Not to fear my Good ElJay -
We here love a good
rousing arguement opinionated discussion. And some of us get bored and offer anything we can that may not have anything to do with the original topic. Like Yours Truly.
As long as any eyes which were gouged out are handed back , with a mumbled appology, we usually make up and slouch home.
Heavens' Crow and Coffin are being downright congenial today, I don;t even see any signs of spittle and venom or blood!
Regarding your original question, allow me to begin with the "short answer" and then progress to my typical "long-winded speechifying answer".
Short Answer:
I would offer my opinion that your load (which exceeds max for .38 spcl) is "too warm" for your open top.
Long Answer:
Here is some dope straight from the manufacturor,
I included .38 Long Colt as representative of loads suitable for an open-top, notice the much lower loads :
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http://www.adi-powders.com.au/handloaders/single_action_pistol.asp?Calibre=38+Long+ColtBullet Powder Bullet Diam. C.O.L Starting Loads Maximum Loads
Grs. Grs (fps) Pres Grs. (fps) Pressure
125 GR. LRN AS30N .358" 1.400" 2.0 631 - 2.5 765
150 GR. LRN AS30N .358" 1.390" 2.0 624 - 2.6 744 -
http://www.adi-powders.com.au/handloaders/single_action_pistol.asp?Calibre=38+SpecialBullet Powder Diam. C.O.L Starting Loads Maximum Loads
Grs. Grs (fps) Pres Grs. (fps) Pressure
135 GR. CAST LRNFP AS30N .358" 1.418" 2.6 767 11400 cup 3.3 910 16200 cup
158 GR. CAST LSWC Trail Boss .358" 1.475" 2.7 661 11400 psi 4.2 804 13700 psi
158 GR. CAST LSWC AS30N .358" 1.475" 2.8 812 12900 cup 3.1 871 15100 cup
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Note that your load exceeds the recommended max.
Since the recommended max load for .38 special is 3.1 gr with a 158 grain bullet, and
the .38 Long Colt load is a mere 2.6 gr, I would suggest going lower with your open top than your Model 10.
Heck, I would go so far as to recommend dropping the charge for your Model 10!
Now bear in mind I am a conservative sort, your milage may vary and blah blah blah...
but since no one is out to kill bears with a .38 I don't see much downside .
hope this helps
Crow, Coffin. Give back any bits you tore off each other (if any) and pray continue
yhs
prof marvel