Some of the specs:
- Both of them are CO2 powered
- Both of them shoot 4.5mm BB's
- Both of them have blowback action
- Both of them shoot around 400 FPS
- The H.P.P is styled after the Sig Sauer 266
- The H.P.P is mostly all metal construction
- The H.P.P has a 15 round magazine
- The SA177 is styled after the Glock
- The SA177 has a metal slide and composite frame
- The SA177 has a 19 round magazine
- The SA177 has fiber optic sights
Here is a quick summary of these airguns…
Both of these Umarex airguns are great value for the money and both shoot pretty hard and accurate for blowback styled BB guns. Both have long trigger pulls with the SA177 being a bit on the heavy side. Neither one has a very heavy blowback feel but there is enough blowback to make them responsive and fun to shoot.
The construction on both of these BB airguns is overall very good with the SA177 being more realistic in comparison to the H.P.P. The H.P.P tends to be a more comfortable gun to shoot because of its weighty feel in the hand and lighter trigger pull.
I highly recommend both of these air guns. If you're looking for realism then get the SA177, and if you want the better shooter of the two, get the H.P.P.
I will be doing a more thorough shooting review with videos for each one of these Umarex blowback CO2 BB guns in the near future so stay tuned!
Here is the YouTube Video of my Umarex H.P.P and SA177 Comparison/Review: