Why are you sorry?
Maybe I was tired.
FYI, a 50g 9mm doing 2400pfs claimed:
The problem with that round is it is a hollowpoint and the gel testing I have seen it had limited penetration.
Here’s another one of the ultra velocity 9mm options.
50 grains at 2000 fps, solid copper hollow point.
It looks to fragment the front half of the projectile and the base penetrated ~11" in clear gel.
Now it reads Velocity: 2040 FPS.
The problem with this ammo is it is a hollowpoint. At anything near 2000fps out of a 9mm if the projectile is a hollowpoint it will over expand and have very limited perpetration.
With the Leighi Defense it is designed not to expand and the flutes in the bullet due the work.
After I saw this I bought an aftermarket 357sig barrel for my M&P .40:
The 2nd shock wave reminds me of a mini depth charge
Here is a test of various Civil Defense rounds.
My problem with these rounds is that the penetration is limited.
Just got a message from someone, they said I could take my 9mm CMMG reem the chamber to 357sig and replace the bolt with a 40S&W. They have done this and they say it works great.
I found where I can rent a reemer, I have sent a request to CMMG to get a quote on a 40S&W bolt.
Doesn’t CMMG nitride their barrels?
oops one more thing to check on
Wouldn’t just swapping bolts and reaming the chamber not address the higher pressure of the 357Sig? i.e. wouldn’t it require a little buffer weight and/or buffer spring tweaking?
Yeah that could complicate reaming, especially if you are renting a reaming tool.
I know am reaching out to various barrel makers to find a 9mm barrel that can be rechambered and then try to find a place to nitride it
I not a science person, but what causes the second expansion of the gel. with the flash and such? I have never seen that.
Nitride isn’t really necessary.
It would be good to get a .40 barrel and copy the feed cone and or radius into the chamber. It may be different than blowback barrels, and I know that it matters a lot on blowback AR barrels for reliable feeding.
Feel free to ask me any tech questions that come up, I used to make AR barrels.
I was reading up on some RDB stuff, came across a mention of getting a custom 9mm barrel made.
I’m not either: https://en.wikipedia.org/wiki/Hydrostatic_shock
Excerpt: what is known to hunters as hydraulic shock—a hydraulic transmission of energy which is believed to cause instant death of animals hit by high velocity bullets
You’re seeing some crazy shit due to the velocity.
I want to be clear I would NEVER use Critical Defense ammo in 357 sig, they just don’t give the penetration needed.
Second I would not use conventional hollow points in 357 sig, if that was all I could get my hands on I would go back to 9mm.
The only round in 357sig that makes sense to me is the Leighi Defense 65 grain from Underwood ammo.
I have ordered a 40S&W bolt from CMMG, and I have found a fellow 357sig follower that is a gun smith and when I get the bolt he will ream my chamber from 9mm to 357 sig.
I will then achieve what I wanted for a PDW and pistol combination.