Underwood 180gr 10mm

[mulyhuntr]

Bought 250 rds of this stuff to run through my new gen 4 G20. I put some rounds through my chrono and was kind of disappointed. Five shots averaged 1206 fps and underwood advertises 1300 fps.

Don't get me wrong, a 180gr bullet at 1200 is no slouch, but I was expecting a little more. I also shot some of my reloads with longshot and hodgdons midrange load of 9 grains surpassed the underwood by about 10fps and 9.3 of longshot surpassed it by over 25 fps.

All of the posts I read online make the underwood ammo in 10mm seem like some magic stuff. Definitely not knocking the ammo. It was accurate and functioned great. I think my expectations were just a little high with all the hype online.

Anyone else had similar results?

 

[Torian]

Factory recoil spring?

Underwood typically meets or exceeds fps ratings chrono'd out of my Elite Match.

 

[Thompsoncustom]

Hmmm ya I'd check the barrel length it's tested at vs what your is and if it's the ammo fault I'm sure the wonderful people at underwood will get you some more free.

 

[mulyhuntr]

Yes, it's the factory dual spring.