45 super in a usp

[Rainbow Bullets]

I was reading the 40 super thread and read that you can shoot 45 super through an unmodified usp is this true anyone have experience? Should i get a new recoil spring and use a heavier spring if i do shoot it?
Very interested in 45 super looks fun but dont want to mess up my gun

[Beendare]

Yeah, those USP's swallow anything you put in them.

Personally, i only have one box of this through mine but it cycled flawlessly.

https://www.buffalobore.com/index.php?l=product_detail&p=78

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A guy over on pistol-forum has a long H&K thread detailing his experimentation with .45 super and if you own an H&K, its a good read.
He did have FTFs with the BB 255 gr hardcast

[cantdance]

I put a 6" barrel, 18# recoil spring and firing pin spring, +5% mag spring in my fs USP for 450smc. It's the same thing as a 45 Super with a magnum small rifle primer. HK states in the manual +p+45acp is ok, in stock setup. I wanted to give it a little edge. Double Tap Ammo has 450smc.

I haven't tried it yet in the HK but I have in a modified Colt 1991 with 10mm grade springs. I could not tell the difference in recoil from standard 45acp+p.

[Rainbow Bullets]

Good info beendare ill look for that thread.

Cantdance where did you get the 6 inch barrel im gonna be using a usp expert (5 inch barrel) it has a fully supported chamber and a dualsrping recoil system so do you think id be fine just putting in a 20lb or 18lb spring?

[Cato]

That's interesting. I've never heard this. What's the recoil like? My wrists hurt just thinking about it.

[cantdance]

Good info beendare ill look for that thread.

Cantdance where did you get the 6 inch barrel im gonna be using a usp expert (5 inch barrel) it has a fully supported chamber and a dualsrping recoil system so do you think id be fine just putting in a 20lb or 18lb spring?

HKparts.net. Was kinda pricy like $329 IIRC. The O-ring grove is cut for the full size USP, not the Elite or the Expert obviously. It will be ok for your Expert though. When I first found it they were out of stock so I put in for an email notification when it would be back in and forgot about it, thinking they'll probably never make them again. I forgot how long it took, it was a pretty long time before the notification came in and I jumped on it. You need to consider how much of a gain you'll get going from 5" to 6.02"

An alternative would be the Elite spare which is over $500 and I think those are always in stock. I wonder why.

As for the recoil spring I just arbitrarily choose the 18#. Wolff has them. Double Tap response to my Q, "Put in the 20 lb and go shooting!" The stock spring in the fs is 14# and I thought it too light for the 450smc/super.

edit:Removing and re-installing the little recoil spring retainer clip can be a real bougger. I managed while it was in the gun with the slide locked back and using a pair of needle-nose pliers and a small flat screwdriver. Persistence paid off.

[Rainbow Bullets]

HKparts.net. Was kinda pricy like $329 IIRC. The O-ring grove is cut for the full size USP, not the Elite or the Expert obviously. It will be ok for your Expert though. When I first found it they were out of stock so I put in for an email notification when it would be back in and forgot about it, thinking they'll probably never make them again. I forgot how long it took, it was a pretty long time before the notification came in and I jumped on it. You need to consider how much of a gain you'll get going from 5" to 6.02"

An alternative would be the Elite spare which is over $500 and I think those are always in stock. I wonder why.

As for the recoil spring I just arbitrarily choose the 18#. Wolff has them. Double Tap response to my Q, "Put in the 20 lb and go shooting!" The stock spring in the fs is 14# and I thought it too light for the 450smc/super.

edit:Removing and re-installing the little recoil spring retainer clip can be a real bougger. I managed while it was in the gun with the slide locked back and using a pair of needle-nose pliers and a small flat screwdriver. Persistence paid off.

Thanks again for the great info i saw the elite barrel as well if i can confirm it works on mine i may pick one up but you do raise an excellent point and the velocity gain does not seem worth $500 plus shipping and possible fitting
i did however order a new recoil assembly and new springs all around so i can just switch them out thanks for the tip on changing the springs i hope to keep spring changes to a minimum with thenew recoil spring assembly.
Have you tried underwood ammo i buy their 10mm ammo and its great im going to try the 45 super as soon as i get the usp situated (havent even gotten it yet waiting for it to arrive at ffl) Anyway thanks you have really got me wanting to try this!

[Beendare]

That's interesting. I've never heard this. What's the recoil like? My wrists hurt just thinking about it.

You can feel the difference. Those USP's have a pretty soft recoil though...so a little more is no big deal. Its nothing like the recoil in my SW.44 revolver...or even worse that SW 329PD..that thing is a beast.

The recoil feels like those 10mm Glocks- if you have ever shot one of those.

[cantdance]

Thanks again for the great info i saw the elite barrel as well if i can confirm it works on mine i may pick one up but you do raise an excellent point and the velocity gain does not seem worth $500 plus shipping and possible fitting
i did however order a new recoil assembly and new springs all around so i can just switch them out thanks for the tip on changing the springs i hope to keep spring changes to a minimum with thenew recoil spring assembly.
Have you tried underwood ammo i buy their 10mm ammo and its great im going to try the 45 super as soon as i get the usp situated (havent even gotten it yet waiting for it to arrive at ffl) Anyway thanks you have really got me wanting to try this!

I do know the FS and Elite are identical except for the length of course. I would think the Expert is no exception. My 6" dropped in no prob.

I think standard FS springs throughout are a good idea, esp the hammer spring. The target setups are a little weaker. I have a spare recoil assembly to swap out too. I vowed never to go through that spring switch ever again.

Never tried Underwood in anything. I'm happy with the Double Tap in 10mm and 45acp, +p, and 450smc. I like the Buffalo Bore 185gr 45+p Barnes too.