# Why 120 grain ammo in a J Frame Air Weight?



## roadkingjim (Apr 9, 2007)

Question about minimum grain ammo in a Smith PD340 357. They say no less than 120 grain on the barrel. Why? What is the reason? I haven't used ammo less than 120 but I have a box of 357 mag 110 grain and I'm afraid to use it. I carry ccw all the time within the guidelines of the law in my state and have been using 38 +P 
I understand higher grain ammo = stopping power but will the 110 grain 357 damage the weapon? 
Thanks for the help.


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## TOF (Sep 7, 2006)

The superlights are simply not as strong as all steel and require a different set of limitations. IMHO


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## Bob Wright (May 10, 2006)

roadkingjim said:


> Question about minimum grain ammo in a Smith PD340 357. They say no less than 120 grain on the barrel. Why? What is the reason? I haven't used ammo less than 120 but I have a box of 357 mag 110 grain and I'm afraid to use it. I carry ccw all the time within the guidelines of the law in my state and have been using 38 +P
> I understand higher grain ammo = stopping power but will the 110 grain 357 damage the weapon?
> Thanks for the help.


Wow! You are taxing my memory. From my very hazy recollection, I seem to remember some problems with Remington's 95gr and 110gr. .38 Special loading from years back. Either the lead core separated from the bullet jacket, or the light bullets lacked momentum to clear the barrel, causing an obstruction in the bore. For some reason this was more pronounced in short, lightweight revolvers. And, I can't remember the publication, or maybe this was in the gun's owner manual.

This is about as vague as I get.

Bob Wright


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## roadkingjim (Apr 9, 2007)

That's makes some sense. I'm going to try to call Smith and see what they say. I'll keep you posted! Play on words!!:anim_lol:


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## roadkingjim (Apr 9, 2007)

I called S&W customer service and they told me the lighter grain bullet doesn't crimp as well in the case therefore it leaves the case to soon. The partially burned powder residue will damage the titanium.


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## Bob Wright (May 10, 2006)

roadkingjim said:


> I called S&W customer service and they told me the lighter grain bullet doesn't crimp as well in the case therefore it leaves the case to soon. The partially burned powder residue will damage the titanium.


Thanks for your response and follow-up. I did remember the problem but had forgotten the specifics.

Thanks again for refreshing my memory.

Bob Wright


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## abpt1 (Mar 4, 2007)

NOPE NOPE NOPE you guys are wrong :buttkick:....lol j/k

Its because the dam gun is so light that the bullet actualy will be pulled from the case making the cylinder stop rotating I have had this happen with 158 gr SWC hardcast hand loads ...because of a not strong enough crimp...I have shot 357 100gr powerball out of it with out faliure the factory crimp is good enough IMO I have shoot 100+ 100gr rounds with out a issue and carry that sam ammo ....


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