Cowboy Rifle Silhouette load question

[Sixgun]

I already posted this on the Marlin Lever Forum but am not getting any responses so I moved it here to get a little more traffic.

I shoot Cowboy Rifle Silhouette using a Rossi 92 in 357 mag with a RCBS 180gr sil cast bullet. My load is 10 gr of AA9 with a CCI Small Pistol Primer and the RCBS sail bullet which weighes 190 gar from my mold. I use a 38sap case for this load because OAL is to long using a 357 mag case when the crimp is in the cannelure. I get right at 1300fps with this load with no signs of pressure. According to my calculations, I get a .83 foot pounds per second at the 200 meter ram, which seems to be enough because it knocks them down every time I can hit them.

My buddy wants to try my load in his Marlin Cowboy in 38 Special, for the same purpose. I figure that his action is probably just as strong as the action on a regular 1894 Marlin and it should handle the load fine.

Any opinions on this? Let me know what you think!

Sixgun

[Mikey]

Sixgun - Don't do it.  Basically, what you have done is to create a 357 magnum pressure load in a 38 special case.  It doesn't matter if the 38 SPL CB rifle is the same action as the Marlin 357 or not, those loads will be higher pressure than the 38 specials he would normally shoot through that rifle and I advise against it for safety's sake.  HTH.  Mikey.

[w30wcf]

Sixgun,
Your 180 gr. load is 30% below the  maximum load for the .357 Magnum
as shown in the Accurate reloading book.  Seating the bullet deeper would increase pressures though.

Since the steel and action type is the same in both rifles, both would tke the same proof pressure so I don't see a problem whatsoever.  

However, your ammunition may not feed in his rifle because it may be too long.

SIncerely,
w30wcf