HK USP 10mm conversion?

[supermario]

Have any of you guys done the 40cal to 10mm conversion on a USP. Ive seen it done on Hkforum.

I know it requires barrel to be reamed out, custom mags and recoil spring. But does anybody know how safe it would be? I would think since the USP have that crazy recoil setup that it should handle 10mm no problem.

Any info you guys got other than buy a Glock or 1911.

Thanks

[Bill Steele]

Given the SAAMI maximum pressures are almost the same (35Kpsi for 40 and 37.5Kpsi for 10mm), there would not be anything unsafe about it. The 10 case is roughly .140" longer, so the reaming would be pretty minor.

The things that might pose a more serious challenge would be the magazines and the internal geometry of the feed ramp and magazine followers, etc.

You would probably want to up the spring rate, I think guys that run 45 Super (similar energy to 10mm) in their USP 45's typically use like 22lb recoil spring and that is about it mod wise.

The bore axis on the USP is probably closer to a 1911 than say a Glock 20, so felt recoil will likely be more like a 1911 than a G20. With my hottest 10mm loads, my 1911's are pretty sporty, my G20 never a big deal.

You seem pretty ready to be turned off by the "get a Glock 20 or 10mm 1911" suggestion, so I won't make it. But if it were me, I would not put forth the time and money for such a conversion when there are better alternatives commercially available, oops, sorry I guess I just did it...

If you decide to do it, please start a thread and keep us updated on your progress. Good luck.

[Bullitt01]

Yes, please keep us up dated on that project.

[supermario]

Thanks for all the input. I decided im going with the Glock Either the G20sf with 6" barrel or maybe even the G29 with 6" barrel.
The reason I wanted a converted USP was because of the decocker and I didnt want a 1911 or any other 10mm because of the weight, or I would go with the Smith 1076. Im going to use this as a sidearm for hunting backcountry. My only concern with Glock was that there was no safety and Im a lil concerned with keeping one cocked and locked when hiking up and down hills. Its really easy to fall and or get something snagged. I know there are holsters but Im just a worry bird.

Anyhow, I had found this aftermarket safety for Glocks a long time ago but didnt feel the need for my HD Glocks. But now that I wanna carry this hunting, I think it will give me exactly what I want for my Hunting sidearm.
Here is a link. Tell me what you think about the product, I know most people think putting a safety on a Glock is stupid, so call me stupid if you want but it would make me feel safer carrying the Glock cocked and locked with safety on while hunting.

http://cominolli.com/product_info.php?products_id=29

Remember this gun is only for hunting. If any of you guys have ever heard or had any negative issues regarding this safety please let me know.

Given the SAAMI maximum pressures are almost the same (35Kpsi for 40 and 37.5Kpsi for 10mm), there would not be anything unsafe about it. The 10 case is roughly .140" longer, so the reaming would be pretty minor.

The things that might pose a more serious challenge would be the magazines and the internal geometry of the feed ramp and magazine followers, etc.

You would probably want to up the spring rate, I think guys that run 45 Super (similar energy to 10mm) in their USP 45's typically use like 22lb recoil spring and that is about it mod wise.

The bore axis on the USP is probably closer to a 1911 than say a Glock 20, so felt recoil will likely be more like a 1911 than a G20. With my hottest 10mm loads, my 1911's are pretty sporty, my G20 never a big deal.

You seem pretty ready to be turned off by the "get a Glock 20 or 10mm 1911" suggestion, so I won't make it. But if it were me, I would not put forth the time and money for such a conversion when there are better alternatives commercially available, oops, sorry I guess I just did it...

If you decide to do it, please start a thread and keep us updated on your progress. Good luck.

[Bill Steele]

Let me start by saying opinions are like noses, everybody's got one, so take what I am saying as it is, just an opinion.

I think your concern regarding the safety of carrying a Glock with a round chambered is misplaced.

The first thing to consider is when you rack the slide and chamber a round, a Glock isn't "cocked and locked". The firing pin is engaged but its primary purposed is to pull the trigger bar back into reset. The final "cocking" of the firing pin is accomplished with the trigger pull.

The second thing to consider is the only concern I have ever heard regarding Glock's and ND's is related to reholster operations when the user has their finger inside the trigger guard and reholsters, thus pulling the trigger. The noton that someone that fails to take their finger out of the trigger guard before reholstering is somehow going to remember to flick the safety on prior is, well, kind of randomly far fetched in my mind.

Although the forum is kind of dead these days, there are a LOT of guys that use their 10mm for woods carry over on the 10mm forum, http://10mm-firearms.com/. You might pose this same question over there, I think you will get some good feedback on different rigs for woods/hunting carry.

Finally, while the 6" barrel will definitely give you maximum velocity, there are commercial cast loads using the stock G20 barrel that will put two holes through anything you might encounter in North America. A 200gr WFNGC going 1200fps is not going to have a penetration problem in any animate object.

Good luck and enjoy the 10mm, great cartridge.

[Tiberius]

This is the minority viewpoint here, but I like the add-on safety on a Glock, and I'd get the 20 with the safety. I think it works a bit like a 1911 safety - easy to click off on the draw - though it may be a bit smaller. (Or maybe so much smaller that it isn't easy after all.) I've heard that adding these doesn't invalidate the Glock warranty, which seems like tacit approval from Glock.

I do get the argument that one should never have a negligent discharge, but as I look around I see cars with bumpers, and seat belts, and air bags, and then the stories of Glock leg. To me, the safety adds a small margin of, uh, safety - but doesn't replace the big one between the ears.

If you do get, post up some pics and a report, please.

[ThighSlapper]

I would just change the recoil spring on a USP .45 to shoot .45 super. Hoter than 10mm

[Bill Steele]

I would just change the recoil spring on a USP .45 to shoot .45 super. Hoter than 10mm

I think his USP is a 40.

[supermario]

Actually I just drosd a USP9 fullsize but was thinking about getting a 45 if the conversion was simple and safe and not too costly.

[Bill Steele]

Actually I just drosd a USP9 fullsize but was thinking about getting a 45 if the conversion was simple and safe and not too costly.

I misunderstood your first post where you were asking about the 40 to 10mm conversion.

ThighSlapper makes a good point regarding running 45 Super from the 45 model. It is just a spring swap. If you are running Underwood/Buffalo Bore the 10mm will deliver more ME and penetration will also be deeper due to its sectional density advantage over the 45 slug, but when you look at the terminal ballistics of the 45 Super loads of a 255gr LFN bullet, it is plenty for anything in North America.

[TVM]

Just throwing this out there...10mm Mark 23 w/16 round magazine! That would be cool!

[supermario]

OK so i started to look up the 45super/10mm ammo available from underwood or Buffalo Bore. It seems every where ive read, its best to use hard cast bullet for Bear or large animal etc.

Well in California we need lead free ammo. So even If i bought that, and just so happen to need to use it. I will be in trouble for shooting lead ammo


So the lead free solid copper stuff seems to be hollowpoint, which from my readings, would not be great to penetrate bears right.
like this https://www.buffalobore.com/index.ph...duct_list&c=98


Then there is hard cast bullets like this but they have lead.

https://www.underwoodammo.com/45-super-255-grain-hard-cast-flat-nose/

https://www.buffalobore.com/index.php?l=product_detail&p=219

[supermario]

This looks like good stuff but it dont seem to have much energy. Isnt that what I need.

https://www.underwoodammo.com/45-super-200-grain-xtreme-penetrator-box-of-20/

And then there is this 10mm lead free that looks good in numbers but its only 140grain. Is that enough or does it need to be around 200+grains

https://www.underwoodammo.com/10mm-auto-140-grain-xtreme-penetrator-box-of-20/

[ThighSlapper]

Only thing id be worried about is beating up the frame, wearing out the chamber. I dont think I could afford to shoot that much super to do either though lol

[supermario]

Yeah im not gonna be shooting 10mm or 45super alot. Just for practice, test rounds and periodically practice. Im trying to get the perfect hunting sidearm in my eyes.