Can You load 9mm bullets in a .357 mag case?

40MM · March 2, 2007, 03:09 AM

The reason I ask is because I have a ton of 115gr 9mm bullets and I don't enjoy shooting my 9 anymore.( No challenge, too easy to hit the target!

) I understand a .357 mag to be .357 in diameter and a 9mm to be .355 in diameter. Will the slightly smaller size bulllet cause any problems? Thanks in advance!

rwilson452 · March 2, 2007, 05:54 AM

a single word answer is yes.

That .002 difference is just enough that it won't grab the lands properly if at all. turning your .357 into a smooth bore. It may not even seat in the case. If it doesn't seat and crimp you could have setback problems.

HSMITH · March 2, 2007, 07:28 AM

With some guns it works OK and some guns it doesn't work well at all. It just simply won't be great no matter what you do unless you put a .355" barrel on the gun.

Sizing the top 1/2 of the 357 case with a 9mm die is needed, otherwise the case won't hold the bullet. You also have to use a 9mm expander die.

It is worth a try, but don't expect much.

40MM · March 2, 2007, 07:37 AM

Thanks for the tip on using a 9mm die for the sizing, i was wondering about that. I will load some up tonight and test them in the morning! If Im still alive, i will report back!

40MM · March 3, 2007, 02:27 AM

Report back. So I loaded 5 rounds of 115gr conical lead 9mm bullets over a charge of 9.9gr of MP200 in a .357mag case. As expected, the muzzle flash was awesome! Very little recoil and good accuracy. (It was more me than the weapon that was responsible for the poor shot placement.) The distance was a modest 7 yards.After the third shot, the cylinder jammed up. I had to open the cylinder, pull the 3 empty cases out, then I fired the remaining two. The primers seemed fine, not flattened but the jamming of the cylinder makes me think something was not exactly right. During loading, there was no need to use a 9mm die, as the .357 die worked fine to seat and crimp the bullets. I use a Lee factory crimp die. The gun used was a Taurus 605 3" 5 shot. At least my curiosity is satisfied now!

March 2, 2007, 03:09 AM	#1
40MM Member Join Date: April 15, 2006 Posts: 69	Can You load 9mm bullets in a .357 mag case?(Report back) The reason I ask is because I have a ton of 115gr 9mm bullets and I don't enjoy shooting my 9 anymore.( No challenge, too easy to hit the target! ) I understand a .357 mag to be .357 in diameter and a 9mm to be .355 in diameter. Will the slightly smaller size bulllet cause any problems? Thanks in advance! Last edited by 40MM; March 3, 2007 at 02:32 AM.

March 2, 2007, 05:54 AM	#2
rwilson452 Senior Member Join Date: June 10, 2004 Location: Tioga co. PA Posts: 2,647	a single word answer is yes. That .002 difference is just enough that it won't grab the lands properly if at all. turning your .357 into a smooth bore. It may not even seat in the case. If it doesn't seat and crimp you could have setback problems.

March 2, 2007, 07:28 AM	#3
HSMITH Senior Member Join Date: June 21, 2002 Posts: 2,019	With some guns it works OK and some guns it doesn't work well at all. It just simply won't be great no matter what you do unless you put a .355" barrel on the gun. Sizing the top 1/2 of the 357 case with a 9mm die is needed, otherwise the case won't hold the bullet. You also have to use a 9mm expander die. It is worth a try, but don't expect much.

March 2, 2007, 07:37 AM	#4
40MM Member Join Date: April 15, 2006 Posts: 69	Thanks for the tip on using a 9mm die for the sizing, i was wondering about that. I will load some up tonight and test them in the morning! If Im still alive, i will report back!

March 3, 2007, 02:27 AM	#5
40MM Member Join Date: April 15, 2006 Posts: 69	Report back. So I loaded 5 rounds of 115gr conical lead 9mm bullets over a charge of 9.9gr of MP200 in a .357mag case. As expected, the muzzle flash was awesome! Very little recoil and good accuracy. (It was more me than the weapon that was responsible for the poor shot placement.) The distance was a modest 7 yards.After the third shot, the cylinder jammed up. I had to open the cylinder, pull the 3 empty cases out, then I fired the remaining two. The primers seemed fine, not flattened but the jamming of the cylinder makes me think something was not exactly right. During loading, there was no need to use a 9mm die, as the .357 die worked fine to seat and crimp the bullets. I use a Lee factory crimp die. The gun used was a Taurus 605 3" 5 shot. At least my curiosity is satisfied now!