Inner barrel dimensions

[Muzza]

Just bought a metal barrel & silencer kit for the H&K UMP 45. Being so this has made it possible to fit a longer inner barrel. the Factory one is around 200mm, i'm looking for 300mm but im not sure on the width?

Can anyone help with this. Some guy on youtube had a 6.01 tight bore but he had swapped out his plastic hop up unit for a ally G36 one... bit confused here. Any help welcome.

cheers

Muzza

View attachment 16150

 

[Josh95]

6.01 is good for short range accuracy. 6.03 is the most common barrel width for outdoor use. expensive barrels 6.05 barrels are best for longer range

 

[Muzza]

Cheers,

I'll go for the 6.03.

Muzza

 

[Josh95]

However this is all down to certain variables, but 6.03 is a good middle ground

 

[ImTriggerHappy]

Barrel diameter is based on the internal size. External diameter is the same on all barrels.

Try this one

http://eagle6.co.uk/shop/catalog/product/view/id/1340/s/laylax-prometheus-returner-6-05mm-bc-bright-barrel-300mm/