Recommended loads for New Toy - 357 Maximum

[CDF]

Hello again everyone.

Well, I couldn't help myself and have a new toy on the way.
I've been a Dan Wesson fan since the mid 80's and sold my DW revolver years ago. I've missed that firearm and have been looking for a replacement for the last few years but haven't found one in the condition I wanted.
I finally ran into a 40V8S 357 Supermag in 99% condition with the box, paperwork, barrel tool, and the unused extra barrel for deal I couldn't pass up.
I've never been a big revolver fan but the Dan Wesson holds a special place in my heart- and the accuracy of my last DW was unbelievable.

So anyway, I've got brass on the way, purchased a die set, and picked up some 170 and 180gr. Sierra bullets. Thankfully the 357 Max uses small rifle primers so I have plenty on hand. Now I am also very happy that I chose the Redding T7 Turret for my reloading duties since I still had room for the dies.
I have gone through the 4 loading manuals I have and 2 have specific 357 Max. info.
I figure I will try the AA1680 and VV110/120 (if I can find it) since the Sierra manual uses the exact firearm that I have coming.

Just curious if anyone is loading 357 Max and what powders you have been using with good results. I won't be firing anything under 170gr bullets in the Max load- if I want to shoot a lighter bullet, I will run 357 mag loads instead. I have read that anything under 170gr will create some top strap cutting and forcing cone issues in the Max load and I wish to avoid that problem as much as possible.
Any suggestions would be appreciated as always.

 

[flashguy]

I have 2 .357 Maximum revolvers, a Ruger SRM Old Model and a Seville. As you may know, I am partial to loads that produce a large muzzle flash and I eventually found a load using 110-gr bullets and a LOT of H110 powder. There was obvious top strap cutting on the Ruger and I would imagine forcing cone erosion, too. The Seville is made of very top grade aircraft stainless steel and uses a slightly longer cylinder and there is no top strap cutting I can see. I would not recommend my load for your use, which is why I'm not specifying it here. I retired the SRM and use only the Seville now. (It has a 5 1/2" barrel, too--special ordered.) The Seville is a superb revolver--too bad they stopped making them in the 1980s.

Here is a pic of my best friend shooting the Seville:

.

flashguy

 

[CDF]

Thanks for the picture flashguy- looks like fun.

OK, I have a new question. This may be a stupid question but I simply don't know the answer- I feel it would be more stupid if I failed to ask.
The Dan Wesson showed up and I have everything I need to work up a few loads.

I have been attempting to cross reference info from different sources for the powders I am using with similar weight bullets. I realize there are other variables at work and using load data for the same weight bullet from different manufacturers is not a very wise way to go, but I wanted to insure that I wasn't loading abnormal amounts of powder for a similar load- looks OK so far.
I would just like to post what I have done so that any errors I may have made can be pointed out. This reminds me of the wedding day jitters a bit.
So.... I loaded 40 rds of ammo for the 357 Max.

20rds. IMR4227-18.8gr , Sierra 180gr FPJ #8370, Rem 7.5BR primers, 1.900" COL
20rds. H110-19.8gr, with the same bullet, primer, and COL

Here is what has me concerned- the loads above are directly from the latest Sierra manual and are less than .5gr over the minimum starting load. Everything, right down to the firearm that I shoot, was used for Sierra's testing EXCEPT 2 variables: Primers and COL.
My COL is longer (since my cases are 1.600") and I am crimped in the middle of the cannelure. Since max case length is 1.605", I am not too concerned here.
My concern is the primers. The Sierra manual calls for a Fed205M primer but I instead used Rem7.5 primers. I am under the impression that the 7.5 primer is actually closer to a magnum primer than the 205M. Is this going to cause a pressure increase of concerning proportions?
Does anybody see any danger signs with these loads?
I would rather pull the bullets and start over if my primer concern is justified, or if these loads are in any way questionable.
Since I am at the low end of the load specs, would I be OK to shoot these while watching for signs of overpressure? Due to being a new hand loader, I am very paranoid to any changes from manual specs.


Thanks.