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P30 .40 S&W to .357 Sig Conversion Question

3769 Views 19 Replies 12 Participants Last post by  ARCTICDETH
Anyone here have any experience with the .40 to .357 conversion barrel sold here:

VP40 .357 Conversion barrel

My main question is will the 357 rounds feed RELIABLY in the P30 .40 cal mags?

Did a lot of searching and found the answer as it relates to the USPc and P2000 models, but not this particular scenario. Thanks in advance for any experience you can share.
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I don't see why it would be any different. The magazines for the P30 are the same as the P2000/USPc except the body is longer to hold more rounds.
I bought my .357sig conversion barrel from HKParts. I paid a premium, but they had it in stock and the transaction was fast and smooth. Barrel drops right in and runs perfectly.
I just bought the P30LS in 9mm. Now a 40 cal P30 with this barrel is on the list....good news/bad news for my wallet.
I bought my .357sig conversion barrel from HKParts. I paid a premium, but they had it in stock and the transaction was fast and smooth. Barrel drops right in and runs perfectly.
And this is on a P30?
And this is on a P30?
It is on a p200sk. When I visited the link, I missed that the barrel offered is not an HK brand barrel so my experience with the product is not relevant. Sorry. However, my experience with HKParts is that they would not carry a product that is poor quality.
I haven't seen many comments about this .357 sig barrel for the P30, but I have seen a lot about the RCM barrels for the vp40 and all of those reviews were positive....let us know if you grab one and how it works out. I have been kicking around grabbing one for my P30.


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I haven't seen many comments about this .357 sig barrel for the P30, but I have seen a lot about the RCM barrels for the vp40 and all of those reviews were positive....let us know if you grab one and how it works out. I have been kicking around grabbing one for my P30.


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Kind of waiting to see if anyone has any firsthand experience before I blow $240+! The RCM barrels seem to have a good rep, just concerned with reliable feeding of the 357 in .40 cal mags. I know if the case of the full-sized USP's it's a no-go.
Kind of waiting to see if anyone has any firsthand experience before I blow $240+! The RCM barrels seem to have a good rep, just concerned with reliable feeding of the 357 in .40 cal mags. I know if the case of the full-sized USP's it's a no-go.
I hear ya there. Those that got the .357 sig barrel for the vp40 said they fed very reliably (same magazine....).

So here's the link.....someone mentions that the p30 with the .357 sig barrel had a bunch of issues.


http://www.hkpro.com/forum/hk-handg...ig-conversion-barrel-any-experiences-yet.html


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I haven't seen many comments about this .357 sig barrel for the P30, but I have seen a lot about the RCM barrels for the vp40 and all of those reviews were positive....let us know if you grab one and how it works out. I have been kicking around grabbing one for my P30.


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I have a P30 in 40S&W and would also like to know if a 357SIG exists and if it is reliable.
Same, what are the 357 conversion barrels that are worthy!!!?
.40s&w to 357mag barrel swap.?””



For a P30 HK.
IS THIS POSSIBLE, OR WOULD A 357sig conversion barrel work???

Is the hkP30 capable of 357sig?

Never did this conversion before, and would like to find a good barrel to convert to 357 only if I ts reliable.
This would be a range toy
….Is the hkP30 capable of 357sig?

Never did this conversion before, and would like to find a good barrel to convert to 357 only if I ts reliable.
This would be a range toy
Yes, it is. Rim Country Manufacturing (RCM) makes these drop-in barrels, but they're out of stock. I have a P30L conversion barrel, and it works very well.

https://rimcountrymfg.com/product/rcm-hk-style-p30-357-sig-conversion-barrel/

Also try Bar-Sto and EFK Dragon. They might be in stock there.
Yes, it is. Rim Country Manufacturing (RCM) makes these drop-in barrels, but they're out of stock. I have a P30L conversion barrel, and it works very well.

https://rimcountrymfg.com/product/rcm-hk-style-p30-357-sig-conversion-barrel/

Also try Bar-Sto and EFK Dragon. They might be in stock there.










Will investigate!
Thank you.
Always nice to have options.

I know the .40 is rough on slides and can cause kabooms.
Would the .357 be less prone to a malf?

This is my first time thinking,... about this kind of conversion.

I’m always nervous about ad ons, tweaking, swapping a barrel.
I’m one to keep stuff in the stock configuration, but this has peaked my interest.

If this is safe, and no chance of damage to a pistol, I may think about trying this for range fun.
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Will investigate!
Thank you.
Always nice to have options.

I know the .40 is rough on slides and can cause kabooms.
Would the .357 be less prone to a malf?

This is my first time thinking,... about this kind of conversion.

I’m always nervous about ad ons, tweaking, swapping a barrel.
I’m one to keep stuff in the stock configuration, but this has peaked my interest.

If this is safe, and no chance of damage to a pistol, I may think about trying this for range fun.

I would be very interested in why you make this statement. Experience? Internet lore?
The USP was designed by HK for the .40 S&W cartridge. With commercially manufactured ammunition, my .40’s have run for thousands of rounds with no issues. HK is not going to build a pistol prone to “kabooms”. It’s an irresponsible statement. Unless you have specific proof, please stop spreading inaccuracies.

Lastly, you will find .357 Sig to be pretty pricey for “range fun”. Not saying it won’t be fun, but the only part of me that was affected by the recoil of .357 Sig was my wallet.
Good luck.
357 sig is actually fairly cheap to reload. The most difficult part is crimping without crushing the shoulder of the cartridge and making it unchamberable. I use a Lee factory crimp die. It's virtually impossible the crush one with that die. Anyway, reloading was the solution to the expense of shooting 357 sig for me.
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Kind of waiting to see if anyone has any firsthand experience before I blow $240+! The RCM barrels seem to have a good rep, just concerned with reliable feeding of the 357 in .40 cal mags. I know if the case of the full-sized USP's it's a no-go.
The .357SIG is a bottle necked case and feeds great in my USPc .40 short and wicked magazine. This is on my P2000sk. I can't stress this enough, a bottle neck case will darn near always feed better. I have never seen a .40S&W magazine that wouldn't work with a .357SIG cartridge. If someone know of one that doesn't work, I'd like to know about it.
Will investigate!....I know the .40 is rough on slides and can cause kabooms. Would the .357 be less prone to a malf?

This is my first time thinking,... about this kind of conversion.

I’m always nervous about ad ons, tweaking, swapping a barrel.
I’m one to keep stuff in the stock configuration, but this has peaked my interest.

If this is safe, and no chance of damage to a pistol, I may think about trying this for range fun.
The P30 in 40 can handle the higher internal pressures of a 357sig cartridge. I've been running the 357sig in my P30L with no problems (now up to 3000+ rounds) with my RCM barrel. The Bar-Sto and EFK barrels should also serve you well. Just drop-in the 357 barrel and you're GTG. No changes to mags or gunsights are necessary.

For range ammo, I use SpeerLawman, Fiocchi, and American Eagle because the loads are not that harsh. The 357 has a much larger bang and muzzle flash for sure, but ironically, the felt recoil is lower than the 40 IMO. I do recall you were using the SpeerLawman 40 in 165 grain for your P30. That is a mean tough round for that gun. When you use the SpeerLawman 357 in your P30, the felt recoil will be much lower on your hands once you get past the loud noise and flash.

Enjoy!!
+1 Vincent.
SAAMI specs 9/40 at 35Kpsi with the 9/+P at 38.5Kpsi, 357 is 40Kpsi. What’s given here is that HK has the P30/VP-Series (minus the SK) in OEM 40.
Note there is no P30/VP in 357, and there may be a reason. While the 357 is only +4% above 9/+P pressures, the HK print on accelerated wear applies.
As for 40 problems... not so much KB’s, but the HK 40 cracked-frame I’ve read are on suppressed guns (on HK’s that were not released with a factory TB config and using std/9mm RSA).
The P30 in 40 can handle the higher internal pressures of a 357sig cartridge. I've been running the 357sig in my P30L with no problems (now up to 3000+ rounds) with my RCM barrel. The Bar-Sto and EFK barrels should also serve you well. Just drop-in the 357 barrel and you're GTG. No changes to mags or gunsights are necessary.

For range ammo, I use SpeerLawman, Fiocchi, and American Eagle because the loads are not that harsh. The 357 has a much larger bang and muzzle flash for sure, but ironically, the felt recoil is lower than the 40 IMO. I do recall you were using the SpeerLawman 40 in 165 grain for your P30. That is a mean tough round for that gun. When you use the SpeerLawman 357 in your P30, the felt recoil will be much lower on your hands once you get past the loud noise and flash.

Enjoy!!













Yup, May have made a small mistake in buying 1000k rds of the Speer 165 in .40
The price was good.
I’ll be checking into the 180 as so many have instructed me to since.

Nice to know, I’ll shop around for a nice .357 conversion barrel for the P30.

Thank you all.
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