[TommyMechanic]

Hello,

Finally got my hands on a HK UMP 9mm bolt. I already have a USC converted .45 UMP. Should I...

1. Share host receiver? Is it really a hassle to swap the barrel?
2. Buy another USC & convert? Seems like USC's can be had for a pretty good price these days.

Thanks,


Tom

 

[Lohe]

Not a hastle to swap the barrel. You're supposed to buy a new pin for it every time you do but who knows how quickly they actually go out of spec. Most probably that suggestion was based on the barrel being swapped out for a new one because the old one is shot and not to change calibers, who knows though.

Personally I'm going to have a case with everything I need to swap from .45 to .40 to 9mm and just have one receiver, but if you can afford multiple USCs you might just have one set up for .45 and one for 9mm, up to you obviously.

 

[USMC-F4]

For the price buy another USC and convert. But if you don't the barrel change is easy, just pick up an extra barrel pin if you are going to swap a lot. Get the mags once they hit the streets. There should be a bunch coming in soon... my 0.02 worth.
Cheers!

 

[hk94dude]

I say share the host. I converted my .45 to 9mm and kept the parts around in case I ever wanted to switch back to 45. A year or so later, I realized I never converted it back to .45, so I sold off all the parts except the bolt.

 

[DarkPhoenix]

I plan to do the same thing. And think that sharing the same receiver is the most economical way to go. I plan to pick up another firing pin assebly and spring to have one for each bolt.

 

[Gunschlinger]

I would have 2 USC's. Yeah it costs more but do you really want to play transformers at the range with one gun or do you want to have 2 dedicated guns ready to go?

 

[Schlafftablett]

As a general rule manufacturers recommend changing roll pins after each use because they take a set after initial insertion and don't usually hold as well the second and proceeding times. That said I re-use barrel roll pins in any USC conversions I do unless specifically asked not to and I've never had an issue.

 

[hk21man]

Reusing pin shouldnt be an issue.
While making all the different UMP 9mm barrels I did a lot of swapping and
banging the pin in and out. The ends are all beat up and mushroomed but still holds perfectly.
Thanks,Mike
MM

 

[kabob]

If you can afford it, go ahead and get the second USC and convert it. If you ever get bored of it or feel like one is enough, you can sell one of them for pretty much what it cost you. Also, barrel pins are only $9 on hkparts.net.

 

[GEBEBPRS]

We made a ball detent push pin for testing. No issues. I agree with GunSchlinger have 2 USC. It's easier at the range.

 

[TommyMechanic]

Looks like I will be in the market for another USC...

 

[rwa]

I have 2 ump's one in 45 and one 9mm. I thought about converting my 45 to a 9 but I just bought another usc and converted to 9mm who wants to switch barells and bolts just make two dedicated rifles to each caliber you will be happier in the long run

 

[snick97]

can i ask where u got the 9mm bolt? genuine HK, cool!

 

[veritas]

Looks like I will be in the market for another USC...

Have you had it milled for the USC? If yes, did you use HPDS and were you pleased? I need to send mine off. I reached out to Ed and have yet to get a response.

To your question: At $1250 or so its a no brainer, buy an additional USC.

 

[TommyMechanic]

can i ask where u got the 9mm bolt? genuine HK, cool!

Gbroker - HK UMP 9mm Complete Bolt Group *Brand New* : HK Parts at GunBroker.com

Have you had it milled for the USC? If yes, did you use HPDS and were you pleased? I need to send mine off. I reached out to Ed and have yet to get a response.

To your question: At $1250 or so its a no brainer, buy an additional USC.

I bought it already milled. Seller states it was done my HDPS - Looks real slick, no machine marks or anything.