders like H110, VV N110, H4227...

[stubshaft]

I used mag primers in hot loads that used hard to ignite powders like 296. For something like HS6 in a moderate loading I would not hesitate to use regular SP primers. If you want to use mag primers for all of your loads go right ahead, just keep a close eye out for pressure signs when you get near max loadings of some of the faster primers. The mag primer has more brisance and a slightly thicker cup and a slightly higher price tag.

Good Luck!

[Wrbjr]

Thanks guys.... that helps alot. Now the last issue I have is cartridge max and or min length. Still don't have a clear picture on this issue... makes for some nagging doubts.....:veryconfu

[376Steyr]

Cartridge length or case length?

[Wrbjr]

Cartridge length. I have the min COL listed as 1.590 for .357 Magnum... So my mind wanders and wants to know if that is the minimum length that we can use... why not make it a tad longer to be safer. Plenty of room for the cylinder to rotate... so where would most folks seat that bullet ? 1.590.... 1.6...... ? Enquiring minds....

[kyle623]

you can go over on cartridge length, min is listed to keep pressure down. if you go below min COL your pressures could spike.

[Frosty Boolit]

when loading .357 I let the cannelure or crimp groove decide the oa length.

[Wrbjr]

Unfortunately just because the round is crimped within the crimp groove is not necessarily safe. I can make this batch of .357's fall below the "MIN" col and still be within that crimp.

I have decided that the safe number is .010 above the listed min. Any variations will be above the min and no worries.

They shoot well and are accurate and show no signs of excessive pressure... plus I load toward the middle of the load data sheet rather than the hot side.

[fecmech]

Unfortunately just because the round is crimped within the crimp groove is not necessarily safe.
Where are you getting minimum COL for a .357?? So .357's loaded with wadcutters at 1.275 oal are unsafe?? Oal is determined by the bullet used and is different for every bullet. Cast bullet data has different oals for different bullets. Max oal is there only for SAMMI specs and cylinder fit.

[Wrbjr]

I am quoting a specific round... Hornady XTP 125 grain. Min 1.590 col.

[kweidner]

+1 what frosty said if they will fit cylinder. I always crimp to groove in handgun. they fit in my Dan Wesson and model 19.......my contender too but I guess that is a different ballgame.

[fecmech]

I am quoting a specific round... Hornady XTP 125 grain. Min 1.590 col.
I apologize as I did not catch the XTP reference in your first post, I thought you were talking a generic minimum oal for the .357. In regards to the XTP mentioned I would be willing to bet a substantial amount of money that anywhere you crimped in that 125 XTP crimp groove with the recommended load data would be "safe" be it min or max load.

[Wrbjr]

I apologize as I did not catch the XTP reference in your first post, I thought you were talking a generic minimum oal for the .357. In regards to the XTP mentioned I would be willing to bet a substantial amount of money that anywhere you crimped in that 125 XTP crimp groove with the recommended load data would be "safe" be it min or max load.

No apology necessary... I appreciate all input. I think I agree with you about the crimp groove... it would probably just slightly increase pressure and since I don't load to the hot side I am sure it would be ok. The start load for this round is 9.8 grains and the never exceed is 10.9. I have loaded them to 10.5.

My question would probably have been better phrased had I asked about this min col ref the never exceed load.

[376Steyr]

Aha. You are correct in paying attention to the minimum cartridge OAL. Different manufacturers put the cannulure in differing locations on their bullets, even if they are the same weight. A powder charge that is a maximum load with a Brand X bullet may be above maximum with Brand Y, if Brand Y gets seated deeper and thus reduces case capacity.

[Frank V]

I pretty much use standard pistol primers with all my handgun loads with the exception of when using H110 powder.
Frank

[MtGun44]

Understand that the issue for LOA is twofold - first will it fit the mag or cylinder. The
other end is what size the combustion chamber below the base is in your round compared
to the pressure data you are copying. If you have the base in pretty much the same
postion (.010 is WAY plenty accurate enough) then your pressures should be in line
with the published data. Just be aware that if you are making the combustion chamber
volume substantially smaller than the published data, you need to reduce the powder
charge to account for this. This is a stong effect in tiny cases like .380 and 9mm Para,
a bit less in a long case like .357 mag, and a bit less in a huge case like .45-70.

As to the original question, primers are a mostly secondary effect issue, and some powders
definitely do less well with a mag primer than with a std primer (Unique and 2400 for
examples) and some powders seem to need a mag primer to light reliably and burn
fully, esp in low ambient temps (H110/W296 for example). Either can work with the
"wrong" primer, but may have some "issues" - like unburned powder, poor ignition or
fliers, depending.

Bill

[MGySgt]

you are using Hornady J's what does the Hornady manual say about min and max load for you powder selection???

Most of us have many reloading manuals just for this reason. I use Serria - I use their manual, Hornady - I use their's.

But all of the have a minimum and maximum charge weight and they sate start at the min and work up the load. Don't just pick a load somewhere in the middle.

Different lots of brass, different primers, different guns can all make a high end load safe or unsafe!

One last thing - with a J-word bullet with a canalur you are suppose to set the crimp in the middle of the canalur. Keeps the case from bulging when soem grow due to shooting and loading.

Just my 2 cents worth!

[x101airborne]

While not an expert by any standards..... Try em both.

Load 18 rounds with the SP primer and the SPM primer and shoot em. Your gun will tell you and the pressure difference will not be that much. Let your gun do the talking.

[Wrbjr]

While not an expert by any standards..... Try em both.

Load 18 rounds with the SP primer and the SPM primer and shoot em. Your gun will tell you and the pressure difference will not be that much. Let your gun do the talking.

Not a bad idea... heading to the range in the morning to test out a few different loads... may just throw in a few Magnum primers for heck of it.

[Wrbjr]

you are using Hornady J's what does the Hornady manual say about min and max load for you powder selection???

Most of us have many reloading manuals just for this reason. I use Serria - I use their manual, Hornady - I use their's.

But all of the have a minimum and maximum charge weight and they sate start at the min and work up the load. Don't just pick a load somewhere in the middle.

Different lots of brass, different primers, different guns can all make a high end load safe or unsafe!

One last thing - with a J-word bullet with a canalur you are suppose to set the crimp in the middle of the canalur. Keeps the case from bulging when soem grow due to shooting and loading.

Just my 2 cents worth!

I have manuals... but I do not care for the way the powder companies seem to be tied at the hip with a particular round. Alliant only quotes Speer at least as far as I have seen and Hodgdon will quote Hornady. I'm sure they are tied together somewhere but I do not care to be forced into using Hodgdon with Hornady. Or Alliant with Gold Dot. So I do test my loads out... because they seem to be mutually exclusive of each other.

I never load to max specs....

Now this brings up another question that will stir up a hornets nest...

If a Speer Gold Dot 125 grain round uses xx.x grains of Brand x powder... why would a Hornady 125 grain round use anything different? I have been told by people that have been reloading for years that it's all about the weight in the final analysis.

[MGySgt]

I have manuals... but I do not care for the way the powder companies seem to be tied at the hip with a particular round. Alliant only quotes Speer at least as far as I have seen and Hodgdon will quote Hornady.
You quote powder manufactures reloading books – not bullet manufactures manuals. I just checked my Hornady manual for the 125 gr XTP and it list powder charges from:
Accurate
IMR
Alliant
Winchester
Hodgen

[MGySgt]

. I never load to max specs....
How do you know they are not max or too light if you are not following established load data?

[MGySgt]

Now this brings up another question that will stir up a hornets nest...

If a Speer Gold Dot 125 grain round uses xx.x grains of Brand x powder... why would a Hornady 125 grain round use anything different? I have been told by people that have been reloading for years that it's all about the weight in the final analysis.

Well – they are partially correct. It also depends on the depth that the base of the bullet (or boolit) is seated to.
An extreme variance – 150 grain .38’s in either 38 Special or .357 Mag.
One is a 148 grain double ended wadcutter
The other one is 150 grain semi wadcutter
Do they both get the same powder charge of say bullseye or 231, or what ever? Your theory states they do.

I don’t have the bullets in front of me, but as a wild guess –
The 125 grain Gold Dot and the 125 Grain XTP do not seat to the same depth. (cannelur at different locations thus changing the size of the combustion chamber. The larger the case the less this will affect the pressure (percent of space reduced is larger in a smaller cartridge).
In the case of your Gold Dot and XTP – It may NOT make too much of a difference – however it could.

Hence start at the starting load and work up.